Solar heater

daveva

Well-known member
May 25, 2014
51
amsterdam ohio
Im planing on buying the heliocol system. I was planing on putting these panels in a wood box painted black inside covered with tempered glass. The reason for this is I was thinking I would increase the heat transfer to the panel and also it would winter better here in northern ohio. Any advice would be appreciated Thanks
 

gwegan

TFP Expert
Apr 19, 2013
2,769
Sacramento, CA
i hav e my doubts its going to make much of a difference. It may make them less effective as they will not have direct radiation to the panels. Additionally I have my doubts that the glass will cut down on the uv hitting the panels so they will age just as quickly.

Solar works because of the incremental increase in heat. Its not a heat the water up as much as you can system. Its an incremental replacement of the cooler water with warmer water.
 

Isaac-1

TFP Expert
LifeTime Supporter
May 10, 2010
6,711
SW Louisiana
I would not do this for several reasons, to put it simply heat transfer does not work the way people think it does. Commercial unglazed panels like heiocol sells is already well over 90% efficient at converting sunlight to heat under ideal conditions (no wind and daytime operating hours temperature within about 20 degrees F of the desired pool temperature). Putting the panels in a glazed box like you describe can in theory help IF the daytime air temperature is more than 20 degrees cooler than the desired swim temperature, in this case lets call that daytime air temperatures of below 65 degrees with a desired pool temperature of 85. The down side is you take a performance hit on the total amount of potential heat getting to the panels, common clear window glass is going to reflect about 11-15% of the light hitting it, plus it is going to absorb nearly all of the infra-red light and then reraditate half of that back out and half inside, so long story short. A glazed box will have about 50-70% of the heat gathering capacity of an unglazed panel, it will however benefit when temperatures are up to about 40 degrees different between the daytime air and the desired pool temperature. Of course this means the glazed array would need to be much larger than an unglazed to collect the same amount of heat, and at a 40 degree temperature difference the pool will be loosing much more heat, so the panels would need to be even bigger making such things impractical.


There is also the danger of melting the plastic panels in a glazed box in the heat of summer when there is no flow.

Ike

p.s. glazed solar boxes do have a place in domestic water heating where you are interested in peak temperature not maximum heat transfer
 

AUSpool

Bronze Supporter
LifeTime Supporter
TFP Guide
Sep 23, 2015
783
Brisbane, Australia.
Pool Size
5000
Surface
Plaster
Chlorine
Salt Water Generator
I installed a solar system in the begining of our summer, so glad I did. I looked at the Heliocol, Waterco, Oki, and glazed. In the end I went for the Waterco system. Waterco and Heliocol have a similar mounting system but Waterco use a traditional barrel type union to connect their panels where Heliocol uses a double C-clamp type system. I preferred the barrel union system and wouldn't have a hose and clamp system like the Oki uses.

Interestingly the Heliocol rep said they often instal without any mounting system even in cyclone regions, I wasn't happy with that. The Waterco instructions were a bit vague for a self instal with regard to leaving enough space for expantion and after installing on a hot roof I had a risk of pulling the panels apart when the temps droped in winter.


There is also the danger of melting the plastic panels in a glazed box in the heat of summer when there is no flow.
Very true. Boiling water and melting plastic under certain conditions which will occure and the main reason I didn't go for a glazed system. The glazed system I looked at constantly monitored panel temps and would activated the pump to cool them if necessary. But what if you have a power failure or in my case a controlled power supply that only guaranties 18 hours per day supply.



 

AUSpool

Bronze Supporter
LifeTime Supporter
TFP Guide
Sep 23, 2015
783
Brisbane, Australia.
Pool Size
5000
Surface
Plaster
Chlorine
Salt Water Generator
Waterco is an Australian listed company but do have a US presence, Waterco Pool Spa

But is not so much about which brand but rather knowing the pros and cons of each brand. The mounting system from my Waterco is the same as the Heliocol. Both only mount top and bottom, I supplied the SS steal strap myself.
 

Isaac-1

TFP Expert
LifeTime Supporter
May 10, 2010
6,711
SW Louisiana
I did much the same with my install except I used Aquatherm's optional 2 inch aluminum header clamps on my Techno-Solis panels ( spec sheets claim header diameter on the Techno-Solis panels is about 1/20th inch smaller than the Aquatherms), Techno-Solis uses common conduit U mounts standard. I also used vinyl coated stainless steel strap instead of the standard woven nylon strap (I was concerned about UV breakdown of the nylon over time).