T086_F - Suction Pressure Sensor Failure
Status
This is a critical fault for furnaces that use electronic expansion valve. Suction pressure is used in the algorithm that drives the electronic expansion valve.
Description
This fault indicates the suction pressure sensor is either open or shorted, or has been removed after being installed.
Expected Operation
The fault "T086_F Suction Pressure Sensor Failure" will be declared. Cooling operation will struggle due to this fault.
Cause
1. Suction pressure sensor was installed and removed without cycling power.
2. Suction pressure sensor or wiring has failed.
3. Bad furnace control board.
Solution
1. If no suction pressure sensor was ever installed, cycle power to remove fault and check control for indication of condensation that may have temporarily tricked it into thinking one had been installed.
2. Replace suction pressure sensor.
3. Replace furnace control board.
