Hi,

I bought a house with a standard natural gas furnace and a heat pump in the attic. The heat pump works great when I test it, but if I leave the switch on the thermostat set to EM HT (i.e. heat pump), once the heat kicks off it is replaced by a steady flow of cool air through the ducts/register. If I set the thermostat to HEAT (which is the furnace), there is no draft.

Any idea why the heat pump would cause a constant cool draft?

Any way to fix this draft problem?

Thank you

Well unless I`m mistaken, the them ht is emergancy heat which is your furnace,, when you set it to heat,(heatpump), backwards from your thinking ,so thinking you need to look into a fan control problem,or maybe tstat