Störungscode H11_H12_H21_H22_ECOi_MF1

H11: Constant speed compressor 2 overcurrent alarm
H12: Constant speed compressor 2 lock current alarm
H21: Constant speed compressor 3 overcurrent alarm
H22: Constant speed compressor 3 lock current alarm

Hx1: During operation, the compressor current value exceeded 20 A for 30 seconds or longer. However this alarm is not detected for 4 seconds after the compressor starts.

Hx2: During operation, the compressor current value exceeded 29 A for 4 seconds or longer. However this alarm is not detected for 2 seconds after the compressor starts.

1. Compressor failure (locked or partially locked)
2. CT circuit failure (including cut wiring)
3. Missing power phase
4. Low power voltage
5. PCB failure

1. Compressor failure (partially locked)

Trouble: Current value during operation greatly exceeds the value shown above.

Check: When the current for each phase is measured with a clamp meter or similar instrument, check that the current value for all phases is not high. If MG was forced ON (use caution), check that compressor noise will not occur or the compressor will not run with a groaning sound.

2. CT circuit failure, PCB failure

Trouble:
Check:
• Check for poor connector contact.
• Check the continuity of the CT circuit.
• Install a normal CT in place of this CT and check. If current is detected, then the PCB   can be judged OK.
  → CT circuit failure
• Check that current is flowing in the phase where the CT circuit is connected.
  → Check voltage and current.

3. Missing power phase

Trouble: This alarm primarily occurs when the T-phase is missing. When the R-phase or S-phase is missing, CT trouble or PCB continuity trouble occur. However this may not be true in the case of a missing phase caused by magnet SW trouble.

Check: There is the possiblility of a magnet SW failure. Therefore, check the phase voltage at a location that is as close to the compressor as possible.

4. Low power voltage

Trouble: In most cases, this occurs when another constant-speed compressor (including compressors in other units) or other device starts. It also occurs when the power wiring is extremely long.

Check: Check the voltage between each of the phases. However if this trouble occurs when other devices or compressors start, then an oscilloscope is required.

5. PCB failure

Trouble:
Check: Check that the current value measured with the clamp meter is not lower than the value measured with the PC or remote controller.

6. If the cause is still unknown after checking the above, then it is possible that noise is the cause of the trouble. It is necessary to connect a PC or other instrument.

1. Replace the compressor.
2. Replace the CT circuit.
3. Repair the power circuit.
4. Adjust the primary-side power. Repair the power wiring.
5. Replace the outdoor unit PCB.
6. Correct the trouble.
   * In the case of a compressor failure, it is likely that steps must be taken to correct the cause of the compressor failure (such as liquid back-up) in order to prevent recurrence. Be sure to check that there is no cause which may resuit in compressor locking.