On Fri, 6 Jan 2012 09:22:07 -0800 (PST), "
wrote:

On Jan 4, 11:53Â*am, 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.

Do a google under : Hot water heating coils for residential
ductwork . Bear in mind that the added resistance of the heating
coil in the supply duct may require a larger blower assembly to
deliver enough airflow . Unless he has a huge daily storage of solar
hot water...i wouldnt waste the time or the expense .


Putting a standard automotive radiator of say, 6 square feet area,
into a 1.5 square foot return duct would have only 1/4 the apparent
airflow restriction because of the plenum required to fit it in - and
it would reduce the velocity through the rad by a factor of 4.

Using a thicker, smaller, higher resistance heater core in parallel,
with it's own blower assist takes the airflow resistance question
completely out of the equation.