Error 400 — Overheat caused by contact failure on IPM of Inverter PBA2

What does 400 mean?

Overheating has been detected on the Inverter Power Module (IPM) of Inverter PBA2, most likely caused by a poor electrical contact. This is a safety shutdown to prevent damage to the inverter.

• Loose electrical connections to the IPM
• Faulty IPM (Inverter Power Module)
• Inadequate cooling or airflow around the IPM
• Dirt or corrosion on contact points

Click steps to track your progress.

1. 1

   Immediately turn off the outdoor unit's power at the circuit breaker.

2. 2

   Allow the unit to cool down completely for at least 30 minutes.

3. 3

   CAUTION: This requires a professional. Inspect the connections to the Inverter PBA2's IPM for any signs of loose contacts or corrosion.

4. 4

   Ensure proper ventilation around the outdoor unit and that airflow isn't restricted.

5. 5

   If the error persists, the IPM or Inverter PBA2 may need replacement by a qualified HVAC technician.