Mitsubishi Heat Pump Error Code P1: How to Fix It

Q: What causes Mitsubishi heat pump error code P1?

Error code P1 is caused by a faulty indoor air temperature sensor (TH1 thermistor). This can result from sensor age, electrical damage, poor connections, or exposure to moisture or debris.

Q: Can I continue using my heat pump with P1 error?

It's not recommended to continue operation with P1 error. The system cannot properly regulate temperature without the sensor, which may lead to inefficient operation, comfort issues, or potential damage to other components.

Q: How much does it cost to replace a heat pump temperature sensor?

The sensor itself typically costs $20-50, while professional installation ranges from $150-300 depending on your location and the complexity of access to the sensor.

Q: How do I prevent future P1 errors on my Mitsubishi heat pump?

Regular maintenance including cleaning air filters, keeping the indoor unit free of dust and debris, and annual professional service can help prevent sensor failures and extend component life.

Q: Will replacing the TH1 sensor fix P1 error permanently?

Yes, if the sensor is the root cause. However, if wiring issues or other system problems caused the sensor failure, those underlying issues must also be addressed to prevent recurrence.

Abstract

Mitsubishi heat pump error code P1 indicates a malfunction with the indoor air temperature sensor (TH1 thermistor). This sensor monitors room temperature to help the system maintain your desired comfort level. When it fails, the heat pump cannot properly regulate temperature and may shut down to prevent damage.