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Topic: NO a/c NO A/H (Read 2223 times) previous topic - next topic

Re: NO a/c NO A/H

Reply #40 –
Thanks
Will do

Re: NO a/c NO A/H

Reply #41 –
Update:

As I had previously noted, this is an intermediate problem. When I did have power to the Comfort Control, I plugged in the Micro- Air Model 357 that was recommended to me. It, also, lit up. I reinstalled the original t-stat.

Yesterday, when I tried to fire up our air conditioner, there was no power. I had our Mobil RV repairman in my coach, working on my Microphor problem. We believe that the problem is with the control circuit board on the front unit. When I did have power to the t-stat, everything worked fine. He informed me that these boards are hard to find. In a past post, about replacing air conditioners three years ago, David S told me he got one on E-bay. I will be going up on the roof to find the model number of the board and try to find one, when we get back to the states. Can my existing board be repaired??

ALSO....I may want to sell the Micro- Air, since I don't believe it is the T-stat. Anyone wanna buy it from me, unused, new ????
When I get back to the states in May.

Getting warm here.

Re: NO a/c NO A/H

Reply #42 –
PIcture....

Re: NO a/c NO A/H

Reply #44 –
So I have a similar issues with my AC. I can turn on my 3 button thermostat and it lights up. BUT the view on the thermostat only shows zone 1. When I go to AC nothing happens. In investigation I disconnected the phone cable from the fron to rear AC and the front AC worked. Nothing of course from the rear. The 4 button duo therm of course still shows only zone 1. No zone 2. ALSO the front AC works but is continuous and the fan runs constantly. I did buy the duotherm 5 button thermostat and 2 control boards but have yet to install. Is there something simple that may be the cause before I go ahead and try the upgrade. Saw lots of talk about a fuse in the control board and phone wire going bad. Maybe the cause.
Help and knowledge would be appreciated!!

Re: NO a/c NO A/H

Reply #45 –
Hi Peter,

Your email mentioned 3 button and 4 button thermostats.

When the 4 button thermostat push buttons begin to fail, it temporarily scrambles the chip in the thermostat. Replacing the push buttons usually brings it back to normal, though occasionally resetting of the thermostat is needed afterwards.

Five button thermostats will not work with a 4 button A/C system. Hope you can return it or consider upgrading to a five button system - lots of work and greater expense.

Get hold of me for more help,

Jim Frerichs
308-440-5154

Re: NO a/c NO A/H

Reply #46 –
Sorry finger issues.  4 button and 5 button

Re: NO a/c NO A/H

Reply #47 –
I think that he said he had a 5 button tstat and new 5 button upper boards. Sometimes you can spray electrical contact cleaner on the cable ends and the couplers. The Dometic couplers are not the same as telephone couplers.

Re: NO a/c NO A/H

Reply #48 –
I just got done spraying contact cleaner and gently swabbing with Q Tip.
STILL no power to t stat. Went up on roof and opened front a/c unit. 3 amp fuse good. NO apparent corrosion or loose wires. will go check behind white panel tomorrow. Then....????????

Re: NO a/c NO A/H

Reply #49 –
Is there 12 volts at the 3 amp fuse? Thanks

Re: NO a/c NO A/H

Reply #50 –
Glenn,

If there is no 12 volts at the air conditioner fuse (to ground) then you might look for a fuse in the coach fuse panel (under the refrigerator?) or a tripped circuit breaker behind the white panel. If you are lucky your white book schematics might show 12-volt power for the air conditioner circuit boards. Also, you might check for a broken data cable, plug, jack, etc. either for positive or ground.

Jim

2002 U320 42'

Re: NO a/c NO A/H

Reply #51 –
My MO , when the t stat doesn't light up, is to leave the power switch "on". On two different occasions, I have come back, the next day, and there is power on the unit.

Yesterday, after three days of no power to the t stat, I went to bed with switch in the "on" position. I woke up, around 1:00am, to the sound of BOTH of my a/c's running, and the t stat lit up.
 Instead of simply turning off the power switch, as I usually do, I turned off each a/c unit in the mode setting. The t stat is still "on".

Soooooo.......Can I leave the t stat in this position, without causing damage to it?
                      ANYONE have any ideas as to what is going on with my power to the t stat. This is making me crazy. I will leave it on, as it is getting warmer here, in Mazatlan, unless I am doing something wrong.
 
Thanks. 

Re: NO a/c NO A/H

Reply #52 –
Symptom screams bad connection somewhere. Not sure of how to help you find it. My thermostat is always on and has been since we have owned the coach.

Re: NO a/c NO A/H

Reply #53 –
Quote from: GleamB –

1. .Can I leave the t stat in this position, without causing damage to it?
 2. ANYONE have any ideas as to what is going on with my power to the t stat. 

Glen,
1. Yes
2.  You need to check the on/off switch (on the thermostat) to see if the contacts are bad, if so replace (or have someone replace) the switch.

Mike

Re: NO a/c NO A/H

Reply #54 –

2.  You need to check the on/off switch (on the thermostat) to see if the contacts are bad, if so replace (or have someone replace) the switch

[/quote]
 
Problem is that when I plugged in the high dollarIT stat, it wouldn't light up, either. Now that the t stat is "hot " the new one works also.
That would preclude a switch problem, wouldn't it??

Re: NO a/c NO A/H

Reply #55 –
Glen,

If that is the case then I would be looking for a bad end on the cable that plugs into the tstat. and goes to the AC units. The ends are thriftly made but are simple to change out. New ends can be found at most any home improvement store (along with the crimping tool)

Mike
 

Re: NO a/c NO A/H

Reply #56 –
Glen,

The power (12vdc) that feeds the thermostat comes from a breaker that is located in the set of breakers that are hid behind the removable kick panel in front of the passengers seat. On your coach year seems like it is in the range of breaker #50 to 54 find the correct breaker for future troubleshooting. That is a self resetting breaker and it could be failing. IIRC that is a 5 amp breaker. Next time you loose power see if you have voltage on both sides of the breaker.  That breaker also has a second item feeding off of it but I don't recall what that is at the moment.

Mike