Friedrich Q Series Service & Parts Manual page 65

AIR CONDITIONERS: TROUBLE SHOOTING TIPS
REFRIGERANT SYSTEM DIAGNOSIS – COOLING CYCLE
LOW SUCTION PRESSURE HIGH SUCTION PRESSURE LOW HEAD PRESSURE HIGH HEAD PRESSURE
Low Load Condi�ons High Load Conditions
High Load Conditions
Low Load Condi�ons
Low Air Flow Across High Air Flow Across Refrigerant System Low Airflow Across
Indoor Coil
Indoor Coil Restriction Outdoor Coil
Refrigerant System Reversing Valve not Reversing Valve not
Overcharged
Restriction Fully Seated Fully Seated
Noncondensables (air)
Undercharged Overcharged Undercharged System
in System
Moisture in System Defective Compressor Defective Compressor
Figure 712 (Trouble Shooting Tips)
65