Yes, I have a problem on my Honeywell Chronotherm III t-stat
- showing "-AC" on top right hand corner, where used to be current temp. The t-stat is used to control both AC and heater, and the problem happens on both "heat" and "cool" setting. I
have tried to switch the front part from another working t-stat with
same model, it has the same problem. But If it's not a problem on
t-stat, how can both AC and heater have problem at same time? Can
anyone help? Thanks.
-   My system is turned off at the thermostat but as I walked by I noticed that next to the date and time is a long dash (-) followed by AC. If I turn the system on cool, the fan motor never starts up and the dash and AC still stay there. It is going to get hot here soon. Please say this is a thermostat problem!
-   i have a honeywell chronotherm III which is no longer working. i get a HOLD -AC indicator where the temperature (i.e. 70 and heat would normally appear). there is no air (hot or cold) coming out. we've changed the battery as well. not sure what's wrong - but our others work fine.
-   swatirwarren
What you can do is try and clean the contacts. Open the door on the thermistat and remove the two screws, after that you can seperate the part that is mounted to the wall and the front panel. Look at the part that is mounted on the wall and you'll see the contacts that should be a copper color. They might be black from age. Clean them and you'll be surprised how well it will work after that.
"Possibly" the controller to the T-Stat is shut off. We just had that problem but we had rented the basement and we think the tenant shut off the unit over night.
I have one humidistat honeywell H8908B which presently controlls honeywell humidifiers(HE440A ). I...
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I have one humidistat honeywell H8908B which presently controlls honeywell humidifiers(HE440A ). I am adding the HM512 onto the second furnace and trying to wire into the exisiting 440a. the 440a presently controlls both furnaces and works ok. can i wire and make the HM512 a slave ? and it still has to fill up with water an shut off by itself. i want both to act as one,but having the 440A keep controll of the fans. the service tech added a seperate two pole relay and spiced into to blue wire on the 440 and one side of the humidistat conector. also he set the number 4 dip switch on. this wiring left me with a over heating 512, it was super hotn to touch on the outside of the unit eventhough the main 440A was off.please help
I am getting six blinks on the call for service light after I push the reset button.What does that...
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I am getting six blinks on the call for service light after I push the reset button.What does that mean?
Chronotherm III...Replace Battery notification blinking...replaced twice with the appropriate...
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Chronotherm III...Replace Battery notification blinking...replaced twice with the appropriate batteries, turned the correct way. Cleaned off the battery terminals and still have replace battery notification?
"replace better" msg light came on; I replaced with 3 AAA Alkalines...3 days later, same...
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"replace better" msg light came on; I replaced with 3 AAA Alkalines...3 days later, same message- replaced AAAs again, with what are absolutley fresh ones, same msg. Is there a backup batter somewhere on this unit that needs replaced? The manual does not indicate or show or mention a backup battery...stumped, 'HEP! thx, ed zeppelin the temperature guy