CC 145
23
AC does not cool down and
the compressor remains on
Lack of refrigerant
Check for leakage, fill to correct amount
Air or other gas in the system
Draw a vacuum (min. 3 hours below 10 mbar) replace filter drier, fill to correct
amount
Dirty or defective expansion valve
Replace the valve
Dirty evaporator coil
Clean the coil
Air filter dirty
Clean or replace filter
It cools down too much and
the compressor does not
turn off
Incorrect temperature selection
Adjust the temperature on the control panel
Temperature sensor badly placed
Place the sensor appropriately
High discharge pressure
Excess refrigerant in the system
Drain and capture refrigerant, fill to correct amount
Refrigerant flow obstructed
Check for restriction (compressor valve partially closed, expansion valve blocked,
filter drier blocked, etc.)
Condenser motor is stopped
Refer to symptom "Condenser motor is stopped“
Dirty condenser coil
Clean and wash
Low suction pressure
Lack of refrigerant
Check for leakage, fill to correct amount
Air return temperature is too low
Place the temperature sensor at the most appropriate position
Dirty or defective expansion valve
Replace the valve
Evaporator motor is stopped
Replace motor
Restriction in the system
Eliminate
Loaded air filter
Clean or replace filter
Dirty evaporator coil
Clean coil
Symptoms
Probable cause
Solution
Fig. 6 Failure Diagnosis Table
