Heat test

When is the temp. to hot to test the operation of the furnace for heat? I know below 65f for the A/C. Just wondering if the same goes for heat also.

Regards

Gary

You can run a gas furnace at any temp.

If it is hot in the house already, the furnace may cycle. This should not be construed as a problem. The heat exchanger is getting too hot and the limit switch is cutting out. It will come back on in a few so long as the fan is running.

Does anyone run the furnance, when the temps are high in the house, to check for heating function on the furnance?

Regards

Gary

Sure, just to be sure it fires.

If the temperature is high in the house, I run the cooling first. Then I’ll run the heating and then return to the cooling for the rest of the inspection.