Dometic CCC2 Thermostat problem

Bobbo wrote:

TCI wrote:
Would replacing the unit work? On our old rig, 2001 Cardinal, we had to replace the thermostat 3 times.

Chuckle. I bought a new Airstream last April. Even before we took it out the very first time, the Dometic Air Conditioner stopped cooling. We took it back to the dealer, who replaced it under warranty. After getting the trailer back, the thermostat no longer showed the trailer as having a furnace. (It was an installation error by the dealer who didn't set dip switches correctly on the new AC, but that doesn't matter to this tale.) I took the trailer BACK to the dealer. During the process of trouble shooting just why the furnace no longer showed up on the thermostat, they took the thermostat off the wall. When they took the thermostat off the wall, the socket that the phone wire plugged into FELL OFF! The connector fell completely OFF the back of the thermostat. (I was standing there watching.) The thermostat would have failed soon. After replacing that thermostat, the furnace still didn't show up. They called in the manager. His first question was "did you check the dip switches?" Problem found.

1. The Tstat was broken partially by the first repair and found when they were too DUMB to realize why the furnace did not show up. Anybody that knows what they are doing KNOWS when you replace a Penguin, you MUST set the DIP switches. IF you replace and certain functions do NOT show up, you should realize you forgot to set the DIP switches. NOT pull the Tstat off the wall mount.
2. The Communication socket on the Wall tstat is very secure and takes a lot of force to break it loose.
3. Last, on a CCC system there is NO reason in the world to pull the wall tstat if you have lack of functions on the LCD display, especially after a Control board has been replaced. I would NOT use that shop again for repairs. Doug

TCI wrote:
Would replacing the unit work? On our old rig, 2001 Cardinal, we had to replace the thermostat 3 times.

Chuckle. I bought a new Airstream last April. Even before we took it out the very first time, the Dometic Air Conditioner stopped cooling. We took it back to the dealer, who replaced it under warranty. After getting the trailer back, the thermostat no longer showed the trailer as having a furnace. (It was an installation error by the dealer who didn't set dip switches correctly on the new AC, but that doesn't matter to this tale.) I took the trailer BACK to the dealer. During the process of trouble shooting just why the furnace no longer showed up on the thermostat, they took the thermostat off the wall. When they took the thermostat off the wall, the socket that the phone wire plugged into FELL OFF! The connector fell completely OFF the back of the thermostat. (I was standing there watching.) The thermostat would have failed soon. After replacing that thermostat, the furnace still didn't show up. They called in the manager. His first question was "did you check the dip switches?" Problem found.

TCI wrote:
Would replacing the unit work? On our old rig, 2001 Cardinal, we had to replace the thermostat 3 times.

Replacing a wall tstat is extremely rare. There had to be other factors if you replaced 3 tstats on your old unit. No, I will not state replacing it will fix the problem. Read my response again. IF you want to spend money and throw parts at it, then go ahead. But, odds are, you will be wasting money. Doug

Would replacing the unit work? On our old rig, 2001 Cardinal, we had to replace the thermostat 3 times.

Mandalay Parr wrote:
Try a master reset if you can.
Mine has temp sensors and circuit boards that can act up.

One of the BIGGEST misconceptions for the Dometic CCC system either 5 button or 10 button is a reset will fix OPERATIONAL problems. It does NOT. ALL a reset does is verify the DIP switch settings that communicate to the CCC. If you have NOT touched the DIP switches on the Boards, then a reset will not fix anything if you have an operational issue. Now, a reset WILL fix issues if the Upper board has been changed of messed with and the installer did not set the DIP switches correctly o failed to set the correct ones. Doug

1. Most CCC systems the CCC IS the Zone 1 temp sensor and the Zone 2 has a remote eye on a wall in the Zone 2 area
2. It is RARE for a CCC2 to malfunction
3. The most common cause is a corroded end on the Phone type communication cable connections.
4. IF you have Penguin model Roof AC units, the odds of corroded communication cable ends increases dramatically, especially after 3 years of operation.
5. You have these cables at both AC upper control boards and then the one on the wall ccc2 tstat. The corrosion will be very evident.
6. So, unless you want to pay and throw parts at it, you need a qualified RV Tech to check your system. Doug

Try a master reset if you can.
Mine has temp sensors and circuit boards that can act up.