BAC Forum

General Boards => Technical Support => Topic started by: Bob Reeves on August 19, 2019, 10:53:54 PM

Title: loss of power to thermostat
Post by: Bob Reeves on August 19, 2019, 10:53:54 PM

07 Patriot thumder.
rear thermostat which on AC selects either bedroom or center Air conditioner. worked yesterday.  today worked for a while then quit. no power to thermostat. front working OK.  thermostats are on 12 V. are there fuses?  would the two thermostats be on separate circuits?  Any ideas?

Title: Re: loss of power to thermostat
Post by: Frank Bergamo on August 19, 2019, 11:01:23 PM

Bob,
On my 2002 Marquis, there is an inline fuse under the AC cover topside.
 Hope this helps.

Title: Re: loss of power to thermostat
Post by: Bill Lampkin on August 19, 2019, 11:02:29 PM

Try a 'reset' of the thermostat. Assume you have the original 5 button t-stat? I can't remember  the exact procedure (some help!) but it involves turning off the power to the t-stat (switch under bottom, I think) and holding two buttons down for a few seconds. I'll try to search for the procedure. Your '07, is the tstat controlled by the multiplex system? Different can of fish, there.

Title: Re: loss of power to thermostat
Post by: Bill Lampkin on August 19, 2019, 11:03:45 PM

Simultaneously depress and hold the MODE and ZONE push-buttons while turning the ON/OFF switch to "ON". FF should appear in LCD display until the mode and zone push-buttons are released

Title: Re: loss of power to thermostat
Post by: Bill Lampkin on August 19, 2019, 11:04:51 PM

Dometic troubleshooting guide: http://bryantrv.com/docs2/docs/ccc5.pdf

Title: Re: loss of power to thermostat
Post by: Robert Wagner on August 19, 2019, 11:39:58 PM

We had same problem.  It was a fuse and someone in here helped us with it.  The fuse was in the bathroom under the breakers. Don’t know where yours are but I would check that first. .  By the way it also worked out awning. 

Title: Re: loss of power to thermostat
Post by: Joel Ashley on August 20, 2019, 02:31:05 AM

See my photo in this thread:
http://beaveramb.org/forum/index.php/topic,9193.msg62896.html#msg62896

Thermostats on fuse #8 on our coach.

Joel

Title: Re: loss of power to thermostat
Post by: Bob Reeves on August 20, 2019, 03:50:41 AM

Frank & Bill &
Thanks for the prompt replies.
Have tried the reset per your instructions also checked the Dometic procedure ( the same). no result. will check to see if there is any incoming voltage. have not been up on top yet. also had read that there could be a fuse on a circuit board on the AC unit.
as the thermostats are on 12 V i have checked all 12 v fuses.

Title: Re: loss of power to thermostat
Post by: Bob Reeves on August 20, 2019, 03:54:56 AM

left coach for about 4 hrs. when i returned, i turned it on and it worked!  could it have frozen up and shut off?  any thanks for your suggestions.