Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 09-02-2008, 10:24 PM   #1
Newbie
 
Join Date: Sep 2008
Posts: 3
Rewards Points: 0
Share |
Default

Help with Chromotherm III Showing -AC


My thermostat is showing the -AC which is supposed to mean that it is running on temporary battery power. I am not sure why this just started happening. We have not had any power failures and the fan on the furnace unit continues to run and moving the fan control to auto has no affect. The AC unit does not come on even though the setting is well below the current temperature.

I can move the selector switch back and forth between auto and on for the fan control and the -AC goes away temporarily, the system light comes on and then back to the -AC.

Please help. I suspect something at the unit rather than with the thermostat.

TIA

Mike

mcnoche is offline   Reply With Quote
Old 09-02-2008, 11:17 PM   #2
Electrician
 
SD515's Avatar
 
Join Date: Aug 2008
Location: Near Jackson Michigan Area
Posts: 1,450
Rewards Points: 0
Default

Help with Chromotherm III Showing -AC


Try turning off the t-stat (heat/off/cool), and checking that it is properly mounted. Maybe the pin connectors aren't making good contact. Try turning the furnace off at it's switch for 15 or so seconds then on. Sometimes it can reset the furn board. Update us if that doesn't help. Does the furn have a circuit board, and can you see a flashing light?? How many blinks?

SD515 is offline   Reply With Quote
Old 09-02-2008, 11:41 PM   #3
Newbie
 
Join Date: Sep 2008
Posts: 3
Rewards Points: 0
Default

Help with Chromotherm III Showing -AC


Thanks for the reply.

I have tried taking off the t-stat...cleaning what I can and replacing it to no avail. I tried your suggestion of turning off the unit using the switch at the furnace and same behavior. When I turn the switch back on the fan starts up and no control over the AC unit.

I do not see a board with lights...I see a board where the t-stat wires are connected but there are no lights on the board.
mcnoche is offline   Reply With Quote
Old 09-03-2008, 12:45 AM   #4
Member
 
HvacWiz's Avatar
 
Join Date: Nov 2006
Location: Northwest Ohio
Posts: 286
Rewards Points: 0
Default

Help with Chromotherm III Showing -AC


The stat you have is old and outdated, I have replaced many of these stats over the years because of problems you describe. Replace the stat and all will be fine
HvacWiz is offline   Reply With Quote
Old 09-03-2008, 07:48 AM   #5
Newbie
 
Join Date: Sep 2008
Posts: 3
Rewards Points: 0
Default

Help with Chromotherm III Showing -AC


I am willing to do that but I was unsure if there was anything wrong with the furnace piece before I wasted money on a new t-stat. I was about to call someone out to take a look but would much rather go with the installation of a new t-stat.

Mike
mcnoche is offline   Reply With Quote
Reply

Tags
-ac, chromotherm, honeywell, thermostat


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wall studs showing through sheet rock js1971 Remodeling 7 09-11-2008 05:45 AM
Granite tile and BIG probs with adhesive showing through deeaa Building & Construction 6 07-30-2008 12:44 PM
Chromotherm III Wiring gronk HVAC 4 02-06-2008 04:08 PM
Showing off my basement framing pics...... yummy mummy Building & Construction 103 03-17-2007 02:41 PM
honeywell chromotherm thermostat - help? mkbgriffen HVAC 4 12-26-2006 12:46 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.