What does the flashing check light on my Dometic fridge mean?

The flashing check light indicates that the refrigerator has failed to ignite on LP gas mode after multiple attempts. The control board automatically tries to light the burner several times, and if it cannot establish a flame, it locks out and triggers the flashing check light as a safety precaution. This is one of the most common alerts on Dometic absorption refrigerators.

How do I reset the flashing check light on my Dometic fridge?

To reset the check light, turn the refrigerator off completely, wait about 5-10 seconds, and then turn it back on and select LP gas mode. On some models, you can press and hold a dedicated reset button on the control panel. If the light continues to flash after resetting, there is likely an underlying issue with the gas supply, igniter, or burner assembly that needs to be diagnosed.

What are the most common causes of the Dometic fridge check light flashing?

The most common causes include an empty or closed LP gas tank, a faulty or dirty burner assembly, a weak or failed igniter board, or a clogged burner orifice. Air in the gas lines after the tank has been refilled or reconnected can also prevent ignition and trigger the check light. Additionally, a dirty flue tube, spider web blockages, or a failed thermistor can contribute to this problem.

Can I still run my Dometic fridge on 120V AC power if the check light is flashing?

Yes, in most cases the check light only relates to a failure on the LP gas mode, so switching to 120V AC electric mode should allow the fridge to continue cooling normally. Simply select the AC or auto mode on the control panel, and the electric heating element will take over. However, you should still have the gas-side issue diagnosed and repaired to ensure full functionality while traveling or dry camping.

When should I call a professional to fix the flashing check light on my Dometic fridge?

You should call a certified RV technician if the check light keeps flashing after resetting, if you smell gas near the refrigerator compartment, or if the unit fails to cool on both gas and electric modes. Working on LP gas appliances can be dangerous without proper training and tools, and an improper repair could lead to a gas leak or fire. A technician can safely inspect the gas valve, igniter circuit, control board, and burner assembly to pinpoint and resolve the issue.

Dometic Fridge Flashing Check Light — RV Diagnostic Guide

Probable Causes

The "check" light on a Dometic RV refrigerator typically indicates a failure on the gas (LP) side of the cooling system. The most common causes include:

Failed or dirty burner assembly — soot buildup or debris blocking the burner jet
Faulty thermistor (temperature sensor) on the cooling fins
Bad igniter or electrode — no spark reaching the LP burner
Control board failure — the board detects repeated failed ignition attempts and locks out
Gas supply issue — empty tank, closed valve, air in the line, or a kinked supply line
Blocked flue or baffle — insects, rust, or debris obstructing exhaust flow
Weak or failed gas valve/solenoid on the fridge itself

Urgency & Safety

Moderate to High. Any LP gas issue carries a risk of gas leak or incomplete combustion producing carbon monoxide. Do not repeatedly try to reset the board without identifying the root cause. If you smell propane at any point, shut off the LP supply at the tank, ventilate the area, and do not use any ignition sources.

DIY Difficulty

Moderate — Most diagnostic steps require basic tools and observation. Burner cleaning and board resets are straightforward. Gas valve replacement or control board work is more advanced.

Typical Repair Cost

| Repair | Estimated Cost | |---|---| | Burner cleaning / flue service | $75–$150 (shop) | | Thermistor replacement | $30–$80 (part + labor) | | Igniter/electrode replacement | $50–$120 | | Control board replacement | $200–$450 | | Gas valve/solenoid | $150–$300 |

Parts You May Need

Dometic burner jet/orifice (model-specific)
Thermistor (clip-on fin sensor, check your model number on the data plate inside the fridge compartment)
Igniter electrode and wire assembly
Dometic control/power board (e.g., Dometic 3850712.013 or equivalent for your model)
Fine wire brush or compressed air for burner cleaning

Step-by-Step Diagnosis

Reset the board first. Turn the fridge off, wait 10 seconds, then turn it back on and select LP mode. Watch and listen at the rear exterior access panel. You should hear a clicking sound (igniter) followed by a visible flame through the burner inspection window. If the flame lights but goes out within a few seconds, the thermistor or board may be the issue. If you hear clicking but no flame ignites, move to step 2.

Verify LP supply. Confirm the tank has fuel and the valve is fully open. Light a stovetop burner to verify gas is flowing through the system. If the stove works fine, gas supply is likely not the problem.

Inspect the burner and flue. Remove the exterior lower access panel. Look into the burner tube for rust flakes, spider webs, mud dauber nests, or soot. Use compressed air and a fine wire brush to clean the jet orifice and burner tube. Check the flue above for blockages — drop a flue brush or straightened coat hanger gently down from the roof vent cap.

Check the electrode. The igniter tip should be positioned approximately 1/8 inch from the burner head with no cracks in the porcelain insulator. Clean carbon deposits off the tip with fine sandpaper. Inspect the wire for chafing or breaks.

Test the thermistor. Locate the thermistor clipped to the cooling fins at the rear. Check for corrosion or a loose connection. With a multimeter, measure resistance — it should read roughly 5–10 kΩ at room temperature (varies by model). An open or shorted reading means replacement is needed.

Evaluate the control board. If the burner lights, the thermistor reads correctly, and the board still flashes the check light after a reset, the board itself may be faulty. Look for burnt components, swollen capacitors, or scorched traces on the board.

When to Call a Technician

Call a certified RV technician if:

You smell propane and cannot identify the source
The burner lights but produces a yellow or sooty flame (combustion issue)
The control board needs replacement and you are not comfortable working with 12V DC wiring and LP gas connections
The fridge cycles through resets without improvement — this may indicate a sealed cooling unit failure (ammonia leak), which requires full unit replacement

Dometic Fridge Flashing Check Light

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