A/C problem

[Snomas]

My 2 roof top A/C units were replaced in November 2014 w/ new Dometic 15K units and also installed was an upgraded new thermostat. The rear unit will not come on. I checked the thermostat for inside temp on this unit and it reads 57 degrees. After calling a technician at Dometic HQ they determined that the unit itself is working (comes on when turned down to 50 degrees) so they said I need to have an A/C service technician check it out since the problem is in the controls within the unit itself . Has anyone had this type of problem and what was the fix?

[dougrainer]

Snomas wrote:
THX DOUG, my sensor & cover looks identical to the one in the link .

If I change the sensor, can I splice the new sensor to the existing wire?

YES. DOUG

[Snomas]

THX DOUG, my sensor & cover looks identical to the one in the link .

If I change the sensor, can I splice the new sensor to the existing wire?

[dougrainer]

First thing you do, is disconnect the Zone 2 remote sensor from the Board. That will make BOTH zones use the wall tstat for its sensor unless you also have a Zone 1 remote sensor. If the wall tstat is in a cabinet you will have a Zone 1 remote sensor. If the tstat is mounted on a wall inside the Tstat is the sensor. Regardless the Zone 2 will defer to the Zone 1 sensor. Then run and see if the Zone 2 AC operates at the higher temps(90 in the RV you set at 70 and it comes on). IF it functions correctly replace the Zone 2 remote sensor. The link shows the sensor and its cover. They also come in Black and brown, but odds are yours is white, Doug

http://www.dyersonline.com/dometic-ccc-and-ccc2-polar-white-20-remote-sensor-kit.html

[Snomas]

Doug, the new 2-A/C's were installed in 2014 w/ new thermostat, and it has worked perfect until now.

[dougrainer]

Snomas wrote:
Doug it's a 10 button tstat, the inside temp of the bedroom was 85 degrees when it read 57 on zone 2 on INSIDE temp button. Could be the sensor, where is the sensor located?

Zone 1 Inside temp button is reading within 1 degree for room temp and is working properly.

10 Button is the same as the 12 Button. The sensor should be on the wall in the bedroom area. behind a 1 inch plastic cover. THINK about it. IF the inside temp is reading 57 degrees, of course the AC will not come on until you go below 57 degrees. You need to provide more info. What has been done to the AC system and did you install NEW Penguins and that is the reason for the 12 button wall tstat? WHO replaced it and I assume the new system has worked since it was replaced until now? Doug

[sdianel_-acct_c]

our sensor is on the wall in the bedroom. The thermistor is inside the AC like this: http://www.adventurerv.net/sensor-kitremote-pi-15863.html When we had our front AC replaced the tech didn't hook up the remote sensor. Our thermostat is near the windshield (stupid) and that caused the front AC to run all the time and not cycle on and off. Once we added the thermistor that fixed it.

Our back AC wasn't coming on. We were told to: 1. reset the thermostat (directions online or in manual). 2. Put both AC fans on high in high temperature and high humid conditions to prevent coils from freezing up. 3. Check the voltage to make sure the voltage isn't going too low. We bought a plug in voltage meter. 4. Check all the connections (like phone cords), unplug, clean and plug back in. 5. Check coils to make sure they are clean. Our new AC that we had installed in 2014 already had dirty coils.

[Snomas]

Doug it's a 10 button tstat, the inside temp of the bedroom was 85 degrees when it read 57 on zone 2 on INSIDE temp button. Could be the sensor, where is the sensor located?

Zone 1 Inside temp button is reading within 1 degree for room temp and is working properly.

[dougrainer]

I assume you have the NEW 12 button wall tstat. The REAR AC has a separate temp sensor. So, IF the Temp is 57 degrees when you push the INSIDE temp button for Zone 2, It is probably NOT the tstat. The sensor for Zone 2 is the problem. WHAT is the actual temp in the Motorhome? Doug

[newman_fulltime]

if the unit cones on and runs correctly when the therm is put on 50 it tells me the therm is bad and nolonger calibrated correctly