View Single Post
Old 12-27-20, 02:28 AM   #25
osolemio
Hong Kong
 
Join Date: May 2010
Location: Hong Kong
Posts: 108
Thanks: 20
Thanked 17 Times in 13 Posts
Default

Quote:
Originally Posted by solarhotairpanels View Post
Stag temps can go over 180... keep an eye on it.
You may have to run 3/4 copper for a few feet coming off the collector then back to Pex
I didn't get to it yet. Well, I have started sourcing parts, but an ongoing pandemic has slowed things down a bit, to put it mildly. Also, starting a company in HK is a longwinded process. Just getting a business account (not even with a credit, just a savings account), takes months.

About the temperature, I am not using PEX or any other plastics in the primary circuit. I would only use PEX for underfloor heating and some heat storages, where I can control the temperature. All primary circuits are copper or brass mainly. Trying to stay away from iron and steel.

The drainback will be a closed system, understood as in - the air in the system will normally not vent. If it's an open system (the air can enter and exit), then the air (and then water) will have oxygen added to it. This is not good in the long run, with regard to corrosion and such. So it will all stay in tanks, some of them with partly air in them.
__________________
Space heating/cooling and water heating by solar, Annual Geo Solar, drainwater heat recovery, Solar PV (to grid), rainwater recovery and more ...
Installing all this in a house from 1980, Copenhagen, Denmark. Living in Hong Kong. Main goal: Developing "Diffuse Light Concentration" technology for solar thermal.
osolemio is offline   Reply With Quote