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Heater and A/C won't turn on

11174 Views 13 Replies 6 Participants Last post by  kenmac
Forgive me for any bad terminology. :)

My heat wouldn't turn on today. I have a programmable thermostat which has worked fine for a few months. I tried manually turning the temp up an additional five degrees from where it was and nothing happened - no heat and the fan didn't kick on either. I even tried turning on the central A/C and lowered the temperature to 7 degrees below the current temp and nothing happened. It doesn't look like any of my breakers tripped. I checked to make sure I do have gas (stove worked, hot water works) and my electric is working. Earlier in the week, the electric stacks on the side of my condo were replaced, but the heat has worked since then. The emergency switch for the gas burner is in the on position.

I'm really not sure what the issue is. Let me know if there is anymore info that is needed to help describe this problem.
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Does the thermostat make an audible click when you turn it up 2 or more degrees? Most electronic thermostats do when they cut in. You may have a bad thermostat or no power to your furnace. Post the make and model and serial # of the furnace.
Or a blown fuse or transformer in the furnace.
Sorry for the false alarm guys.

I actually did check all of those things before, but when my neighbor came home, I asked him about and it he checked the furnace - looks like the pilot light went out on the furnace. Sad part was, I had taken that panel off on the furnace and didn't even notice the pilot light wasn't on (probably because i've never seen it before, so I didn't know where to look). Not sure why it happened or if it'll happen again, but I was really concerned since the furnace and my a/c unit are both originals (23 years old). Not looking forward to replacing those just yet....

Thanks for the help guys!
Your A/C should have worked.. Pilot on furnace won't affect A/C
Yep, pilot has no bearing on A/C.

maybe when you switch to cool at the stat, you didn't wait long enough for the delay.
Well, I did drop the temp considerably on the thermostat for the a/c, but yeah, maybe I didn't wait long enough....

The heat has been heating since that pilot light was turned back on... will the heat work if the fan doesn't work? I though I read somewhere that it would, but it might cause something to burn out?
The burners will still light.
But, when the heat exchanger gets to hot. The safety will shut the burners off.

And yes, continued operation like that will damage the heat exchanger.

Same as constantly over heating your cars engine will damage it.
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Ok, just tried the fan. The temp in the condo (75) is well above the temperature set (70), it's set for heat, fan on auto. I turned the fan to On and it did turn on.

So, everything should be ok, right?
Doesn't matter what the temp is in the house.. When you turn t.stat switch to fan on you are sending power straight to the relay to power the blower motor.. So, yes it should come on
I was concerned because the fan wasn't coming on, even when set to on, when the pilot light wasn't on. I thought the fan would come on anyway whether or not the pilot light was on.
Fan should come on weather pilot is on or not when t.stat is set to the fan on position. Pilot off has no bearing on the fan on position on t.stat
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