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Old 04-26-12, 02:40 AM   #2
randen
Uber EcoRenovator
 
Join Date: Apr 2011
Location: Strathroy Ontario Canada
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Default Solar space heating in Canada

The installation of the solar collectors started with two purchased panels. (Solcan Canada)(Very Helpfull) They were installed vertically on the exterior wall between the patio doors. After reading about Garys solar shed (Builditsolar) and vertical collectors being a good thing for not collecting too much heat in the summer months and most heat during the winter months with the sun being lower angle, vertical mounted they were. (Thanks Gary Good advice)

The planned solar install was for 240 sqft of collector. I had decided to make my own panels to complete the install. It ended up taking me 3 years to get it all completed with all the other constuction going on. I did it in stages; 1st year 2 panels the results were on a really sunny day I could warm the floor about 2-3 Deg C. 2nd year added 4 more panels and WOW with the six panels we were able to heat the floor through 6 deg C. This would mean again on a really totally sunny day we would have enough heat to warm the concrete floor up and it would keep us warm till the next day to maybe get the next recharge of heat. This would be without any heat input from the GSHP. (FREE HEAT FROM THE SUN) Now the problem was not everyday is totally clear, some clouds do occure. There are some days with some thin high overcast that also reduces our solar gain. One other problem during the 2-3 weeks around summer solstice June 21 We were not always able to collect enough heat for the domestic hot water with the sun being directly overhead. The solution is for the last solar collectors to be able to be tilted. So far this tilted panel is performing exceptionally well. I'm seeing a difference of 10 deg.C. between the vertical and tilted panels.

In true eco-renovator style the panels that I had made were from some recycled materials. As mentioned in some other postings the risers were from the furnace oil supply lines straightened and soldered to copper fin purchased from the scrap yard. The tilting solar panels tempered glass is from the patio doors that had to be replaced. The stainless frame material is also from the scrap-yard.

The temperatures that are in the photos are average. The temps on the fluke multimeter of 53 deg. C.(photo wouldn't fit) are sometimes seen up to 66 deg. These are the glycol temps. from the panels. The temps on the Taylor are the domestic HW and usually finish the day 50+ deg. This would be 250 Ltr (60 gals.) of hot water till the next day. Lots for morning showers.The temps on the Rancor are for the floor heat and depending on the zones requiring heat. The supply temp can be anywere from 28 to 50 deg. (The set temp for the GSHP is 43 deg C) During the depth of winter a floor temp of 32 deg.C. is very nice and over night it may drop as low as 25 deg. C. but still comfortable. That would relate to an air temp 24 to 20 deg.C.

The controls are fairly simple with a differential controller. By about 10 O clock in the morning the pump may start. This signal also operates a timer/relay to open the circuit for the GSHP. This timer is set for 30 min. In the event that a cloud may roll by and the solar circulation pump stops momentarially we wouldn't like the GSHP to start. But 30mins after the sun is no longer producing enough heat the GSHP starts, if there is a requirement from the floor thermostats. But if we have recieved lots of solar heat the floor temps are above the set temps so no requirement for the GSHP to start.

For the last 3 weeks the GSHP has been switched off with the exception of 2-3 days (overcast) both domestic and space heat has been via solar. NICE. If anyone is thinking about solar heating it works. But the key things: The house needs to be very well insulated and air tight. 10-30 % solar collector per sqft. of floor space. For us, concrete floor for heat retention. Other source of heat for back-up is nessisary. DIY is possible with great results.

Randen





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Last edited by Daox; 01-10-16 at 03:19 PM..
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