Er 11

Dometic Refrigerator: “Er 11”

warning RV refrigerator error codes

Safety These are gas-absorption fridges. Before working at the rear of the unit, turn it off and isolate both 120V AC and the 12V DC supply; the defrost heater and AC heater run on line voltage. If you ever smell propane/gas near the fridge or its vent, stop, shut off the gas supply, ventilate, and do not switch anything electrical on or off until it clears.

What it means

The control board has detected an open circuit in the freezer-plate defrost heater. In other words, the board can no longer 'see' the freezer evaporator/plate defrost heating element, so it flags it as faulty. The code flashes on the LED panel alternating with the 'CALL' message.

Most likely causes

Blown control-board fuse F4 (7.5 A) that feeds the freezer-plate defrost heater most likely
Loose or disconnected harness at terminal J5 (heater feed) on the lower control board common
Loose ground cable to the heating element at terminal J1 on the lower control board common
Loose/incorrect connections in the inter-connection box inside the freezer compartment common
Blown internal overheat (thermal) fuse inside the defrost heating element (element must be replaced) less common
Open/broken defrost heating element itself (element must be replaced) less common

Safe checks you can do yourself

Confirm the model is a 2-way/electric absorption fridge that uses the Er-code system (e.g. NDA1402/NDE1402 and similar); read the exact code off the LED panel.
With the fridge OFF and 120V unplugged and 12V disconnected, visually inspect the wiring harness and connectors at the back of the fridge and at the freezer inter-connection box for loose, corroded, or unseated plugs.
Check that the 12V supply to the fridge is healthy (at least ~10.5–12V); weak DC can cause defrost/heater faults and related warnings.
After reseating connectors, restore power and see whether the code clears (some faults only re-test at power-on, so an OFF/ON cycle is needed).

How to reset / clear Er 11

Turn the refrigerator OFF at the control panel.
Disconnect 120V AC (unplug) and the 12V DC supply (battery disconnect or pull the fridge fuse) for several minutes.
Reconnect power and turn the fridge back ON; the board re-runs its self-test.
If the open-circuit fault is gone, the code will not reappear; if it returns, the heater circuit or board needs service.

When to call a technician

If the F4 fuse is intact and all connectors are clean and tight but Er 11 returns, the defrost heating element (possibly with a blown internal thermal fuse) or the lower control board is defective — have a qualified RV refrigeration tech test and replace it.

Accuracy notes

Confirmed from the official Dometic NDA1402/NDE1402 diagnostic service manual. Important: Dometic reuses two-digit numbers across different control generations, so on newer platforms (RM10, RMD, RUA/RUC, etc.) a code '11' may NOT mean the freezer-plate defrost heater. Verify against the manual for your exact model and serial. This record applies to the 'Er'-code generation with separate freezer/fresh-food defrost heaters and fans.

Applies to

NDA1402 · NDE1402 · NEA1402 · other Dometic 2-way/electric absorption models that display 'Er' codes with a freezer-plate defrost heater

FAQ

What does Dometic Refrigerator code "Er 11" mean?

How do I reset Dometic Refrigerator Er 11?

Turn the refrigerator OFF at the control panel. Disconnect 120V AC (unplug) and the 12V DC supply (battery disconnect or pull the fridge fuse) for several minutes. Reconnect power and turn the fridge back ON; the board re-runs its self-test. If the open-circuit fault is gone, the code will not reappear; if it returns, the heater circuit or board needs service.

What is the most common cause of Er 11 on a Dometic Refrigerator?

The most likely cause is blown control-board fuse f4 (7.5 a) that feeds the freezer-plate defrost heater.

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Sources

Diagnostic Service Manual — Dometic NDA1402 & NDE1402 Refrigerators — Section 11.2 Error Codes, p. 34 ("Er 11": open circuit to the freezer-plate defrost heater; fuse F4, terminals J5/J1) (Dometic, LLC)

● Checked against 1 manufacturer document · Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual. How we verify