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LCGarrett 10-11-2010 12:56 AM

Help.. Heat automatically coming on at night
I had a brand new Amana split gas unit installed about a year ago. Outside temperatures here are currently reaching 75 to 80 during the day, and dropping to lower 40s at night. I have been leaving my ac on during the day, but at night the gas heat unit is automatically turning on and runnning constantly, even though the thermostat is still set to cool and 70 degrees. I woke up at 2 this morning to find my house at a blistering 87 degrees! Any suggestions?

kok328 10-11-2010 05:36 AM

Bad Thermostat?

LCGarrett 10-11-2010 07:49 AM

Maybe.. I know the unit has some sort of temperature sensor that causes it to switch from auxilliary to gas heat when it drops below x degrees outside, when I am actually using the heat... but it seems to me that it shouldn't kick on the gas furnace if I have my thermostat set to cool. Could it possibly be that the contractors wired something wrong? Not an hvac expert by any means, just trying to work this out logically. The thermostat correctly determines inside temp and displays it. Basically unit is set to fan auto, cool, and 70 degrees. It seems to me that the thermostat is working as it should. I had no problems all summer long with the unit, cool cycle worked flawlessly, keeping the house right at 70. Its only now when it gets cool at night that this is happening. The unit should simply stay off if it gets below what I have set on the thermostat, but because of some flaw when the outside temp sensor reads its below x degrees the unit thinks it should turn on the gas furnace. Its as if its completely ignoring the thermostat settings.

paul52446m 10-11-2010 09:09 AM

Are you sure that you don't have a auto. change over stat, and you have it set on auto. later paul

woodchuck 10-11-2010 02:32 PM

I have a new amana and there is a setting on the thermostat you can scroll thru cool, heat, off and auto. If it's set on auto it will run the a/c or heat depending on the inside temp and the setting you have the a/c programed for and the setting you have the heat programed for. If it was programed for 87 that's what it would make it. I have my a/c programed for 73 and my heat for 65 overnight and 70 starting at 6am. So it may come on after a cool night but it just takes it to 70 and during the day it won't get above 73.

There is another auto setting for the fan. I can choose auto or on.

LCGarrett 10-11-2010 02:38 PM

My thermostat only has an auto setting for the fan. Its set on cool but gas furnace continues to run nonetheless. Clearly says "cool" when the heat is blasting.

paul52446m 10-11-2010 03:39 PM

sounds like your stat is not working right. Are you sure that all your programing is right? Later Paul

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