Heat not working

[tileman2000]

Hi all....

This morning around 3 am I noticed it was very cold in the house.I checked the thermostat and it was down to 52.When I set the temp higher(70) It didn't do anything.Just now as I'm typing this,the heat kicked on,but it's blowing cold air.It's 15 outside so any help would be appreciated.

Thanks

[nukeman]

What type of heat? heat pump? gas?

If it is a heat pump, look for an emergency heat setting on the t-stat. That is for when there is a problem with the outdoor unit and uses only the heat strips.

[tileman2000]

It's gas heat.The unit is only 3 years old and this is the first time this has happened.

[nukeman]

I don't have much experience with gas. It sounds like in the 2nd case, the blower is coming on, but the burner isn't. In your 1st case, neither is coming on. If you have a multimeter, you could check that the furnace is receiving a signal from the t-stat calling for heat. That would rule out a t-stat problem.

Hopefully someone with more experience with gas furnaces can give more advise. It may help to post the model and any other info you can on the furnace. If you have other gas appliances, do they work? Just to rule out a supply problem. Not likely, but something to check.

[Jeff1]

Is the igniter working? If its like my old one, its ceramic and if it breaks the blower starts, it tries to light and fails.

[jadnashua]

All sorts of reasons a furnace might not come on. If your thermostat has battereis, you might replace them. If the furnace is closed combustion (i.e, uses pvc for air intake and exhaust, the pipes could be closed off in ice or deep snow or any number of things. The igniter could be bad, the pressure switch, the gas valve. On many of the newer furnaces the control board has indicator lights that show what's going on either through lamps on/off/flashing. Your manual is the best source of info on troublshooting.

[Hube]

Hi all....

Just now as I'm typing this,the heat kicked on,but it's blowing cold air.It's 15 outside so any help would be appreciated.

Thanks
Are you saying that the heat (meaning the burner) came on, but it only blew cold air.
How long did it finally take to get heat or was there no heat at all even with the burner operating?
I think a better description of your problem may help us to give you some worthy advice to your problem.