Air Temperature Need For Effective Solar Heat

[Xndman]

One last question, I assume I should run the water through the heater on low speed (not high).

Thanks!!

[mas985]

Actually, heat transfer is better at higher flow since less heat is lost to the air when the panels are cooler. However, for energy reasons, you may still want to operate at low speed. If the panels are not excessively hot, then this is still efficient.