Question about Honeywell Electronic Programmable Heat/Cool Thermostat - CT3300A100 Heater

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How do i change the battery on my honeywell thermastat?

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  • grisell915 Feb 01, 2010

    thank you sooooo much! it worked!



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You have to remove front cover. Most times there are little snaps on the sides of cover to undo. Get a smallish screw driver and pry the cover off very carefully. any more questions just get back to me ken

Posted on Jan 31, 2010

  • Ken Bledsoe Feb 02, 2010

    If you would just rate my help I would be forever in your debt. My ratings is what I live for helping people and when you see my numbers you know that I am knowing what I am talking about. Okay thanks



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Honeywell wifi thermastat 6980??

Try using the calendar and not the cakender set up. Just kidding make sure your press save after you change your settings. Also if that doesn't help doubt it will much try contacting Honeywell either by phone or web site they are very good at assisting contractors or homeowners with questions about a honeywell product.

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1 Answer

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the thermostat could be bad. It may have gone bad on its own or due to a short in the supply wiring. Sometimes mice will chew on the wiring in the wall that leads to the thermostat. But I wouls change the thermostat. They do go bad. Make sure you turn the inside unit off first in case you accidently touch wires together. This will blow the transformer inside the unit if the fuse doesn't blow first. I even scene thermostats with fuses inside. So you may want to take the thermostat apart and check for inside fuse also.

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Our air conditioning was working during the day. when one family member turned the air up from 72 to 75 she saw the screen process what she wanted and walked away. when another family member went to turn...

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