Solar Domestic Hot Water Installation

The installation began on November 26, 2009. That's Thanksgiving morning.

The Rack pieces for the 20 Apricus evacuated tubes are laid out on the garage floor. Yes, there are recyclables in the distance.
 Rack pieces
 The rack assembly is almost complete. Oddly the mounting centers are 47 inches apart, not 48. The piece at the bottom is what the bottoms of the tubes will clip to. After a bit more head scratching it gets mounted to the rack. 
 Now the rack is mounted to the roof. Time to join friends for Thanksgiving Day dinner. 
 Just another view of the rack. My roof is at 30 degrees. This rack boost the angle of the tubes to around 45 degrees which is about the latitude of my home. This is the recommended angle for the collector.
 
 This shot is looking straight up beside the chimney at the pipe run from the basement to the attic. These were my first copper sweat (solder) joints on this project. It was a little odd working over my head in the cramped confines of the furnace room. Glad to have my goggles and a water hose was nearby. 
 This is the furnace room. Those first solder connections are in the upper right corner of the photo where that bright spot is. You can see the clip lamp but the pipes are washed out by the light. 
 The pipes come through the roof into the attic. From there they head down beside the chimney. 

Previously, I topped off my attic to 16 inches of insulation, R-49. All I had to stand on were those little 1x3 perches I tacked on between the truss members. It was pretty cramped.
 
 I sealed some little gaps with spray foam insulation.

This roof penetration is from the hot side of the collector. The temperature sensor wire follows the pipe down.
 
 Here is the 50 gallon SuperStor Contender tank. It was fun getting that from my Prius into the house and down into the basement by myself. 

The cold in and hot out 3/4" domestic water pipes have been connected to the top along with ball valves. The 1/2" pipe on the left will carry the hot glycol from the collector on the roof to the coil in the tank.
 
 Here is the circulator pump now assembled to the flanges with 4 ball valves to isolate, fill and drain the solar glycol loop. 
 It took a while along with a lot of head scratching and basement cleaning to get all the plumbing done just in time for the first real snow of the season. It is now December 6 and time to put the evacuated tubes on the roof. 
 The snow capped manifold is seen here mounted to the rack and wrapped in plastic to keep the snow out of the holes the tubes will go into.

My buried safety rope is visible at the bottom coming over the edge of the eve.
 
 A borrowed air compressor was used to test the solar loop for leaks. Aside from a threaded fitting on the temperature pressure gauge reducer that I missed sealing with Teflon tape, everything was good.

The circulator pump (red) can be seen mounted to the plywood beside the tank.

Next I tested the solar loop with water at 30psi. It worked. I drained it before it froze.
 
 This is the pump used to charge the solar glycol loop. I borrowed it from LARELLALakes Region Living Lightly Association. They are trying to do the same thing PAREI does. 

The pump was still in its box. I added the fittings and mounted it to a bucket to make it useful. It gets connected above the circulator pump with a washing machine hose to charge the system.
 
 Using the mechanical advantage of a climbing rope and a few carabiner rigged as a block and tackle, I hoisted a plywood platform up the ladder and onto the roof. Setting up this rig took quite a bit of head scratching to convince myself it would work and therefore quite a bit of time. 
 Then I flipped the platform and tied it to the bottom of the rack with 1" tubular webbing (more climbing gear).

Of course the day started with clearing the snow from the roof.
 
 Next, a half box of Apricus evacuated tubes (5) is hooked and hoisted up the ladder onto the roof. The rope isn't quite long enough so I start by standing on the roof and pulling till the box is half way up the ladder. Then I step down the ladder over the box. 
 The box of tubes gets placed on the platform at the base of the rack. 
 Here the copper heat pipe with heat conductive grease (white at top) extends form the first evacuated tube ready to be inserted into the manifold. This is way exciting! 
 The second tube is being inserted into the manifold. this may actually get done today. 
 While the tubes are in their box on the roof I put the rubber cups on the bottoms. This protects the little nipple of glass left from the manufacturing. It also provides a means to safely clip the tubes to the rack. 
 It only takes about 15 minutes to put the first 5 tube on the rack. It take another 40 minutes to get the next box of 5 onto the  roof and ready for installation. 
 Halfway done and it is dark. Oh, and let's not forget cold. The weather is taking a turn for the worse tonight so I have to get it done now. 
 All 20 are now installed!! My frozen breath hangs in the night air illuminated by the flash.

Now it is time to take all the rigging down and clean up.
 
 The hot glycol comes down on the right past the pressure/temperature gauge and the pressure relief valve and enters the tank coil.

The cooled glycol leaves the tank at the bottom of the coil. It passes the solar loop drain and goes up through the circulator pump.

The dark gray panel on the tank gives access to a 4500 watt electric heating element for back up water heating.
 
 The tank at the top is an expansion tank for the solar glycol loop. 
 The SunEarth controller is in the hall. It compares the temperature in the collector manifold on the roof with the temperature of the water at the bottom of the tank. If it is 15 degrees F warmer on the roof it turns on the circulator until the differential drops to 9 degrees (I think).

This photo was taken at night. The outside air temperature is 6. The tank temperature is 76. The collector temperature got up to at lease 100 today. The outside air only got up to 15. Brrr.
 

This is absolutely the worst time of the year (December 17) for solar here in New Hampshire. The days are very short, less than 9 hours from sunrise to sunset. The sun seems to barely get above the horizon. There are still some trees blocking the sun from my roof that need to be cut. The fact that the system can deliver any heat at all is just amazing.

This has been a mighty exciting and fun project. In another month it should start producing really hot water. We shall see.
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