The furnace ignites quickly with a blue flame and burns for approximately 2 minutes.
Then the whole unit stops silent for about a second.
Then the fan finally comes on after all of this and blows somewhat hot air for approximately
3 minutes.

The entire cycle is 2 minutes of burners, then 3 minutes of fan, then off for about 5 minutes.

It does keep the house at the temp I set the thermostat at. But it seems very inefficient.

Thermostat is set to 60'


Thanks for any help

Chuck Norris

Hi Chuck Norris. It sounds like your furnace has the Judo Chop Syndrome. LOL

It could be
The heat anticipator in the thermostat which will cause the burner to short cycle.
It could be the fan limit control that has gone out of calibration.
Keeping a low temp of 60 degrees depending upon the size of the house and the BTU capability of the furnace could trigger a short cycle situation.

Question, If you raise the temperature to say 65, does the unit stay running longer?