Mitsubishi Electric UE error code

What it means

UE means the outdoor unit detected a stop-valve or closed-valve condition. That can prevent refrigerant from moving correctly and can damage the compressor if the system keeps trying to run. This is especially important after installation, service, or a recent move of the outdoor unit. Manual trigger: The outdoor unit detects a stop-valve or closed-valve condition.

Urgency

Likely causes

1. Actual refrigerant leak at a flare joint, coil, line set, or service connection
2. Low refrigerant charge or charge loss after installation or service
3. Refrigerant sensor, T1/T2, or related control input reading abnormally
4. Indoor or outdoor board fault only after the leak and sensor checks pass

Homeowner fix

Turn the system off and do not keep testing modes or resets. Expected result: the compressor and electronics are protected until the installation or equipment mismatch is corrected.

When to call a pro

Call the installing contractor, Mitsubishi dealer, or licensed HVAC technician before running it again. Tell them the exact Mitsubishi stop-use code and whether installation or service happened recently.

Repair vs replace

This is usually an installation or equipment-selection correction, not normal wear. Replacement may be required for the mismatched component, but not automatically for the entire system.

• Mitsubishi Electric M-Series GX 9,000 BTU R-454B 208/230V (MSZ-GX09NL / MUZ-GX09NL)

  M-Series GX

• Mitsubishi Electric M-Series GX Hyper-Heat 9,000 BTU R-454B 208/230V (MSZ-GX09NL / MUZ-GX09NLHZ)

  M-Series GX

• Mitsubishi Electric M-Series GX 12,000 BTU R-454B 208/230V (MSZ-GX12NL / MUZ-GX12NL)

  M-Series GX

• Mitsubishi Electric M-Series GX Hyper-Heat 12,000 BTU R-454B 208/230V (MSZ-GX12NL / MUZ-GX12NLHZ)

  M-Series GX

Parts for this line

The parts catalog for Mitsubishi Electric M-Series GX lists 6 sourced replacement parts for this product line.

For your technician

Technician note: verify model voltage, branch-circuit voltage, stop-valve position, refrigerant type, and approved indoor/outdoor combination before operation. Page context: Mitsubishi Electric maps this display to the M-Series GX line; source: Mitsubishi Electric MSZ-GX/MUZ-GX R454B service manuals; display convention: match the letter U and letter E marker exactly before comparing neighboring codes.

Which systems show it

• Mitsubishi Electric M-Series R454B wall-mount outdoor units covered by MUZ-GX OBH951C and cross-checked against MUZ-FX OBH946C and MUZ-WX OBH955A.

Related troubleshooting

Use the symptom guide alongside the exact display code if the unit is flashing, cycling, or showing comfort symptoms.

Reset note

After the documented cause is corrected, operate the unit and confirm the failure-mode recall/error-code display returns to 00.

Manual trigger

The outdoor unit detects a stop-valve or closed-valve condition.

Related codes

Source

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