A multitude of problems that your Dometic thermostat can have might be solved by troubleshooting it.

Since the issues may sometimes be solved without contacting for assistance, it should be the first thing you do.

Once you’d carried out some straightforward troubleshooting steps, they would swiftly clear.

The many methods for troubleshooting typical issues with these thermostats are provided in the guide that follows, along with instructions on how to carry out specific tasks.

How Can I Reset My Dometic Thermostat for an RV?

For thermostat reset:

  • Check to ensure that the Single Zone LCD Thermostat is set to the Off Position.
  • Press and hold the “+” button for three seconds while simultaneously pressing and holding the On/Off Mode button. When the LCD displays -, push the On/Off Mode button one more to switch the system off. The system startup is now complete.

How Can I Reset My 5 Button Dometic Thermostat?

  1. Turn off the switch.
  2. Press the mode and zone buttons simultaneously as you flip the switch back to ON.
  3. As you do this, the digital display should show the letters FF, and they will stay there until you let off of the zone and mode buttons.
  4. Hold down the zone and mode buttons until you see these letters, then let go of the buttons. Your computer should have been reset and be ready to use.

The Meaning of Every Dometic Thermostat Error Code

The Dometic thermostat shows a number of codes to show the system’s status or any problems. The numerous error codes and their meanings are listed below:

  • E1: The thermostat and all system power module boards are unable to communicate. The system will end.
  • E1: The thermostat and one specific system power module board are no longer in communication. The “E1” error code and the zone’s lost-communication zone number will be shown on the LED. Along with the present zone, any other zones that have a communication breakdown will also flash.
  • E2: Indoor temperature sensor is open or out of range. All heating and cooling functions will be disabled. The manual fan will still run.
  • E3: Indoor temperature sensor that is shorted. All heating and cooling functions will be disabled. The manual fan will still run.
  • E4: Out-of-range or open circuit outdoor temperature sensor (select models). Operation of the heat pump will be disabled. The functionality of the furnace, heat strip, air conditioner, and fans will not change.
  • E5: Out-of-range or open circuit for the freeze sensor. Operation of the air conditioner will be restricted. The latest temperature set-point is shown but heat pump, furnace, heat strip, and fan operation may continue.
  • E7: All of the system’s power module boards lose their 120 Vac power. The device will turn off.
  • E8: Invalid zone configuration. In one zone, the ON position is selected on the DIP switches for the heat pump and the heat strip. In the impacted area, heat pumps, heat strips, and air conditioners won’t operate.
  • E9: Invalid zone configuration. In one zone, the ON state is selected for the dehumidifier DIP switch as well as the heat pump or heat strip DIP switches. The affected area will be shut out of the functioning of the heat pump, heat strip, and air conditioner.

Common Issues with Dometic Dual Zone Thermostats and Solutions

Error Code E1

This error number denotes a breakdown in communication between the power module boards or a specific power board module and the CCC 2 thermostat.

The zone that has lost contact should be identified in the code, and that information should show up on the display.

The original code will display flashing next to any new zones that have lost connectivity.

The system reset procedure should be used as the first option to attempt to solve this issue.

If it does not resolve the problem, you must identify the wire that runs from the thermostat to the rooftop air conditioner.

You must do a system reset after unplugging the cable, so check both connections to make sure they are secure.

The thermostat should be replaced if a system component has failed since it might possibly be the cause of the problem.

#1. Not Functional Buttons

If your Dometic dual zone thermostat’s buttons don’t appear to be functioning, there may be too much dust within the thermostat or on the buttons.

Start cleaning the switches after removing the cover to solve this issue.

Then, using a little screwdriver, peel off the buttons to reveal the contact points.

Use some Q tips and contact cleaner to clean them.

#2. The Thermostat Will Not Turn On Or Remain On.

Your ON/OFF switch is the first place you should check.

No electricity will reach the switch if the solder used to make the connection is cracked or fractured.

Additionally, ensure that none of the other solder joints are damaged or cracked by inspecting them all.

Simply use a soldering iron to replace the old solder in order to solve this issue.

#3. AC Not Reaching The Appropriate Temperature

Before the AC turns on, take several readings with a portable thermometer around the room to identify the issue.

When the gadget goes off, take another reading at the same spots.

Only a reading of +/- 3 degrees is acceptable.

To get the thermostat to work, you need do a system reset if the gap is bigger.

Typical Dometic Analog Thermostat Issues and Solutions

#1. Wiring Issue

Your thermostat may sometimes not operate or function as it should due to a wiring issue.

Take a voltmeter and see whether the thermostat is getting any electricity at all to begin troubleshooting this issue.

If there is no current entering the device, then there is probably a wiring issue.

Using a voltmeter or tester, you must determine where the wiring could be broken.

If you are a handyman, you may repair it yourself; otherwise, get a specialist to fix the wiring.

#2. Ineffective Heat Or Air Conditioning

Your thermostat may not be working properly if your air conditioner or heater won’t switch on or shut off.

For an analog thermostat, slide the slider in the desired direction well beyond the present temperature.

If there is no audible “click,” the issue is probably with your thermostat.

Your heater or air conditioner will need to turn on when you hear a “click,” which is a relay closing.

When your room has reached the proper temperature, plus or minus one or two degrees Fahrenheit, you should also hear a “click.”

It’s conceivable that the problem is not with your thermostat if you hear a “click” sound.

To be sure your thermostat is not the issue, you may continue on your investigation.

What Is The Process For Resetting A Dometic Comfort Control Thermostat?

Your Dometic Comfort Control thermostat’s factory default settings are restored by performing a system reset.

The thermostat will need to be reset in the case of system memory loss or dip switch configuration changes.

Follow these procedures to do a system reset on a Dometic Comfort Control thermostat:

  1. Ensure that the thermostat is set to the OFF position.
  2. Next, hit the MODE and ZONE buttons at the same time. The LCD will show “IniT” and each zone that is accessible.
  3. Release the buttons for ZONE and MODE.
  4. To end system configuration, press the ON/OFF button.

How To Activate/Deactivate The Dometic Comfort Control Thermostat

When the backlight is off, switch ON the Dometic Comfort Control Center (CCC 2) thermostat as follows:

  • Press any button to activate the thermostat first.
  • Press and then let go of the ON/OFF button. The most recent programmed settings will shown on the LCD.

In order to deactivate the CCC 2 thermostat:

  • On/Off button pressed; then release.
  • When the thermostat is set to OFF, just the time of day will be shown.

How To Recognize A Malfunctioning RV Thermostat

There are a number of indicators you may look for to determine whether your RV thermostat is malfunctioning or not functioning at all:

#1. The Temperature Is Not What The Thermostat Is Set At

If you discover that the temperature you set on your thermostat does not match the temperature of the room, the thermostat may be defective and not be transmitting the signal correctly.

Start by confirming that the temperature shown on the thermostat and the temperature within the room are the same.

To check the temperature of the room, you will want a different thermometer.

If the readings are off, there will be a problem.

For instance, the air conditioner won’t cool since it believes it is already cool.

#2. The Thermostat Panel is Blank.

Another indication that a thermostat is defective is when the screen is blank.

It seems sense that the temperatures have been the same for some time if you have a digital thermostat and the screen is not displaying anything.

#3. Ineffective Heat Or Air Conditioning

When the heat or air conditioner won’t switch on or off, this is another symptom that there is a problem with the thermostat and that it may have become faulty.

Reduce or raise the temperature on a digital thermostat by at least 10 degrees above the ambient temperature.

A relay should “click” when it closes, signaling the heater or air conditioner to switch on.

If you don’t hear the click, the issue is probably with your thermostat.

Dometic RV Thermostat Manual Videos Suggesions From Youtube

Dometic Thermostat How To Use – Darian Pellicciotti
Dometic Single Zone LCD RV Thermostat – How to Operate and Demonstration – RV Habit
How to Use Dometic’s Digital RV Thermostat – Minard’s Leisure World

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Written by Bob Matsuoka
Bob Matsuoka is a blogger and founder of RVing Beginner blog. He has been blogging for over five years, writing about his own family’s RV adventures, tips for people who are interested in buying an RV or taking their family on an adventure by RV.