A/C wiring issue on 2012 International

[Martin R]

I have a 30ft International with 2 Dometic A/C units. After a long trip that culminated in me plugging in the trailer in the driveway to our home 50amp shore power and going to bed leaving the A/C working fine, I awoke to a dead thermostat control panel. Thinking this was a Dometic issue I took the trailer over to Camping World who found a dead circuit board in the rear A/C which they have replaced. However there is still no power between the thermostat control unit and the A/C unit. When removed from the wall and attached directly to the circuit board the thermostat control unit registers fine and the A/C operates. There also does not appear to be any signal between the 2 units with the thermostat displaying an E1 error message. They suspect a power surge as the root cause. They have no Airstream experienced personnel and are uncertain of the routing and the best means of removing and replacing the cabling between the thermostat and the rear roof unit and similarly between the two units themselves. Any advice or suggestions at the best means of approaching this rewiring issue would be much appreciated as I am fearful of the potential need to start cutting some new holes in the aluminium....The nearest Airstream dealer is not accepting any new appointments until February 2016 but that's another story. I have addressed the question to Jackson Center but no answer yet.

[AstroBruce]

Doesn't sound probable that three problems occurred at the same time. You need to find someone who knows what they are doing to diagnose the problem.

Bruce

[Martin R]

I am not qualified to judge the likelihood of one event such as a power surge/lightning strike
causing multiple issues but I was shown the burned connection on the A/C replaced circuit board and had a demonstration of the Comfort Control unit (thermostat) working whilst attached to the A/C unit with the replaced circuit board directly rather than from its wall mounting where it was dead. Similarly I had a demonstration of the E1 message which I believe notes a communication error between the two units. Thus the belief of the Tech that the remaining problems lie within the 2 communications type cables: one from the wall mount to the A/C unit circuit board and the other between the 2 A/C units. Not knowing the wiring schematic for these communications type cables ( a light tug on one end did not yield any movement on the other) and never having working on an Airstream he has prudently put the work on hold until I/we can get a much better feel for what trying to pull and then replace the existing flat communications type cables really entails. It is not proving to be the straightforward issue I had expected when I took the trailer to CW because they happened to convenient Dometic authorised services and it could be the problem is something other than their diagnosis suggests. Unless someone here can reassure me that the replacement of these communications type cables is in fact much easier task than appears to be the case and that given the right input CW and/or I can do the job without risking any further negative impact on the trailer then clearly will have to seek greater expertise- hopefully not forcing me as far North as Jackson Center.

[lewster]

The only way to positively tell if the comm. cables are bad is to run new cables from unit 1 to the CCC and a second from unit 1 to unit 2.

These will be test cables and run directly between the units and CCC and not thru the walls/ceiling YET.

If all is operational, then you try to eliminate one cable at a time to see if it is one or both.

This method gives you quick analysis of your comm. cables and will tell you which ones need to be replaced.

The bad news is that it is almost impossible to run new lines without panel removal.

Good luck!




Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[Martin R]

Lew, many thanks your comments which make sense to me. I will try and get the diagnosis confirmed or otherwise using your methodology. Your comment as to the near impossibility of rewiring the comms cables without removing panels is not the greatest news but I had a suspicion this might be the reality. If the diagnosis is correct and interior panel removal is inevitable then the next challenge will be to find somewhere, hopefully closer to South Florida than Jackson Center, that can be trusted to do the work properly. If you or anyone else
have any suggestions or recommendations in this regard I would love to hear. My contact with the AS dealerships from around Tampa and South has been limited but I have not been bowled over by my experience. Looking further North I have heard much more positive comments about the guys in the dealership in Alachua, FL but have no first hand experience and would welcome any recommendations for somewhere that can be trusted to handle the rewiring/interior panel work less than the 20 hour or so drive to Ohio.

[lewster]

I would definitely look to Sanders in Alachua rather that the Tampa dealer or North Trail in Ft. Meyers.


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[manseyr1]

Try RV Renovators in Pinellas Park FL. They have lots of Airstream experience and perform all the work on my Airstreams. 727-521-1161. Mom and Pop operation very professional and honest.

[Martin R]

I appreciate the suggestion of RV renovators. I had a look at their Facebook page and from what I could see they could well prove to be a good outfit to have on file. Yesterday, after the Tech CW confirmed he had tested according to the methodology suggested by Lew Farber I spoke with JD Sanders in Alachua and made an appointment for repair at the end on November.

[xrvr]

Sanders, give them a call. They are busy, too, but will help.

[GandW]

I agree on staying away from Tampa.