Technical data

21
TROUBLESHOOTING CHART
Below we list a series of possible faults, along with the probable causes and suggested solutions. In the event of a unit
malfunction, it is advisable to disconnect the power supply and ascertain the cause.
SYMPTOMS CAUSE REMEDY
Unit does not start
Unit operates continually or starts and
stops frequently
Compressor continually cuts out at low
pressure or via the DGT (electro-
mechanical version or low-temperature
option)
Compressor continually cuts out at high
pressure
Noises in the system
Compressor loses oil
Water losses
Frosted or sweating suction line
Hot liquid line
Frosted liquid line
Compressor will not unload
Compressor will not load
Connect power supply
Close switch
Check voltage and remedy the deficiency
Reset
Replace contactor
Check windings (grounded or short circuit), replace
compressor
Check connections
Check the circulating pump, check the controller
Replace contactor
Check valves, replace compressor
Check and add the necessary charge
Check the capillary tube, if necessary replace the
pressure switch
Add the necessary refrigerant charge
Check water pump
Clean or replace
Replace filter
Replace pressure switch
Check the fan(s) and the contactor(s)
Clean the condenser
Check valve plate, change if necessary
Install correctly
Support piping, check supports and tightness
Repair leak
Check and tighten if necessary
Adjust expansion valve
Repair leak and recharge
Remove restriction or replace filter-drier
Replace coil
Clean or replace
Wire correctly
Replace
Replace
Wire correctly
Clean
Lack of power supply
Main switch open
Low line voltage
A protection device has tripped
Contactor stuck open
Seized compressor or short circuit
Loose electrical connections
Flow switch open
Defective compressor contactor
Defective compressor
Refrigerant losses
Low pressure switch defective
Refrigerant losses
Low water flow in the evaporator
Blocked expansion valve
Blocked filter drier
Defective high pressure switch
Defective fan(s)
Low water flow in the condenser
Noisy compressor
Badly fitting panels
Piping vibrations
Leak in the system
Defective inlet or outlet connections
Expansion valve admitting excess refrigerant
Shortage of refrigerant due to leak
Restricted filter-drier
Burned out coil
Leaky bypass piston
Miswired solenoid
Weak bypass piston spring
Damaged bypass piston
Miswired solenoid
Plugged bypass port strainer (high side)