On Jan 4, 10:31*pm, JIMMIE wrote:
On Jan 4, 5:01*pm, RBM wrote:





On 1/4/2012 12:53 PM, JIMMIE wrote:

My son has a home that he added a solar water heater to a few years
ago. Works great , too great. The unit far exceeds his demand for hot
water. He wants to add some coils to his forced air HVAC system so he
can use the solar heated water to heat his home. He was expecting
there to be a coil he could place in his HVAC system but cant find
what he is looking for or knows what to ask/google for. Any help would
be greatly appreciated.

We call that a "Hydro-Air" system. The hot water coils are inside the
air handler along with the cooling coils. I think he could make his
solar system assist the boiler, but I don't think I'd rube the air
handler to do it. Possibly if he T'd the solar loop into the boiler loop
where the go into the air handler, and set up some solenoid valves, so
whenever the thermostat called for heat, an aquastat on the solar system
would open it's solenoids as long as the water temperature was hot
enough. It would also have to turn on a circulating pump for the solar
loop. When the temperature isn't hot enough, the aquastat would close a
circuit, opening the solenoids from the boiler loop and it's pump, and
fire the boiler.
The problem with doing something like this, is that the only guy who
will know how to service it, is the one who built it. If anything
malfunctions, he could be without heat for a while

My son is an engineer who has a lot of "farm boy horse sense" and
pretty good about figuring out anything. He has already considered
that adding another coil may restrict the air flow too much. Not
knowing *any info on the heat exchanger it wasnt an idea he had
completely tossed. This system wouldnt be the only source of heat just
an augmentation to *to decrease his power bill hopefully. I think he
would be happy if it just heats his "great room". It is beginning to
sound like this is going to be a separate system that just heats the
main part of the house.

Jimmie- Hide quoted text -

- Show quoted text -

There will not be as much heat available as you think. A tankful of
hot water is not that much heat. You nedd to do some sums before
starting this work. It is probably uneconomic.