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SJBailey
Sep 28, 2008, 06:51 PM
I have an electric furnace which I turn off in the summer. It turned itself on during a heat wave in spite of this. I have replaced the programmable thermostat with a new one and the furnace ignors the program. I have to turn off the circuit breaker to control having it on or off and it also ignors the required temperature. Any suggestions? :confused:

hvac1000
Sep 28, 2008, 10:13 PM
Look for a short in the low voltage control wiring.

SJBailey
Sep 29, 2008, 09:34 AM
Look for a short in the low voltage control wiring.


Thank you but I have NO IDEA how to do that - I am an electrically challenged person. Could you please give it to me step by step?

Are you referring to in the furnace itself? If so where do I look for this wiring please? There are two switches there labeled heat (high and low), fan (on and off) and a white one that says push to reset - but when I push it nothing happens (there is no resistance or any sound).

hvac1000
Sep 29, 2008, 11:39 AM
Firat is it just the blower that is turning on OR is the heat also on with the blower.

Aso the brand and model of your unit will help.

SJBailey
Sep 29, 2008, 12:06 PM
It is the heat as well as the blower -

It is an "InterCity" furnace serial # 178115

hvac1000
Sep 29, 2008, 12:43 PM
Just for your info

Innercity Products is marketed by Heil, Tempstar, Comfortmaker, Arcoaire, AirQuest, KeepRite, etc... now owed by UT (United Technologies). Who also owns Carrier, which markets under the Carrier, Bryant, Payne trade names... (they at one time marketed under Day & Night, and BDP).

Now the model number you supplied is incorrect try again. With out the correct exact number I cannot TRY to look up your furnace to see what it contains parts wise.

SJBailey
Sep 29, 2008, 01:31 PM
Sorry - that was the serial nuber that I gave you.

The Model number looks to be EL 15 or possibley 13 - I am pretty sure it is a 15 though.

hvac1000
Sep 29, 2008, 01:44 PM
I cannot locate the model number you posted but the first item I would check is the low voltage connections for a short circuit. Start by marking all the low voltage wires and where they land in the unit. Then remove the wires and see if the unit runs by itself. This will tell if the low voltage wires to the thermostat are shorted.

SJBailey
Sep 29, 2008, 01:57 PM
I cannot see ANY wires; nor do I have any idea where to look; or what the low voltage ones would look like if I did find them. Sorry but everything seems to be locked away behind the body of the Furnace.

hvac1000
Sep 29, 2008, 01:59 PM
If you cannot find them they are probably behind a access panel. It might be best for you to call for ON SITE help with your situation. You can get one heck of a shock or die from the electric contained in a electric furnace.

mygirlsdad77
Sep 29, 2008, 04:53 PM
Listen to hvac. You need to call either an electrician or hvac tech. I wouldn't be messing around with this stuff without at least a litte bit of knowledge of what you are working on. People go to months, if not years of training for this kind of thing. Best to call a pro. Sorry, but I don't want to see anyone electricuted for no reason.
Please call a professional and let us know what they found. Good luck.

SJBailey
Sep 30, 2008, 09:43 AM
Thanks very much for all your help - I guess I will have to do that. SB