Service Manual

SiUS181631EA Troubleshooting for Outdoor Unit
Troubleshooting 229
7.3 Actuation of Low Pressure Sensor
Error Code
E4
Method of Error
Detection
Detection by the pressure value with the low pressure sensor
Error Decision
Conditions
When the low pressure is dropped under specific pressure
Operating pressure: 0.07 MPa (23 ftAq)
Supposed
Causes
Abnormal drop of low pressure (Lower than 0.07 MPa (23 ftAq))
Defective low pressure sensor
Defective outdoor unit PCB
Stop valve not opened