zimpzampzormp wrote:
1995 Lennox Pulse 21 furnace. Ironically I did everything from welding
the heat exchanger to assembling it to installing it in my house. I am
not an HVAC tech or an engineer.
The other day I noticed my second problem. A couple of years ago the
blower motor failed. Had to replace it with an upgraded motor as the OEM
was unavailable at the factory. Very successful operation. I also
replaced the air flapper as the old one was caked with dirt.
Last week I noticed it was short cycling. The purge blower would run and
the for about 5 seconds it would try to fire. Then it would go silent,
then the purge blower would run. Then the cycle would repeat. Anyway, I
found that if I have the thermostat set at 75 deg instead of the 68 deg
I usually run it at, it fires and cycles just fine.
Weird.
Before I call a real tech, does anyone think the problem could lie in
the electronic thermostat?

Thanks.

Was anyone playing with the thermostat and changed the "heat
anticipator" setting? For that matter, is the t-stat mechanical or
electronic?