Friedrich Kuhl KCS12B10A Service Manual page 60

HEAT PUMP ROOM AIR CONDITIONERS: TROUBLE SHOOTING TIPS
LOW SUCTION PRESSURE
Low Airflow Across
Outdoor Coil
Refrigerant System
Restriction
Undercharged
Moisture in System
FAULT
SYSTEM COOLS WHEN
HEATING IS DESIRED
60
TROUBLESHOOTING
REFRIGERANT SYSTEM DIAGNOSIS - HEATING CYCLE
HIGH SUCTION PRESSURE
Outdoor Ambient Too
High for Operation in
Heating
Reversing Valve not
Fully Seated
Overcharged
Defective Compressor
ELECTRICAL TROUBLESHOOTING CHART - HEAT PUMP
Is Selector Switch
Set For Heat?
Replace The
Solenoid
Figure 604 (Trouble Shooting Tips)
LOW HEAD PRESSURE
Refrigerant System
Restriction
Reversing Valve not
Fully Seated
Undercharged
Noncondensables (air)
in System
YES
Is Line Voltage
Present At The YES
Solenoid?
Is The Solenoid
NO
Replace The
Reversing Valve
HIGH HEAD PRESSURE
Outdoor Ambient Too
High For Operation In
Heating
Low Airflow Across
Indoor Coil
Overcharged
Noncondensables (air)
in System
YES
Good?
Is The Reversing
Valve Stuck?
YES