Question about Honeywell Programmable Thermostat Heater

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Question what does -AC mean on my thermostat screen it keeps popping up and can't get unit to come on leo

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  • Anonymous Dec 17, 2008

    What does the -AC code mean? The air conditioning is off.

  • mensadoc Jan 07, 2009

    My Honeywell Chronotherm III was working fine until the code "-AC" abruptly appeared where the temperature display is supposed to be - makes no difference if the control is in "Heat", "Cool", or "Fan" position, nothing comes on.  I can't find anything about this in the manual, and changing the batteries had no effect.  Anyone got any ideas?



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A programable thermastst has different modes. in auto it can deside whether to apply heat or cooling. ac air coditioning. or you are in ac mode, but should notice the ac unit comming on. if no ac unit then of corese it won't come on :)

Posted on Feb 04, 2008


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If this was helpful please rate me.
Leo Ponder Appliance-Tyler,Texas

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