Furnace Question

[zamboni]

Older dial style thermostat, heats set on auto at 70, wake up today and it is 60 in the house. Turn thermo up to 80, nothing. Turn it back down to 70, and click the switch from auto to ON. Kicks on. I am guessing it is time to upgrade to a digital thermostat, or at least a new one? Seems like furnace is working fine, just thermostat issue?

[MuleShack]

I believe the ON switch only controls the fan for the furnace. If you switched it to ON it would run FAN only regardless if the actual furnace was running.

If the room temp was 60 and the therm was set to 70 there is an issue unless the other switch was set to cool yet.

[Jim Almquist]

Make sure your pilot is lite. Those old style Honeywell thermostats with the mercury switch almost never fail but the newer digital are so much better because of the ability to program them.

[Nutty Fisherman]

on runs furnace, fan only runs fan. I think

[zamboni]

Pilots lit, its blowing hot when it is turned into the ON position.

[Jim Almquist]

If you short ( twist the wires together )the wires that connect to the thermostat your furnace should kick in and the would indicate that your thermostat is bad. Once you short the wires you should hear your burner kick on in the furnace and when it heats up enough it will kick on the blower.

In my case it was a blown out pilot light

[SkunkedAgain]

If you replace your thermostat and go digital, it's well worth it to spend the money on one that is extra programmable. Get one that is seven days a week at least. That way you can set most of your weekdays to be the same, but maybe the heat kicks on earlier Fridays (if you leave work early) and then different settings for the weekend.

[pikechaser]

Try this..next time is cuts out...dont touch the fan switch..leave it on auto...turn temp all the way down for a few seconds & then back to 70. If furnaace comes on & heat more than likely burner control is locking out because its not sensing flame & shuting down. By turning the stat down & then back up you are resetting the control. That may be what your doing now, kinda hard to say by your description. Will need to clean the flame sensor if if this is what is going on.