I need to purchase an external heat exchanger for a 5 panel/2 tank solar thermal heating system. The system is double pumped (of course) and both sides of the heat exchanger - the drainback side and the radiant heating side - are closed loops. (The DHW is heated from the radiant tanks, if the radiant tanks are warm enough.)
My city water, which will be used to fill the radiant heating side - is very hard, and will scale. But, it's a closed, 260 gallon (or so) system, and it will only scale until it's done scaling, I believe.
My question is this: I'd rather use a flat plate heat exchanger, if I can do so, without worrying about scaling because of the closed nature of the system. I'd rather not use a shell and tube heat exchanger.
Any thoughts on this choice?
Thanks in advance,
Jeff |