Thermostat says heat is on, but it's not

Old 12-17-14, 08:31 AM
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Thermostat says heat is on, but it's not

I've been having problems with my heat not kicking on with my programmable thermostat. It only happens sometimes. The thermostat will say that the furnace is on, but it's not. If I flip the switch on the furnace off and then back on, it kicks on, but otherwise it's off even though the thermostat says it's on. This happens about once every two weeks or so. So I'm not sure why it happens sometimes and works just fine most of the time.
Old 12-17-14, 08:45 AM
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Welcome to the forum!! Is your thermostat powered only by batteries? If so, low batteries can cause erratic behavior such as you describe.
Old 12-17-14, 08:55 AM
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Welcome to the forums.

You haven't given us much to work with.

It sounds like the the furnace is going into trouble shutdown. Every time you turn it off and on you reset the control board. You'll need to check the furnace for a control board and check it for a red light. The control board may be in the blower section. You can open the blower to look for the board but in the future in order to read the codes you'll need to look thru the blower door sight glass as opening the door resets the board.

A make and model of the furnace can be helpful too.

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