Error Code: PC 46 – Compressor Speed Out of Control

Error Code: PC 46 – Compressor Speed Out of Control

What this means:
The system has detected that the compressor is running at an abnormal speed — either much faster or slower than expected. This can be caused by power supply issues, incorrect control signals, or hardware problems with the compressor or outdoor PCB.

Try this first (quick reset):

1. Turn off power to the unit completely.

2. Wait 2 full minutes.

3. Turn it back on and check the display.

• If the error clears — it may have been a temporary control glitch.

• If the error returns — continue with the steps below.

Next steps (for technicians):

1. Check power supply voltage:

   • Ensure the input voltage (between L and N) is within 220V–400V range.

   • Measure the DC bus voltage (between P and N) — should be around 310V, 340V, or 380V in standby.

   • Reconnect or correct power wiring if voltage is abnormal.

2. Inspect the reactor and inductance wiring:

   • Make sure all wiring is properly connected.

   • If not → reconnect or replace.

3. Test reactor and inductance functionality:

   • If either is faulty → replace the reactor.

4. Check ventilation and outdoor temperature:

   • If ambient temperature exceeds 50°C → allow cooling.

   • Confirm that the outdoor fan is running and the heat exchanger is clean.

5. Inspect the refrigerant system:

   • If system pressure is too high due to overcharge → safely recover excess refrigerant.

   • If pressure is normal but compressor speed remains erratic → replace the outdoor PCB.

What you might need:

• Outdoor PCB

• Reactor

• Connection wires

• Compressor (if found faulty)

• Refrigerant recovery tools

Helpful tip:
Compressor speed issues are often tied to unstable voltage or blocked airflow. Always rule out power and ventilation problems before replacing control boards.

Click here to view the detailed guide.TS08-S