Dometic thermostat troubleshooting

Dometic thermostat troubleshooting. It is really annoying if problems occur with your RV thermostat ac unit and it prevents working, and if it’s midnight time, it becomes more frustrating because you can not do anything at midnight.

A lot of troubles can occur with the Dometic thermostat, like faulty circuit board, the appliance not switching on, etc., but you can fix most issues with the RV air conditioner unit by yourself.

I have been using a Dometic thermostat for one year, and that is the reason I am writing this blog post to share with you various troubleshooting tips that you can use for a Dometic Thermostat.

Dometic thermostat troubleshooting

A thermostat is an appliance installed in an RV air conditioner. The primary purpose of a thermostat is to tell the cooling or venting system how much and when to work.

When a thermostat prevents from working, a number of problems can occur to the duo therm thermostats; the most usual issue that occurs to the RV is that it does not stay on or not remains at the set temperature.

When you see your Dometic RV thermostat not working efficiently, it becomes very difficult to find the main culprit.

This article will help you a lot to find the origin of a duo therm thermostat failure, so keep reading.

Testing duo therm thermostat setting

testing duo therm thermostat setting

Inspect the range of the dc volt after turning on the duo therm thermostat setting. The range of dc volts must be 10v to 30v.

The reset operation will inform you if the appliance has a wiring issue. The thermostat panel itself can tell the main issue through an error code.

If the device is not working correctly, you can easily sort out the issue through the error code that appears on the digital display screen.

If the device is still not working properly after the right configuration, you need to get a new duo therm thermostat.

The appliance does not turn on

It is a very frustrating condition when there is hot weather and the air conditioner does not turn on. The basic cause beyond this issue might be that the ac is not getting the power supply correctly.

If you have switched on all the heat strip dip switches and still the air conditioner is not turning on, remove the ac from its main link.

Sometimes, the rv thermostats switch on due to a problem with your wall outlet. If there is an issue with the wall outlet, like the circuit breaker is tripped or the outlet burnt out, then ac unit does not switch on.

You can use a voltmeter to confirm the electric current in the wall socket is right. If the electric current values are incorrect, use another connection in the room to turn on your appliance. If there is no other major issue, the Dometic thermostat should start cooling now.

Unit won’t stay on

unit won't stay on

Some digital thermostat users complain their device does not turn on, or if it turns on, then it won’t stay on and switches off automatically.

If it switches off repeatedly, your rv thermostat strikes a crack on the road.

Check the solder joints because a cracked solder joint in the power switch can be broken in this case and create the issue of switching off after some time for the air conditioner.

To stop its damage, resolder the button with a 25- watt soldering iron.

On occasions, the user has to change the damaged wiring due to a short circuit. You must contact a skillful electrician to change the wiring because it is very dangerous to change the wiring by yourself.

However, if you are professional, switch off the power supply or ac power before replacing the damaged rooftop ac wiring.

Reset system operation

A system reset protocol can also fix your issue. If you want to troubleshoot this problem yourself, check the device fuses, especially those below the rooftop of your rv thermostat.

If you see the fuse is blown away, then immediately replace it to get things going well.

Inspect gas leakage on ac unit

inspect gas leakage on ac unit

Air conditioners mostly face electrical error issues. Nevertheless, some users have gas leakage issues with their ac units.

A gas volume is installed in the duo therm thermostat that chills the hot air in the appliance. If this gas starts leaking out, you will feel only hot air is coming out of the unit.

In this situation, immediately contact a skillful professional to repair the device. You can also contact directly with the Dometic company for assistance.

The repairer will inspect the gas tank and repair it from the place where the gas is coming out and leaking.

After repairing the gas tank, you can refill it. It will take some time, but after properly repairing the gas tank and refilling it, you can get start the ac to get the cooling again.

Faulty push buttons

faulty push buttons

It usually happens with every device that its push buttons become faulty and start working badly.

The same is the case with the rv thermostat zone and mode buttons; they start working properly after some time.

The main cause beyond push buttons’ lousy performance is the build of too much dust under the push button or switches.

The build-up of too much dust is apparently due to your rv thermostat being on the road most of the time.

You can start your checking through rubbers under the push buttons. These buttons pull the dust like a magnet attracts magnetic things. Remove the dust and debris from them with a contact cleaning solution.

First of all, clean the dust from all buttons and switches. Then, detach the system power module boards and pin the tabs. You can easily do it with a small flat screwdriver.

You can use a spray contact cleaner to clear all the dust. After that, check the push buttons are working properly.

Wrong temperature set point

wrong temperature set point

Sometimes, the air conditioner starts malfunctioning, like the ac is not displaying the current temperature or even functioning below the correct temperature.

Usually, it is difficult to troubleshoot this problem but not impossible, so you can also do it with slight hard work.

The main reason for the air conditioner giving the wrong reading is an issue with the remote sensor or temperature sensing.

If you want to identify the issue by yourself, then take a current air temperature reading with a thermometer from various corners of the room before the air conditioner comes on.

Now, check the temperature reading from the same corners when the appliance switches off. It must be a reading of +/- 3 degrees.

If the gap is larger, then you should do a system reset to get the thermostat to operate

Troubleshooting e1 error code

If the e1 error appears on the control board or display screen, it means miscommunication between the individual power board module and the CCC2 thermostat.

The code must accommodate the lost communication zone, and details must pop on display.

Now, to solve this issue, execute the system reset protocol. If this does not make any change and solve your problem, then track down the wire from the duo therm thermostat to the rooftop ac.

Inspect the connections from both ends and ensure that they are tightened from both ends. Remember, if you pull out the wire, then you will have to perform a system reset.

Reset Control Panel on air conditioner

reset control panel on air conditioner

If you are having issues with the touch panel of your duo therm thermostat, the device must have a configuration error.

The simple way to solve this trouble is to open the thermostat settings and inspect the reasons behind the issue.

If you have recently made any configuration changes, then return to the previous settings.

Take a small pin and hold it inside the pinhole on display. After some time, your duo therm thermostat must be reset, and your issue is solved.

Rv thermostat is bad

rv thermostat is bad

If your duo therm thermostat is showing a black screen or the temperature does not match the thermostat setting, then these are the main symptoms of rv thermostat being bad.

If the screen is not displaying the last temperature set point on your digital thermostat, then there is not strange that your thermostat is bad, and you need to repair it.

Warranty claim

If you have a new thermostat and it is still not functioning after applying the above troubleshooting tips, then contact the dealer to forward a warranty claim to the company.

If the warranty date is not over, you can get a company guideline or free repair services.


The bottom line of the article is that if you have a duo therm thermostat and it is not working properly, then if you want to solve the trouble by yourself, it may be risky and dangerous.

Hence, contact with a professional repairer or Dometic is your best bet.

The Domenic support team will surely help you when they diagnose the main issue with the thermostat. Remember that this process will take some time, but your problem will surely be solved.

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