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SUNMAXX SOLAR HOT WATER SOLUTIONS PROGRAMMING SMARTMAXX CONTROLLERS Presented by: Todd Paternoster Date: 11/15/2010 Okay. I’d like to welcome everyone to our Solar Programming SmartMaxx Controllers Webinar. My name is Todd Paternoster Director of Training for SunMaxx Solar. I’m going to take the next thirty minutes and cover in as much detail as I can domestic hot water and SmartMaxx controller programming. I’m going to try and answer all your questions. Please feel free to as always send me a question in the chat box. I usually do my best to answer them right away. Before I get into it can anybody confirm for me that they can actually hear me? That would be a good start. All right, perfect. Let me begin by introducing our two basic controllers that we have for here the SmartMaxx-DHWBPlus and the SmartMaxx Economy Plus. Obviously the Economy plus is a much more complicated controller. It allows you to tie into heating systems quite easily and often it can replace some of the home heating system logic. Now the SmartMaxx-DHWBPlus which is what I’ll focus on today gives you many options for your solar system. With only two relays and as you’ll see there are many things that we can do with those two relays. We can run pumps and valves or two valves and two pumps. As well as monitor performance data and log that data we can also tie into second tank or heat dump loop and obviously the b bus data logging capabilities. Okay the DWHBPlus has a thermostatic function as well as differential function. I’ll go into more detail as far as what that means momentarily. It allows you to set certain programs to activate at pre-determined temperatures rather than pre-determined differentials. They do use the PT1000 temperature sensors. As you might be able to barely make out in this photograph there’s a black and grey sensor. Just to point out the black sensors are rated for 280 degrees Celsius. So the black sensors are always what you use in the solar collectors. The grey sensors are used for the tank. These are a good controller to use for drain back systems. There are a few important functionalities in terms of how effectively a drain back system can operate using one of these controllers. There are nine different systems that are selectable that we can pre-program settings and just choose which array is most suitable. I’ll go over those in a minute too. There are also energy metering and very simple settings that you can activate. That allows you to monitor performance without having any additional software or any other components. This will be able to monitor performance for you as along as you activate that function as with all resale controllers. Yeah, it sure does Don and I’ll discuss that momentarily. You can pre-program your controllers based on the parameters that I’m going to introduce to you in a moment. But you can also tell your controller to do anything that you need it to do. There’s software that you can purchase and it’s fairly high end. It’s in the neighborhood of $800 for the software. But it’s a one time use and that will allow you to tell your controller to do things that’s outside of the standard factory setting options. So that is always an option for you. Now let’s just get right into wiring the controller first. Right out of the box you’re going to have a pre-wired controller. This photograph here you see the wires that the lead in the neutral and the green ground. They come pre-wired with our DWHB Plus pump station. Okay so if you order the controller separately you have to wire the circuit in. Very simple the lead in the neutral go to terminals 19 and 20 and the ground to 12. But if you buy the pump station with the SmartMaxx controller it comes pre-wired and all you have to do is plug the controller into the wall. The sensor wires on this photo I showed the brown on the left and the white on the right. However there’s no polarity to these sensors. So you can wire them which ever way you want. There’s no polarity on the sensor wires. If for some reason you don’t have the sensor wire wired properly there will be a flashing triangular sign on your controller. That indicates to you that the sensors are improperly wired. So it is relatively foolproof. The instruction manual is very detailed and laid out with troubleshooting guides in an attempt to make this what could be a complicated procedure and turn into something very simple. Often people will say “Do I need to hire an electrician?” Or “Should I get a certified or licensed electrician to do this?” And really the answer is up to the municipal code but in terms of what pre-knowledge it takes to wire these controllers is very basic. So my answer is “No, you don’t need an electrician in order to wire or program these controllers.” As you get into the economy system and tie into furnaces and boilers it does help to bring in an electrician or HVAC guy in. But this is something that you should be able to handle quite easily I believe. Okay now in terms of programming. You have only three buttons to choose from. They’re numbered one, two and three from the right to the left. My finger is on button number one. That button will forward the menu. So right now you see the photograph that says collector. That’s sensor is reading 71.9. It’s going to move forward to the next sensor. It’s going to move to all four sensors if they are installed. And then it will give you the Hp percentage the number of hours that the pump has run. Then the last option will be a time menu. Once you get to the time menu then you can begin to access the sub-menu by holding down button number one. So let me go to the next slide real quick and show you the different arrays. So these are the different options. This I took right out of the instruction manual just to remind you folks that you can go to www.sunmaxxsolar.com in the information section and download this controller instruction manual ahead of time. And often the manual will help you understand what type of system might work best for your application. So rather than working backwards building the system and deciding which array would work best. You may go the other way around and choose the array that best suits what you’re trying to do. Then build your system around that particular array and the functionality of the controller. So basically I have a standard solar system as array number one. Then you have a solar system with a heat exchanger. Array three is solar system with after heating. And then you have a solar system with tank charge where you’re trying to maintain stratification. We’re going to see more and more stratifying tanks and stratifying valves. They’ve been doing it for years in Europe and they really utilize and maximize tank stratification. I don’t believe the United States market has really tapped into this stratification performance yet. Now that’s a good question typically for array number seven it’s designed as an east west type of arrangement. I would recommend that you can use one pump with two valves because you don’t want to run…What you definitely need to have is two separate returns coming from the collectors. Because in the morning the east bank is obviously going to be hot. You don’t want the west bank to be circulating it all because it hasn’t picked up any heat whatsoever. So although this diagram here shows two separate pumps for the east and the west bank you could also just do one pump and one valve. It would be a little tricky for you to regulate the flow through each respective bank but it certainly is possible Joe. Then for eight the solar system with after heating by a solid fuel boiler. Number nine is solar system with heating circuit bringing the temperature from the solar tank and delivering it to the heating system. So basically array number nine is a mildly complicated copy system that you’re able to accomplish with only a basic controller. Those two relays can actually do quite a lot for you. What you won’t be able to do however is tie into the logic of your boiler with this particular controller. All right so basically what you want to do and let me remind you…Choose which array represents what you’re trying to do. I do recommend that you look at this instruction manual before you build your system and you can model your system after the functionality of the controller. Rather than trying to make the controller fit what system you have designed. Couple really basic settings before we get into it too much. You have the delta t o and the delta t f. You turn the pump on and your delta t o comes out of the factory set at 12 degrees. For northern climates we recommend you change the delta to o to 17 degrees. This gives your collectors a greater chance to heat up and really start to produce energy before your pump turns on. We’ve experienced a lot of short cycling the pump will turn on and then the fluid in the pipe will be enough to cool the collector off and then we’ll turn the pump off. Then we’ll turn the pump on and turn off and turn on and turn off. So by raising the delta t o up to 17 degrees particularly for northern climates then it reduces the short cycling of the pump. Now if your homeowner or service call for your own contract you can visit your systems twice a year. And if you did it in the spring and in the fall you would change the delta t o. Because in the summer time there’s no reason for your collectors to be seventeen degrees hotter before they turn on. So I recommend turning your delta t o down in the spring and then turning your delta t o back up in the fall. Particularly for northern climates but same is true for most of the places in the country. In the spring time you turn your delta t o down and then in the fall you turn your delta t o up. This is very simple to do and you can instruct your homeowner to do it or you can provide it as part of your service contract. The delta t f is what is going to turn the pump off. When the approach temperature or when the differential decreases and the factory setting is eight. We see in our systems we’ve turned that down as low as possible and five degrees seems to be a nice delta t f. So we recommend you change your settings down to five degrees. Okay anybody have any questions? Now in order to change those settings again there’s three buttons that you have to work with one, two and three. My finger is on button number one. Moving okay is button number two. And then button number three is the minus. I would like to point out that I do have a typo on button number three that’s actually button number one. On my screen you see array number one. Array number one that’s on the sub-menu. So you get to the sub-menu by pressing the plus button until it goes to the option called time. That’s the end of the main menu. Once you get to the end of the main menu you have to hold that button down for a few seconds. As you hold it down for a few seconds the sub-menu will appear. The sub-menu begins with your array options. So the first thing that’s going to appear in my sub-menu are the arrays. That would be array number one so I scroll through by pressing the plus button until I reach the array that is most suited for what I’m trying to do. Once I get to that array then I want to change that setting to array number two for example. So I hold the okay button down. By holding the okay button it’s going to cause the set. There’s a little icon in the screen with the word set. That set button is going to flash. As soon as that set button flashes then I can change the setting or I can push okay. If I push okay then it automatically changes to whatever appears on my screen. So I’ve gone to array number three and I like array number three. So I hold the okay button down for a few seconds. I get the word set to flash and then I press okay again one last time. I’ve automatically changed the setting to array number three. Now for each of the nine arrays factory settings will cause this controller to work. So all you have to do is change the array that you’re looking for and plug your controller in. The factory settings are pre-determined to make this controller function as recommended by the factory settings. So you really don’t have to do anything beyond choose the array. If you don’t even choose the array then the factory setting will be array number one which basically turns a single pump on. Now even though you’ve chosen the array. There’s still some functions within each array that you can activate. Many of the functions will not be active until you manually activate that function. Once you activate the function then you can change some of the parameters within that function. So I’m going to go through some of the functions here just a few technical things. This does have a built in transformer so you’ll bring a 110 volts in. This has two semi-conductor relays. So you will bring in 115 and you’ll send out 115. The display operates at 24 volts but like I said it’s got a built in transformer. So really this is fool proof. There’s no re-wiring or re-wiring of relays and switches. All you have to do is plug this controller into the wall and it will work. All right now let’s get into programming array number two. Here’s what I done is just showed you the two different arrays. Two of the nine and for instance every array has number one operates both relays. You have to enable certain functionalities. So I’m going to go through those functions now. For example there’s a table in your instruction manual that lays out the definitions of all these features. I’m going to go through some that I think are the most important and highlight why they are important. SMX is your maximum tank temperature. Now this does have a non-adjustable setting of 200 degrees. No matter what happens when your tank reaches 200 degrees Fahrenheit your entire system will shut down and it won’t be able to turn back on again until the tank drops below 200 degrees Fahrenheit. You can’t change this. You can however change your maximum tank temperature your preferred max tank temperature. We recommend that the tanks don’t exceed 180 degrees. So given a slight delay we recommend that you change your SMX function to 175 degrees. Now SMX has to be activated and you do that the same way that you choose an array. Once you’ve chosen an array then you continue through the menu until the three letters SMX appear. Once SMX appears on your screen and you hold the okay button down until you get the flashing set. Once you have the flashing set then you can adjust that temperature accordingly. And press the okay button and you’ve programmed it. So we recommend 175 for SMX. The emergency collector shut down now this is where you’re system will shut down when the collectors exceed the maximum temperature and it ranges from 170-390. We’ll 390 degrees is the stagnation temperature of the collectors. That is what they’re testing for at SRCC and Solar Key Market in Europe. Where there’s been no damage to the collectors and they’ve stagnated for thirty days at those temperatures. However right out of the factory or right out of the box these controllers are set for emergency shut down at 270 degrees. Now if you’re using type L copper or stainless steel you can handle 270 degrees. You’d certainly wouldn’t want your fluid to be circulating at 270 degrees. But if you have your pump on the return line going back to the collectors then you should be okay. So this is sort of a preference but you should not exceed what the factory setting is. You can’t turn it down but don’t turn the EM up. Again this EM is a function that you have to activate. OCC now this is going to cool your collectors down this is the heat dump loop or you have a secondary tank. OCC will be active once SMX is reached. SMX is the max tank temperature you set that at 175. Once your tank reaches 175 then OCC will be active. OCC will either trigger a second pump or it will open a normally closed valve. By opening the normally closed valve your solar pump will continue to pump even though you’ve exceeded SMX. So if OCC is not activated and you reach SMX then your solar pump will shut down. That’s okay as long as you have a second pump activated that’s going to act as your heat dump. But if you want your solar pump to continue to run even though SMX is reached then you’ve got to activate your OCC function. System cooling is another function so you have collector cooling but you also have system cooling. Now system cooling is where you want to cool your entire system down. Don, all systems don’t need a heat dump. Most often heat dumps are used in cases where you’re producing excess in the summer because you designed an economy system. Most often for hot water systems and as long as the storage tank has been designed properly. Then a separate heat dump loop is not required. There are ways such as steam back which I talked about last week. Steam back is going to allow your collectors to basically shut down their production in the case of over stagnation. So heat dumps are not always required although heat dump may not necessarily be wasteful. For example if you have a secondary tank the OCC function will activate that secondary loop. So rather than dumping into a heat dump loop you’ll dump into a secondary tank. Now system cooling function is when your entire system reaches maximum temperature but it’s less than emergency shut down. Now this OSYC function is something that you activate if you’d like your system to be able to bypass EM. In other words you’re going to exceed your maximum tank temperature that you’ve set but it’s still less than the emergency shut down then you can dump into a high temperature heat dump somewhere. I do not suggest you using OSYC with evacuated tubes. So that function is disabled the only way you can enable it is to activate it in the menu bar. For evacuated tube systems we recommend not using OSYC because the temperatures can spike so rapidly. Now the tank cooling function OSTC is a good way to cool your tank down during times of overproduction. So if you have a slightly over-sized system and you’re producing a little too much everyday for the month of August. Then you can dump some of those Btu’s out at night into your collectors by activating the OSTC function. This is something that you can activate seasonally if you like. It’s very simple. It literally will take you about five seconds to turn it on or turn it off. What’s going to happen if the OSTC function is enabled it’s going to automatically adjust your SMX. It’s going to bring your SMX down to whatever you set it at let’s say 150. So it’s going to cause your OCC loop to run once your tank is above the maximum set point. So by activating OSTC and setting that temperature that will automatically replace your SMX temperature. Which will cause the collectors loop to circulate at night time. Which means that you start the day with more of a buffer before you have to begin sort a safety mechanism. There’s another long term OSTC that you can activate and that’s called OHOL. This where you are going to be producing a significant amount of energy for an extended period of time with no load. In this case you’re going to everyday your solar loop will turn on while you’re gone and it will dump heat out until your collectors are the same temperature as your tank. So at night time what you want to do is deplete your tank of as much energy as possible because there’s no load. So essentially you’re creating a load on your storage tank using the OHOL function. Another important one especially in the north is the OCM. This is going to allow you to determine the temperature setting that you don’t want your pump to turn on until that temperature has been met. For example if you have a concrete floor and you’re operating your concrete floor at 65 degrees or 70 degrees. If you have a 17 degree differential your collector may kick on when it reaches 75 degrees. But at 75 degrees you’re not producing nearly as much energy as you might be consuming by running your pump. So it really isn’t paying to run your pump because you’re really not pulling any energy in your floor. So even though you’ve met your differential you activate OCM so that your collector loop will not turn on until you exceed 85 degrees or 90 degrees. Something that is a significant amount of energy that makes it worth your while to run your pump. Another very important one that I think is going to become more and more common. Replacing the antifreeze is the OCF function. Remember these are functions of the basic domestic hot water controller. So by replacing the antifreeze they glycol in your loop with this OCF function. What this is going to do is turn your collector loop on when the heat transfer fluid drops below a certain temperature. Now we recommend starting off at 35 degrees Fahrenheit this is going to be based off sensor number one which is in your collectors. Your collectors tend to cool off at a slower rate then you’re piping will cool off because they’re very well insulated. So what you should do if you’re going to use OCF is monitor it very closely because if for some reason you haven’t programmed it properly then you’re going to have some freezing in your line. So you’re really putting a lot of weight and a lot of importance on this proper operation of OCF. But if you can get it to work and give you accurate readings of temperature then it eliminates the need for any glycol in your loop and it also increases your heat transfer. And it increases your total system efficiency by eliminating that glycol. You do however sacrifice some of the energy that you’ve captured in order to keep your loop from freezing. So I’ve heard estimates and these are estimates only. But I’ve heard by using your OCF function in place of glycol you reduce your total Btu production by three to five percent. It consumes three to five percent of those Btu’s that you produced in order to keep your loop from freezing. But to me that seems like a pretty good trade off particularly because think about first thing in the morning when your collector loop might be 20 degrees and it’s slushy. Your collectors are heating up and now you’ve got to spend more energy to try to bring that entire loop up to temperature. So rather than spending the two hours of morning time sun just bringing your whole loop up to temperature. You could already start your loop at ten or twenty degrees hotter from using the energy that you captured yesterday. So I like the OCF function but I caution you to be very careful about accurate readings for your sensors. You should find the coldest spot in your collector loop. You can use sensor four which is just the data acquisition sensor. Use sensor four and place it where you think is the coldest spot and correlate sensor number four with actual readings of sensor number one. If those too…Yes, you can Don. Although it’s sort of redundant to use glycol and OCF it would be a good way to practice using your antifreeze function without the risk of freezing your loop. Okay couple of other important ones before I close it up here. OHQM is an energy metering function that doesn’t require the use of any other software or equipment. What you do need to have however and it’s included in the SmartMaxx. You need to know the flow rate in liters per minute. Open up this OHQM in your menu and press the okay button. Set button will blink. Once the set button blinks it’s going to ask for the flow. You have to enter the flow in liters per minute. And that’s the maximum flow. So you set your maximum flow and once you’ve pre-programmed your maximum flow for your system. Maximum flow is if your pump is running at a hundred percent speed what is your optimal flow rate. So once you program that it’s going to store your performance data on a daily basis. So at the end of each day you can go to your OHQM and look to see how many Btu’s have been produced by your system. It’s going to give it in kilowatt hours. But it can be easily converted to Btu’s. The manual shows the conversion chart. This is a good a way and most people don’t take advantage of OHQM. In fact most people don’t take advantage of most of the functions for this controller because they just aren’t familiar with it. But it can do a lot. OHQM is an important function especially for your clients’ ease of mind. To show them that your system is actually producing. It’s also a nice way for you to trouble shoot. Perhaps find places where you think you’re producing the energy but you’re not consuming it. So where do you have some losses. The drain back option this is going to do two things. Drain back option one will first start off your system siphoning by activating a secondary pump or ramping up the pump’s speed to a hundred percent until the siphon is achieved. That can take up to five minutes. So ODP has a time delay option that’s going send voltage to a secondary pump. That secondary pump is going to double your head which allows you to overcome that initial head from zero. Once you’ve created that siphon it might take up to five minutes then ODP will disable the secondary pump and allow the variable speed function to operate the circulator. It will also ramp up your existing circulator to a hundred percent or whatever is required to overcome the head. So you can get away with a larger more powerful pump just for system siphoning. Once that siphon is created based on the time sequence that you’re going to pre-program. It won’t be able to read whether there’s a siphon or not. But it’s going to be based on a time sequence that you’ve pre-programmed that you’ve observed how long it takes for this siphon to yield you. Then it will ramp it back down to the optimum flow rate. Obviously you have manual one for relay and manual two. This gives you the option of turning a relay on or turning a relay off or using the auto settings for your relays. So often times you want to override the factory settings for one time shot. So you go to man one and press your okay button and then it gives you the blinking set. There’s going to be three choices for man one. It’s going to say power on or power off or auto. So you can keep your relay off. You can keep your relay on. Or you can allow the automatic settings to override. So this is an important feature especially for starting the system up and trying to play around with it. You want to make sure that you get some circulation before you put your tubes in different things that you want to be able to change. Those are some of the most important features of the DHWBPlus that I wanted to go through with you. I did run over. I try to keep it at thirty minutes. I do have more that I’m going to just quickly introduce and move on. I’m going to do another webinar for the SmartMaxx Economy Plus. All the same functionality as the DHWBPlus however there’s many more things that we can discuss. The Economy Plus this is going to be another webinar we’re going to do in two weeks. Real quick some of the accessories that you can purchase with your SmartMaxx are the v bus. V Bus is going to allow you to integrate into a home computer system network system wireless. The data logger is basically an external hard drive that’s going to collect data for thirty days from your DHWBPlus or the Economy Plus. You can also get a touch screen monitoring system that can be monitored remotely. You can run some cables and bring it up to your homeowner’s kitchen if they want to see what’s going on. You can also download software for the IPhone and look at the entire system monitoring anywhere in the world. There’s also flow meters that can be installed for long term system monitoring system performance. As well as flow switch that will activate other relays not based on temperature or anything just based on there’s flow. Flow switches are used more often with domestic hot water systems and external heating exchangers. And anybody with an IPhone can download this app that allows you to see what your system is doing no matter where you are in the world. You log into a URL address that you have your v bus downloading all the information to. I know thirty minutes is not enough time to do nearly as much as I’d like to do with controllers. I do encourage you to ask questions. You can email me at [email protected]. Yes, Don both controllers will log the data with the Economy Plus and the DHWBPlus. So send me an email if you have any questions at [email protected]. Contact your sales rep for more information and go to sunmaxxsolar.com and download the DHWBPlus installation manual. Take a look at the arrays that are possible and start to think about designing systems and installing systems that the controllers are pre-programmed for. It’s going to make your job much easier and the performance is going to be better. So again there’s a lot more that we can talk about for controllers but I like to keep this at thirty minutes. I’ve already gone over for seven minutes. So please do email me and I’ll try my best to respond right away. Thanks a lot for taking the time to learn about the controllers and I hope to see you again next week. You can always go to solarwebinars.com and look at the archives for a review of any information that we’ve covered again. So thanks you all take care and we will see you next week.

SUNMAXX SOLAR HOT WATER SOLUTIONS MOUNTING STRATEGIES Presented by: Todd Paternoster Date: 11/22/2010 Well, welcome everyone. Good afternoon, welcome to the SunMaxx Solar webinar series. My name is Todd Paternoster. I’m going to spend the next half an hour talking about various mounting strategies and hopefully some of the information is relevant to what you’re trying to accomplish. As always the chat window is open and I encourage you to send some questions my way and I’ll try my best to answer them as they appear. So, without further ado some of you may be familiar with our webinar series. Each week we try to talk about something different and relative and updated. This particular week I’m going to talk about successful mounting strategies. Some of you may have seen a similar webinar a month or so ago and it’s similar, but with a few updates. Okay, so I’m going to get right into it. I’ve got a lot of different things to talk about in terms of mounting and every application is a little bit different. There are, you know, flat roofs, flush roof, tilt mount, ridge mount, steep slopes, shallow slopes can mount directly to the rafters on the rail systems. And neither option is better. It’s just everyone has a little bit different preferences. So, I’m going to try to present to you what SunMaxx has done to help make your job easier and give you the flexibility to install these collectors as you see fit. Okay. So, first of all let me talk for a moment about the new mounting hardware for the TitanPower Plus collector, our engineers have been hard at work and have come up with a very simple and obviously meets and exceeds code in terms of wind and strength requirements. And also, it’s extremely adaptable, very easy to install. I recently installed a system on my own home using the new mounting hardware for the TitanPower Plus and I was extremely happy with how easy it was to put together. Okay. Now, in terms of a single row of collectors versus two collectors or one collector, or multiple banks, the TitanPower Plus hardware gets assembled either a rail mount or without the rail and then the back legs mount directly to the roof. As you see in this picture, this is a photograph of the installation I did at my house. And I used the rail approach. I mounted the rails directly to the purlins off of some roof hooks, which I’ll show you in just a moment. Once the system was… Once the connect system was installed, the collectors simply sit on the rail system. And mounting the actual collectors took me and two of my friends only about 20 minutes to get all the collectors up on the roof and in place. So, once all the ground work is done in terms of mounting to the roof and setting the rails in place, putting the collectors is actually the easiest part, okay. It all starts with this roof hook and flashing. Whether you decide to go directly at point of penetration where you mount the feet directly to the roof or you use the rail, this is the first step. There are several different products out there that accomplish the same thing. Our roof hooks are adaptable for either point of penetration as in mounting the collectors directly to the roof or to the rail. The metal flashing clips sits underneath a shingle by about four inches, so, four inches of it needs to be underneath the row of shingles just above. And then we use these self threading screws to drill directly into the rafter. So, you’re not affixed to a particular rafter placement or position of your collectors, the roof hooks not to the rafters. Once you install a rail then you can slide the collectors to the left or to the right and make it symmetrical. So, these roof hooks have a very high sheer strength and they are aluminum. Now, once you install the flashing there’s absolutely no concern whatsoever for a roof leaking. In a system that I installed, I’ll go back one slide; you can tell I have a metal roof, okay. Well, what I did was use a small piece of butyl underneath the roof hook between the roof hook and the metal. And then I put a piece of butyl self adhesive butyl, on top of the roof hook. So I flashed on top of the metal and I am 100% confident for the life of this system that I will never have any roof leaks as bulk of my roofing skills, right. I know that using this roof hook with flashing will guarantee that there’s not going to be any leakage in my system. Okay. One of the next steps is the connection rail. Now, the rails are threaded to accept these Allen bolts. Okay, see the Allen bolt, those thread directly into the rail. So, once I install the rail anywhere along the roof hooks, and I have to space the roof hooks out four feet center on center. Okay, so I don’t want to put the roof hooks any more than four feet apart. The strength of the rail allows for displacement weight over four feet, but no more. Okay. So, the Allen bolts will thread directly into the rail as seen in the clip on the left. And on the right is the clip that attaches the collector to the rail. Okay, so the photo on the left is attaching the rail to the roof hook and the photo on the right is the clip that helps you attach the collector to the rail. Both of them use the self threaded Allen bolts that will thread directly into the rail, which makes it very easy and quick to install. Okay. It is a metric Allen and if memory serves me it’s nine millimeters. However, a small Allen wrench comes with your system. So, if you don’t have the Allen wrench you will have one included and shipped out to you in a little baggie. Okay. Now, in terms of creating back legs for these, there’s two pieces. Basically, one is the vertical support leg, which is made of the same rail or extrusion as the rail. So, some simple “L” brackets will connect the vertical rail to the horizontal rail and then the back leg. Now, in my case, I went with, what you see here is the hardware for a flat roof or a flat mounting install. In other words you’re either mounting them on the ground or in a flat roof. Okay, so I went with a flat roof, although my roof was not flat, I simply cut the back legs. Alright, so some simple trigonometry, which your sales rep can help you with or it’s also in our technical manual. Based on the roof pitch you will cut the back legs to achieve the desired angle, okay and then, obviously the “L” bracket on the bottom of the back leg will just slide up in the extrusion and mount directly to the rail. Okay, for long banks and collectors you have to union rails together. Okay, so there’s two rails that you’re going to use. One is the extrusion rail that mounts directly to the roof hooks, on the left. And those rail unions, along with their Allen bolts, will thread directly into the rail creating nice tight union between two rails, displacing the weight, hopefully. And on the right a “T” profile rail. Now, I’ll show you later on what a “T” profile does. That is basically the seat for the collectors. So, the “T” profile will mount to the rail and then the collectors will sit in the “T” profile and there’s small bolts that will thread into those slots that you see on the “T” profile gives at its strength. Here’s an up close picture of the “L” brackets that mount directly to the rail. Okay. So, what you’re seeing here is the vertical rail that the collectors lay onto. The “L” brackets then will mount directly to the horizontal rail that you’ve attached to the roof hook. Okay and this is all using the same Allen bolts. There’s a couple that are a different lengths, but they’re all labeled appropriately in your packaging. On the picture on the right you also see a clip. Now, that tension clip is going to accept the “T” profile. So, it makes it very adaptable by being able to adjust the back legs and front legs, to the left or to the right on the rail means they don’t necessarily need to measure exactly the length of my rail ‘cause I have flexibility laterally and as well as flexibility vertically in terms of distance because those little clips will slide up or down the rail, depending where you want your collector to be mounted. So, it makes it extremely versatile and adaptable, but also there’s a lot of wiggle room in terms of making exact penetrations into the roof. It’s not critical. There’s a lot of room for errors so to speak. We don’t particularly encourage error, but we do encourage efficiency. And this allows you to mount your collectors, err, mount your roof hooks in places where, you know, you’re going to get the tightest connection and then you have flexibility in terms of where your collectors mount relative to the roof hook. Alright, in this picture what you see is a TitanPower Plus flush mount. Now, you notice there’s two roof hooks on the bottom and two roof hooks on the top. So, that’s consistent with the recommendations that we make in terms of the number of roof hooks it is required per flat plate collector. Okay. Your sales rep will be sure to design your mounting system depending on what your considerations are. So, all that you need to know is will you put one or two collectors in series. And do you want flush mount or tilt mount? Once our sales rep has that information they’ll make sure that you have all the correct components included. Now, we do recommend that the roof hooks are placed in the middle of each adjoining collector. Okay, so whether you have two collectors or one collector it’s still going to require a total of four roof penetrations. So, four roof hooks, four flashings. Now, this is showing the tilt mount hardware. Okay, now the tilt mount would require three points of penetration as opposed to the flush mount. Flush mount tends to be less expensive because there are less components required. It’s also much easier to install. And I would like to make this recommendation now because it’s appropriate that if you have a roof that’s within 20 to 30 degrees pitch of what is the recommended, that the flat plate and the evacuated tube collectors will still perform within about five percent of their expected performance. So, when considering whether to do a flush mount as in this picture here, versus a tilt mount off the roof the to be added benefit to achieving that proper angle is really quite minimal. So, it’s important to consider obviously performance, but equally important, and in some cases even more important, it is to consider aesthetics, okay. So, I highly encourage you to consider flush mounting your collectors whenever possible. Flush mounting is going to be easier to install. It’s going to require less components and the performance sacrifices are going to be minimal. To be sure your sales rep will be happy to run a report at the various angles that you’re looking to make your installation. Okay, so again, if you have a roof pitch that is within 20 to 30 degrees of what the optimum pitch should be for your collectors you may consider just simply doing a flush mount rather than tilt mount, for three reasons, aesthetics, cost and installation time, which obviously, saves money as well. Okay, here’s another picture of the tilt mount using a rail system. Okay, now with the rail you accomplish obviously, weight disbursement, but more importantly you’re not fixed to rafter location relative to where your collectors are. And so, often, the back legs of collectors do not line up perfectly with the rafters. So, by using the rail system you can mount your roof hooks wherever your rafters are and then move your collectors laterally depending on where you’d like to see them sit on your roof, whether it’s aesthetics or performance, you have lateral movement on the rail whereas you would not have lateral movement with point of penetration mounting that is the back legs mounted directly to the roof. There are some exceptions to that, which I’ll cover in a minute, but generally you want to mount to the rafters. Okay, now here’s a tilt mount without using the rail. So, as I mentioned these points of penetration really should be at the location of the rafter. Okay, if you don’t find a rafter then we’re going to have to have access to these points of penetration underneath the roof. And we’re going to have to use toggle bolt or we’re going to have to use a spanner between the rafters, something that secures this entire collector bank to the roofing system rather than just the decking. This is even more important with flat plate collectors than with evacuated tubes, that you have your collector system mounted to the roof rather than mounted to the decking. And when I say roof, I’m talking about the structural components, that is the rafters or the trusses. Okay, so with flat plates you have a considerable amount of lift, a consistent and considerable amount of lift, on this roof system, especially if your collectors obviously, are facing to the south or in the southeast that means the back of your collectors would be facing to the southwest or the northwest where a lot of the prevailing winds come from. So, it’s important that you secure your collector system to the structural members of the roof and not just the decking. Okay, this is accomplished using a rail versus point of penetration. Okay, now in terms of roof penetrations, obviously you want to make sure that you don’t have to go back, and when you use a flashing materials such as the one shown here, this is PV quick mount that we used to use and I think it’s a very good product, you’re going to ensure that there is no roof leaking. When you do use these penetrations such as roof hook from SunMaxx or a quick mount PV, those ballasts, so to speak, should not exceed more than 48 inches apart. Okay, so if you have the wrong run, say of 10, 12, 20 feet or more, you’re going to have to use multiple rails. And I did show some connections that can be made to union the rails together to maintain a consistent strength. It’s also recommended that you pre-drill holes into your rafters, ¼ inch holes. In terms of rafter screws, we recommend that you use a three inch high sheer strength screw and that it be self threading, right, or that you pre-drill the hole. In terms of mounting these ballasts to purlins, for example, if the purlin is just an inch and a half material on its side then a three inch screw may not give you the support that you need. So, you know, you have that inch on the top of the screw where there’s no threads at all. So, you want to make sure that you know what you’re going to be screwing into and that the majority of your threads on the screw are holding the material that you are tying into. Okay, so if you do order the roof hooks from SunMaxx, you will get three inch screws, which is going to be suitable for rafter mounts, but if you did mount to purlins, for example, like I did, I had to replace my three inch screws, I went with shorter inch and ¾ screws to be sure my threads are mounted to my purlin. Now, there’s several different ways to mount to a roof. Five of which I mentioned here. This spanner method is where you have access to the rafters and below then you create a spanner between the rafters that you can mount your penetrations directly to the spanner. And this sort of serves the same purpose as mounting with a rail. It gives you horizontal flexibility to move back and forth and you’re not fixed to the location of your rafters. Another one is a lag bolt using flashing. Okay, the lag bolt, like I mentioned, should be at least three inches that’s going to all you to bolt directly to your rafters. Toggle bolts work. They are a little bit more cumbersome to work with and it works well if you have access to the roof below. The toggle bolt should be pretty big with a washer. Some guys are using a piece of plywood as a washer, so they’re using a four inch disk of plywood that acts as the washer for the toggle bolt and I do recommend that as well. “J” bolts have been used quite often in mounting to roofs. And basically, if you’re going to use a “J” bolt, you are fixed to the location of the rafter and you also need to have access to the rafter itself so that you know exactly where to drill and the “J” can then hook on to the bottom of the rafter. A pitch pan is one of the older methods that’s still being in use. Basically, you mount your lag bolt in through a pan that has a hole in the bottom that’s going to be filled with tar. So, it basically prevents any water penetration. Okay, mounting to rafters as you see here, the “J” bolt and the lag bolt detailed, “J” bolts are being used for, consistently for, but like I said, if you’re fixed to the location of the rafter, if you’re going to use a “J” bolt. As with the lag bolt, although with a lag bolt you can also mount in the case of metal loops, you can mount to the purlins if the purlins are made of a material that’s at least 2 x 4 inches. Okay. Using evacuated tubes, our hardware is universal, which is very important for those of you who are doing both tubes and flat plates. The hardware is interchangeable for either style collector. Okay, and as I mentioned, no matter what you should not exceed more than 48 inches between your standoffs. Okay, now flat plate flush mount, I think is probably the most aesthetically appealing system. Not to mention, as I said before, it’s the least expensive. It’s simplest to install, but in the end it looks very, very good. So, this roof being only at about a 35 degree slope would normally be situated at a 55 degree pitch for heating and I do remember running a report at 35 degrees versus 55 degrees and this client is sacrificing only about 7% of the total system outcome, total system output year round too, but mounting it flush rather than having it tilt mount. So, if you did a double bank of collectors, such as the one here with the tilt mount, there would be a fairly extensive system supporting those collectors off of the roof and gaining only about 7% total output. Okay, so it is a very important consideration to make and understand what losses you’re going to incur if you go the flush mount versus tilt mount. Here’s an example of mounting the “T” profile directly to the roof. And I’ll show you a photo in just a minute of how the “T” profiles mount to the collectors, but those little clips that you see there, those tension clips, can be mounted either to a hanger bolt as you see in that photo or the tension clips can be mounted directly to the rail. Okay, so all of our components, as I said, are interchangeable and adaptable for just about any roof style. Okay the “T” profile, when used with the hanger bolt, is going to mount directly to the “T” profile and then your “T” profile, as you can see here, mounts directly to the collector. You see the bolt being inserted through the slot of the “T” profile and that connects directly to the stainless steel frame of the collectors. So, there’s no other components required once the “T” profile is installed on the roof. It makes for a very simple installation especially for flush mounting. Okay, and this is what the final product looks like when you use a “T” profile connected directly to the collector and then the “T” profiles connected to the clip, which is connected to a hanger bolt, which is bolted directly into a rafter with a piece of flashing, okay. And that is a done deal, guaranteed not to leak for the life of the system. Now, there’s several different strategies I want to go over now just in terms of using your vacuum heat pipes and increasing your performance. Underneath the collectors with a highly reflective roof surface, you can boost performance of these collectors and I’ve seen actual performance numbers increase anywhere from 20 to 30 percent, depending on the type of reflective surface. So, when you’re installing the evacuated tube system, which I know that a lot of you are, it’s very important that you increase the reflectivity behind those collectors. Now, this is something you can suggest to the homeowner or that you can include as part of the system installation, but nevertheless you can guarantee that your system will perform better for the life of the system by increasing the reflectivity behind the vacuum heat pipes. And I would also point out that there’s a highly reflective roof coating that Sherwin Williams makes for $35.00 a gallon that can be painted directly on metal or asphalt shingles. So, I highly recommend looking at increased reflectivity. In terms of some different types of mounting there’s, you know, ridge mount as with the one that you see on the right. This client, his house was facing 90 degrees in the wrong direction, so he decided to do a ridge mount. I would caution you that making this system mounted perpendicular to the plane of the house does really destruct the aesthetic appeal, if that’s consideration. And the added benefit in terms of performance from 90 degrees off of ideal may only be in the neighborhood of 20 to 25 percent increase performance. Okay, so you have to consider, very carefully, before you mount to a ridge, is it worth it. And check with your SunMaxx rep. Ask them to do a report at the various azimuth angles and then you’ll know exactly what value you’re going to sacrifice by mounting it along the same slope as the house. Movable rays are not recommended, but they are possible. The reason they’re not recommended is because you have piping then instead of forming electrons you’re forming pressurized fluid, which tends to try to escape. And so the more often you move your array the more likely you’re going to have some leakage. And knowing that your sacrifices in performance are not nearly those sacrifices that you’ll see in PV systems, it’s not recommended that you design a movable system. Okay, now in terms of ground mounting, a lot of systems, a lot of guys who really like the ground mount because they’re easily accessible, they’re easy to clean, any maintenance problems and they’re also not subject to the particular angle of inclination and orientation of the house. They can be put off-site somewhere. We usually recommend that these systems not be installed more than 150 feet away from the house because once you exceed 150 feet you begin to experience a tremendous amount pressure drop, which means bigger pump and perhaps bigger piping and bigger piping is going to mean more losses. Okay, so a general rule about the ground mounting is that you not put these mounts more than 150 feet from the house. Now, ground mounts can be pretty difficult, but in cases where it’s the only option it is certainly not impossible to put a collector just about anywhere you want. In this particular system that was recently commissioned near Cooperstown, New York, the installer chose to use a cleared approach to the collectors. So rather than having them manifold to manifold to manifold, with brass unions, they are union together, but with flexible ConnectMaxx piping. Okay, so small sections are used to join one collector to the next. There’s a little bit more added cost for installation, obviously digging the holes and pouring the concrete, but the homeowner had a nice suitable location on a hillside, and you can pretty much guarantee that they are at the proper orientation and proper inclination. Okay, so ground mounting on flat ground and also underneath ground is very doable. It just needs to be well thought out. Mounting collectors on a flat roof is important to know that the evacuated tubes have very little wind load. And if you notice the picture here on the left these collectors are mounted just through these concrete blocks that are setting on the roof and in the picture on the right these evacuator tube collectors are used for shading for a carport. So, flat roof mounting is very easily done and often does not even have to penetrate the roof in order to accomplish that. Here’s another example of ridge mounting where the back legs of the collectors are straddling the ridge, still facing the same direction as the house. So, we’re not perpendicular to the ridge, but we are ridge mounting it by straddling the ridge. Okay, another flat roof install one important thing I’d like to point out in terms of flat roof install, particularly in the northern climates, is snow and we recommend that you bring your collector feet off of the roof by at least 12 inches in areas that are prone to snow loads. This will keep your collectors out of the snow, obviously. Allow for movement underneath the collectors, but it’ll act as a snow fence because often, if they’re connected directly to the roof, with no movement underneath, then you’re going to see the collectors work as sort of a snow fence. And there will be big piles of snow that trap behind the collectors. So, bring them up at least 12 inches. Here’s another example where the owner had used the white roofing to increase performance of the collectors. Pole mounts, in the case of, on the right hand side, this single pole mount is actually functioning as a pass through for the supply and return piping as well as the support structure for the collector itself. So, this install was able to get away with a single point of penetration using a steel pole to which he passed a supply and return. The one on the left with the core reflectors, this particular homeowner did not want his collectors on the roof at all. So, the installer was able to accommodate by doing a pole. Obviously, it’s going to raise the cost up considerably. Using concrete standoffs is also recommended particularly for evacuated tubes, ground mounts. This entire collector field is not mounted to the ground at all. They are simply bolted to these concrete standoffs that act as concrete shoes, for example. And the wind load being less than what the collector weighs, by adding these blocks and bringing them up off the ground, these are off the ground 18 inches as opposed to a foot. So, they’ve exceeded what we recommended, but they’re insuring that there will be no snow buildup on the bottom of the feet. In terms of reducing your summertime production, successful mounting can accomplish that, for example with the one on the left, you see the roof that the collectors are sitting on is acting as a shade for the bottom row reflectors in the summertime. So, he’s got four collectors total, only two of which are really operational in the summer, and then as the sun drops in the sky the bottom row becomes functional, or facade mounts, like these “U” pipes. Flat plates and evacuated tubes, if you do evacuated tube facade mount it’s got to be direct flow or a “U” type collector. Okay, flat plate collectors can be facade mounted and these are typically used for heating systems where you’re producing excess energy or more energy in the winter and then the production actually drops in the summertime with a perfect 90 degree slope. Overheating in situations where you have access to the collectors, they can be covered up, in a ground mounts not very accessible on the roof, but by having a steep angle, just like the facade mount you can also reduce your production. Drain back systems need to be mounted at ¼ inch tilt per foot whether it’s a sloped roof like the one you see on the right, or a flat roof as in on the left, all the manifolds need to be mounted at the ¼ inch of slope per foot. Now, ballast systems for collectors can be concrete like this or, pardon me, or they can be a wood ballast and if you do a concrete ballast then you use the hanger bolt. Those hanger bolts that you saw previously that spread directly into the rafter can also be put into concrete and then use the machine threaded to bolt the collector feet together. And then again, there’s your clip with your “T” profile and the collector mounts directly to the “T” profile. Now, here’s a couple of pictures showing the point of penetration with it over the shed. And then with the green roof this client chose to use the rail system. Okay, the considerations you have to make again are what type of wind load would your collectors be under. Okay, with evacuated tubes you can get away with mounting your collectors to the roof decking with some washers and big washers underneath. So, you’re basically connecting your collectors to the plywood that is then connected to the rafters. Not recommended for flat plates however, because of the wind load. The rail system just makes installation a little bit easier because you’re not fixed to the rafter location you can mount your rails and then mount your collectors and then slide them down as you see fit. Okay, a couple of important things I’d just like to bring up in terms of mounting strategy considerations. The ConnectMaxx hardware is universal. And so it’s universal in the sense that it mounts to flat plates as well as pitched roof, sloped roof, ridge mount, facade mount, cantilever, rail system versus not rail system. There’s virtually no roof that this ConnectMaxx hardware cannot be incorporated. And so it’s very important that you locate your sales rep and understand what you’re trying to accomplish and they will include the most appropriate ConnectMaxx hardware for whatever it is that you’re trying to accomplish. And it’s all put together with a single Allen wrench, which is included as well. Okay, now I’m going to end the meeting and offer my services to anybody that would have a question for me [email protected]. I’m more than happy to respond to anybody’s questions that you have. And I encourage you to join us again next week. Okay Dave, one second I’ll answer that, one moment. So, again, feel free to email me if you have any particular questions check our solarwebinars.com for archives of all the webinars. I think we’re up to, actually I don’t even know, 16, 17, 18 webinars at this point. So, we’re giving quite a lot of information to you guys as quickly as possible. If you have any suggestions for webinar topics that you’d like to see I am definitely interested in doing that as today I’m doing another schedule for the third quarter of 11, so please do take advantage of that. Send me emails with your questions and I’ll be happy to respond. Now, in terms of wind load, before we close, the wind load for flat plate collectors, the hardware is rated for 110 mph winds. Okay, so we have passed and rated our hardware at 110 mph winds. It’s apparently in testing right now for 160 mph winds. According to the mathematics that we’ve used it will pass the 160 mph test, but we don’t have that official stamp of approval yet. But, we do have a rating at 110 mph winds for both flat plate and evacuator tube. As you know evacuator tubes suffer from much less wind load than flat plates and require less material to connect to the roof. However, since our ConnectMaxx hardware is universal we’re using both flat plate and evacuated tubes for this hardware, they are, in the case of evacuated tubes, the hardware is probably well exceeds what’s required in order to hold it down in, you know, hurricane force winds. Okay, well there you have it. I’m going to officially end the webinar. Don, I went with flat plates on my house because of a radiant floor where I needed extremely low temperature heat load and it is also a question of aesthetes in terms of my house design. And so that’s a very good question and it’s not an easy answer. I went back and forth with flat plates versus evacuated tubes and it really just came down to what is most applicable for my particular application. Okay, thank you all take care and have a great Monday and I wish you the best of all available sunshine. Take care.

[iframe https://my.dimdim.com/view/reco/all/sunmaxx/default/ee08c153-a181-4823-900b-43734dba62f7 650 500] SUNMAXX SOLAR HOT WATER SOLUTIONS DRAINBACK SYSTEMS Presented by: Todd Paternoster Date: 10/18/2010 Good morning. Welcome to the next addition of our SunMaxx Solar hot water series webinar. Today I’d like to discuss drainback systems and how to optimize the performance for both flat plates and evacuated tubes. As always I welcome you to type any questions you have in the chat window. I can try to respond to those immediately. For those of you who are having trouble with audio just please refresh your screen. You might be able to eliminate any problems that you have. My name is Todd Paternoster and I’d like to spend the next half an hour talking about different drainback systems. I’d like to talk about the basics and we can get into some more complex topics. Although a half an hour is very short period of time to discuss too much. I’ll try my best to cover as much detail as I can in those next thirty minutes. So essentially drainbacks are a closed loop system. There’s different style drainback. You can do an open loop or direct and indirect. What I’m going to talk about today is a closed loop drainback that is indirect heat source. So we’re going to use a heat exchanger to dump into both heating system and hot water. Essentially drainbacks flood the collectors when the pump is on and when the pump is off for different reasons. When the pump is off the collectors will drain. Draining allows the fluid to leave the collectors preventing any overheating situation and also preventing any freezing situation. So drainbacks are relatively unique to the United States for them most part. In other parts of Europe and Asia most of the systems there are closed loop glycol systems. Drainbacks have been around for quite some time over thirty years. Particularly down in the Florida and the southern areas. But they’ve slowly made there way up north for heating systems. Particularly for systems that are sized for large heat loads in the wintertime and zero heat loads in the summer time. So drainback systems as you’ll see have several different merits. Obviously the first one is there’s’ no need for glycol. So as this picture depicts when the pump is off the collectors and the piping outside are drained. When the pump is on then the water in the loop displaces any of the air that is trapped in the collectors and in the tubing outside. Couple of the benefits of drainbacks it really in the function of anti-freeze. So from experience the only good thing about anti-freeze is that it doesn’t freeze. So with a system that doesn’t require anti-freeze. You don’t have all of the other drawbacks that anti-freeze is associated with more viscosity and heat transfer. Cost is another one. Drainback systems additionally have no need for an expansion tank. Presumably the volume of air that’s trapped inside the tank when the pump is on will suffice for any expansion that occurs during the heating up of the system. There’s also it’s an added safety for when the power fails or there’s a brown out or black out. The worst case scenario is the pump will shut off and if that happens then the system is protected if it’s designed properly. As opposed to a closed loop glycol system when the pump shuts off there have to be measures built into the system design that protect from overheating. Additionally there’s less annual maintenance. If they system is designed and installed properly there should essentially be no maintenance each year. Maintenance that would typically coincide with checking glycol acidity, maintaining system pressure and measuring the concentration of the glycol that can all be eliminated. Also there’s less oxidation of the system because presumably all of the oxygen will be used up during the system’s initial commissioning. In very short period of time the oxygen is consumed and what’s left behind would be the atmospheric nitrogen. So this will occur if the systems are installed properly and are tight. That way we don’t’ have any new oxygen gain or any pressure losses. A couple of drawbacks and the one that’s most apparent to me is that the collectors need to be mounted at a slope. So when you have a collector run of ten to twenty feet. What would be required is a drop in elevation from the high side of the collector to the low side of the collector of anywhere from four to eight inches. Now when mounted on a house that has straight lines the aesthetic appeal really drops. Here’s a perfect example although this collector system is probably working perfectly well dumping a lot of heat into the house. It is crooked and so as people drive by or notice the system on the roof that is crooked. They don’t’ realize the functionality of that slope so they might pass judgment. So you have to be very considerate of what the collector field will look like. In some cases aesthetic is paramount. Also if the system is not installed properly it can lead to lots of things that will go wrong for instance freezing pipes. All of the external piping needs to be mounted at a quarter inch to a foot of slope. With the drainback system it typically requires a larger pumps or secondary pump which I’ll show you in just a few moments. That secondary pump can be used to overcome the initial head that’s required from system start-up or when the pump initially kicks on. The second pump needs to be used to help overcome gravity. Once you create a siphon in the system gravity no longer plays a role. Another drawback is that there have been some complaints that drainback piping tends to be noisy. There can be some air entrained in the line that causes mini-explosions when high temperature meets low temperature. There can be some knocking in the pipe. So if you have piping that’s installed in the house. Clients will hear it when they first kick on their system until they get that nice siphoning going. So in most cases if it’s installed properly and out of sight. Then the first two drawbacks are irrelevant. Now with our newest controllers that offer variable speed function the third drawback can also be irrelevant. Because we can use a large pump to overcome that initial head and then the controller will throttle back the pump power. So that we’re consuming just what’s needed and nothing more. Obviously if you have pipes that are installed outside then the noise is also irrelevant. So there are many important benefits to drainbacks but it becomes more and more important that you consider some of the drawbacks before you make your final decision. Now let me get into a little bit of fundamental here. One of the benefits to drainbacks is it reduces the need for extra heat exchangers. Every time you go through a heat exchanger you undergo what’s called a performance penalty. Performance penalties can be removed from systems that are well designed. But regardless when you have a heat exchanger very rarely will you get a hundred percent heat exchange. For example this heat exchanger operating at fifty percent effectiveness. In other words the amount of energy that a heat exchanger can transfer across a heat exchanger is typically between fifty to eight percent effectiveness. So this means that if a collector is yielding a ninety four percent….They only yield ninety four percent of what they are expected to yield because of the fifty percent heat exchanger effectiveness. By looking at this graph there’s a diminishing return as you increase the performance penalties. So by eliminating this heat exchanger you essentially increase the system performance by six percent. So you have to be careful not to assume that just because the heat exchanger is operating at seventy five percent effectiveness. Doesn’t mean that you’re losing twenty five percent of the energy because it’ll just take more cycles to work through. However six percent losses can be pretty substantial. And why would you suffer six percent loss if you didn’t need to. So drainbacks eliminate that need to suffer from performance penalty because of this heat exchanger effectiveness versus quicker performance graph. Okay so here we have two drainbacks. We have an open loop and a closed loop drainback system. The open loop drainbacks which you see on the left are typically used with non-pressurized tanks. Non-pressure tanks are very popular with Combi Systems where you have a large reservoir of energy two, four, five, six hundred gallons storage tanks. These are very simple to design because being that the tank is not pressurized. All we’re going to do is pull fluid from the tank up to the collectors when the collectors are producing energy and dump back down into that non pressure tank. So we’re literally pulling the water from the tank to the collectors. Now it does require a system on the left like an open loop…It does require a separate exchanger because typically heating systems and certainly domestic hot water systems maintain an existing pressure. So we can’t introduce a pressurized system into a non-pressure system without the use of a heat exchanger. So although that system on the left the open loop drainback systems perform quite well and are very easy to tie into heating systems we do need to add a heat exchanger. The system on the right the closed loop drainback system where we’re maintaining a certain pressure. Now this system can be tied directly into heating systems. For example we can tie that storage tank being pressurized into pressurized floor, into pressurized baseboard or into a pressurized domestic hot water line. So first you decide whether you’re going to do pressurized or non-pressurized. One of the considerations of a non-pressure tank is the availability of large high volume storage tanks. For example if you designed a system that had a five hundred gallon storage tank. It becomes quite costly to have a five hundred gallon pressurized system. So non-pressure systems tend to be more cost effective when you’re talking about large Combi System designs. With closed loop they’re typically reserved for smaller systems they’re much easier to tie into because there’s no need for heat exchanger between the storage tank and the heating system. However there’s a limitation to the size of the pressurized vessel. I have seen three, four, five thousand gallon pressurized tanks but the cost is sometimes two to three fold that of the non-pressure tank of the same size. Okay here’s an example of a Combi System design that uses a pressurized tank and as you notice the fluid that’s passing through the collectors is the same fluid that’s delivered to the heating system. Whether it’s the heat dissipaters there…Whether the heat dissipaters are radiant floor or tubing or baseboard. It can also be forced hot air. The fluid from the collectors and the tank and the heating system are all the same. So there’s no performance penalty loss there. The only exchanger that you see in the middle of this tank is the domestic hot water exchanger. So when the tank calls for heat the boiler will add heat to the tank if the solar is not producing any energy. So the only time the boiler will dump heat into the storage tank is when the solar is not active. Now in this case the cold water comes into the bottom of the tank and works it way up and out through that coil. So the only heat exchanger is for domestic hot water. Typically heat exchangers on domestic hot water lines have a higher heat exchanger effectiveness or heat exchange capacity. Because of the larger delta t. The incoming cold water temperature versus tank temperature tends to be higher. Therefore we get a greater heat exchange rate and losses are much less. So the design that you see here is probably one of the best ones out there for domestic hot water heating system solar collector tie a pressurized drainback closed loop. You can also have a drainback system like this that does not use a heat exchanger. In this case the storage is the pressurized drainback tank in the case of the one before Don there is no storage for hot water per see. The storage is actually in the drainback tank so presumably we are getting a full recovery of cold water coming into the coil and leaving at the temperature of the tank. Okay. So we’re getting a large delta t from the cold water supply that comes in at fifty and leaves at a hundred and five or whatever you have it set for. At night our storage tank is going to be maintained by the boiler if the solar hasn’t been able to take care of it. So all day long the solar collectors bring the storage tank up to temperature. At the end of day if the storage tank is not up to temperature then the boiler will add heat to that storage tank maintaining that storage tank at a hundred fifteen or a hundred twenty all the time. Now with this one the difference is the drainback tank that is located outside of the storage tank. This small drainback tank only has to store the volume of fluid required to flood the collectors and the piping outside of the house. So in most cases this is a small ten or twenty drainback tank. By mounting it up towards the roof it eliminates the need for a larger pump or a second pump. Because you only have to overcome the vertical height that’s associated with the distance between the top of the water in the drainback tank and the top of the collectors. So the smaller that height the less pump powered required. Here’s a picture I have right out of Tom’s Lane lesson learned book of a drainback system that uses a pressurized drainback tank and a coil. Now this system is used mostly for domestic hot water system. The water in the storage tank is used for domestic purposes. Here is a diagram of a larger commercial pressurized drainback system that uses three tanks in parallel. Each of these tanks would ideally be the same temperature. And there is a larger drainback tank that will allow for any of the fluid in the collectors to drain into. Like I said before those separate drainback tanks can be anywhere from ten, twenty, forty and even eighty gallon drainback tanks outside of the normal storage. Now mounting flat plates to allow them for drainback as I mentioned it usually requires a slope of a quarter inch per foot. Now that slope can be apparent in the installation of the collectors or that slope can be taken care of in simply the piping. You only need stainless steel pumps for lines that are associated with domestic hot water or oxygenated loops. So for any system that’s a closed loop that has a pump cast iron will be sufficient. If the system is open that is with domestic hot water or a non-pressure tank then stainless steel or bronze pump should be used. In fact if it’s domestic hot water then stainless steel or bronze is code. So as I mentioned the flat plates don’t always have to be mounted crooked. But the piping will need to be mounted crooked. It depends what style. On the top you see the header riser style where we have all four panels are essentially piped in parallel. At the bottom we have serpentine. Now there are two different types of serpentine. This is a horizontal serpentine where the pipes are moving back and forth left and right. Horizontal serpentine collectors with a port on the top and a port on the bottom can in fact be used for drainbacks. However vertical serpentine where the manners go from top to bottom they can not be used in a drainback because it won’t drain. Typically flat plates have a header riser style internal piping. And most of those header riser style that have four ports can be used in drainback when they’re mounted properly. In terms of the mounting of the heat pipes there’s much less consideration it’s very straight forward. There’s a single pipe running through the manifold. That pipe like any other drain pipe needs to be mounted a quarter inch tilt per foot. Now that tilt can be accomplished in many ways by…For instance mounting it flush on the roof and rotating the entire piping at a quarter foot. Or mounting it on a flat roof like you see in this picture with one side proportionally higher than the other which allows for the drainage from left to right. But again when designing systems you have to consider what the aesthetics will be like. When you have a long run of forty or fifty feet. For example a four foot run will see just about an inch and a half of elevation change. So one flat plate will need to be tilted at about one point five inches. But for four flat plates now we’re up to six inches. So that slope becomes pretty noticeable as your runs become longer and longer. Now in order to overcome the initial vertical head we use a double pump system or a single pump that has a variable speed function. When you put two pumps in series you essentially double the head. Not double the flow but you double the head. That’s what the issue is with breaking gravity getting the flow from the drainback tank all the way to the collectors is like turning on a fountain pump. So it has to be able to overcome that vertical head. Now once the siphon is created so once we’re able to flow the fluid across the collectors and then fall back down. Then you count on the effect of gravity and that second pump can then go offline. Or a single larger pump would be throttled back. Now like I mentioned by taking the drainback reservoir and mounting it as high as possible you will loose some of the friction head because there’s a much shorter flow path. So if you have the opportunity to raise your drainback tank up to in an insulated space up to the point where just before it becomes non-insulated then you can dramatically reduce the amount of friction you have to overcome and take out the effected gravity. There are many questions about how to pressurize drainback systems. It’s got to have at least fifteen PSI in the system in order for the siphon to take effect. What’s going to happen if you start off with just fifteen pressure at the pump by the time you move to the top of the system the pressure will decrease. If it drops below atmospheric pressure then the boiling point is going to drop as well. It’s going to begin disassociate the… Yes, that is correct. So anytime you are introducing air into the system. You have to use stainless steel or bronze pumps. Now proper sizing for drainbacks in order to maintain a two foot per second of velocity in some cases a larger diameter pipe although it will reduce your friction will prevent siphoning from happening. So you have to be able to maintain a minimum velocity in your system. And velocity is going to be directly related to the volume and your pump speed. The volume is related to obviously to the diameter of the pipe that you choose. So for systems that require for example one point six gallons per minute we can go down to half inch type m copper or type l and that’s going to maintain two foot per second. If we need a gallon and a half a minute and we use three quarter inch copper then our velocity is going to be less than two feet per second. Which means you’re going to have a hard time maintaining that siphon. So the rule of thumb is you want to try to have the smallest diameter pipe possible while still maintaining a certain velocity. That minimum velocity is two per feet per second and the maximum velocity is five feet per second. So we want to try to maintain at least two feet per second in the lines and not to exceed five feet per second. So again by reducing the velocity you put more stress on the pump to maintain that siphon. So you have a better opportunity to create that siphon if your velocity is above two feet per second. You can use this chart to help guide what volume of piping I should use while maintaining two feet and not to exceed five feet per second. There’s many different options for drainback storage. There are ten, twenty, forty and eighty gallon tanks often they need to be mounted on top of an existing top. Or they can be mounted as I said in a larger space up in the attic. Some manufacturers have large eighty gallon tanks that eliminate the need for a separate tank all together. So most often is the case that the installers will choose a separate drainback storage tank that may or may not include a coil heat exchanger. Many times when a coiled heat exchanger is included in a drainback tank since it’s such a small volume. They increase the surface area by using thinned copper or dimpled copper to help increase the heat exchange capacity through a smaller coil. The UniMaxx drain back is ten gallon tank that uses a double pump. So we’re pumping through the collectors and a separate pump is going to re-circulate from the drainback tank into an existing tank with the use of a raised plate as opposed to an internal coil. There are many manufactures of stand alone units. We are just now bringing one to market that includes all of the components built in. Similar to a pump station but as you see on the left here it’s a pump station that stands up on it’s own with a separate drainback reservoir that re-circulates into an existing tank. A couple very important considerations before I close here. Is that all horizontal piping must be sloped and one of the challenges for many installers is to design a system that is both aesthetically appealing and can drain properly. So by looking at the lay out of the roof and the runs of the pipe. You have to be able to visualize every single horizontal of pipe needs to be sloped. In some cases it just doesn’t fit the aesthetics of the house so installers will choose to go with a closed loop glycol. Another important factor to remember is velocity must be two feet per second. Also often pumps come with check valves built in. I know Takeo and Burnfoss the standard pumps that might come with a pump station. Whether you get a pump station from SunMaxx or whom ever else often they have check valves built in. Now Takeo check valves are very easily removed with a pair of needle nose pliers. Never the less you need to be sure that your system does not have a check valve that’s going to prevent the fluid from draining back effectively. Many of the controllers now have a high limit shut off. Not only do they shut it off but they will keep it off. Now make sure your controller has this function enabled especially with evacuated tube drainback systems. Because as your pump shuts off because the tank reached a high temperature. If there’s a load on your storage tank causing the storage tank temperature to drop maintaining a delta t between the collectors and the tank. The pump is going to want to turn back on again. If this happens if your collector field is in excess of two hundred and fifty degrees you’re going to get some flash steam. Which isn’t necessarily a problem but it’s something you want to avoid having happen consistently every single day. It’s going to put undue stress on your piping and fitting and valves. So the controllers are designed now a days for drain back functionality where it will turn off the pump when the tank reaches maximum temperature. It will keep your pump off regardless of your tank temperature if the collectors exceed a temperature it’s typically set at about two hundred and thirty five degrees. Which in the case of evacuated tubes and flat plates as well…. When the pump shuts off in full sun those collector temperatures can climb up to two hundred thirty or two hundred forty degrees in a matter of minutes. So that’s a very important function to make sure is enabled. Also you need to maintain a minimum pressure inside the system to help enable that siphon. With lower pressure in the system you’re going to increase the siphon requirements. In other words you’re going to lower the vertical height that siphon can still occur at. So the more pressure in your system the higher the total vertical head can be while maintaining that siphon. And you don’t need an air vent. In fact you don’t want an air vent in the system. Obviously drain backs have no need for expanse state. Hi Pete. Just wrapping it up here. I am actually going to be done. I’ve gone two minutes over. If anyone has any questions I welcome you to bring them to me now. Otherwise I’d like to conclude and I hope to see you again perhaps next week. I’m glad Pete joined us maybe….Now would be a good time to bring it up Pete. To clarify the pressure I’m certain that you have something to say. But from my understanding the lower the pressure the lower the total vertical head that we can accomplish and still maintain a siphon. So I believe at one atmospheric pressure in the system we’re only going to be able to get about thirty to thirty five feet of head before the boiling point is so low. That we begin to break the siphon as the water moves over the top of the system. So by increasing that pressure it allows us to attain a higher vertical head and maintain that siphon. Okay. Well if anybody else has any questions I’d be happy to answer them now. And otherwise I wish you a happy solar day and hope to see you again. Take care. Bye.