Furnace temp output

[Konrad]

What kind of warm air temperature output are you typically seeing at supply air vents, now that it's January?

[a46geo]

Konrad,

That answer may be as varying as the houses you inspect. The furnace temperature rise coupled with the return air temperature, type of duct work, distance from the heat source, the ambient temperature through which the duct work passes and blower speed would all affect the reading. Now add a modulating heat source modulating fan motors and different types of heat and I really don't think there is an answer for that question. The real test is; can the furnace maintain the thermostat setting?

Is there something more specific that you are trying to determine?

George

[Brian G]

I have no authority to base this on, but I look for at least 110 - 115 degrees down here, at the nearest register. I have read then as high as 142.6, and as low as 94.1 once. Heat pumps are a little worrisome to me; I'm not sure exactly what to expect from some of them.

Brian G.

Just My 2 Cents

[Terence McCann]

Hello Konrad:

On the older gas forced hot air units the fan/limit switch should be set for 150 degrees fan on and 100 degrees fan off / 200 degrees was the high limit setting. You can expect to see 125+ at the diffusers. Newer 90+ furnaces are somewhat lower (they also have new solid state time delays circuits for fan on/off operation not to mention 1/2 dozen high limits placed throughout the furnace).

Heat pumps, in this weather (0-10 degrees) will be running on electric strip heat. I would expect a delta T of 30 degrees +-.

[kurt]

Georges answer cuts to the heart of the matter; temperature is "important", but is somewhat meaningless if the equipment is not compatible w/ the house.