H2
Day & Night
Defrost Termination / Outdoor Coil Sensor Error (Heat Pump)
H2 code, auxiliary heat may run excessively, high electric bills
Advertisements
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Advertisements
Possible Causes
Defrost sensor misreading coil temperature, Sensor not properly attached to coil, Faulty defrost control logic, Wiring issues between sensor and board
How to Fix / Troubleshooting
Safety first: Disconnect power at the outdoor disconnect before working on the heat pump.
- Step 1 – Inspect defrost sensor: Confirm the sensor is firmly clipped to the correct location on the outdoor coil per Day & Night service manual.
- Step 2 – Check for moisture intrusion: Ensure the sensor and its connection are dry and protected from direct water spray.
- Step 3 – Wiring continuity: Check for damaged or spliced wires between the sensor and control board.
- Step 4 – Replace sensor if suspect: If the sensor appears damaged or tests out of spec, replace it.
- Professional evaluation: If H2 persists, the defrost control algorithm on the board may be faulty and require board replacement.
Advertisements
Repair Difficulty
Hard
4/5
Required Part
Defrost Sensor (Outdoor Coil)
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements