Panasonic 140 Installation And Maintenance Manual page 47

Problem Probable cause
Incorrect operation of the high pressure pressostat.
Circuit stoppage
Outlet valve partially closed.
further to the
high pressure
thermostat being
Non-condensable particles in the circuit.
activated.
Condenser fan(s) not operating.
Liquid line too
Insuffi cient refrigerant fl uid charge.
hot
Liquid line valve partially closed.
Liquid line frozen
Clogged dehumidifi cation fi lter.
Electrical circuit problems.
Fans do not
operate.
Internal circuit thermal cut-out activated.
Compressor operating fault
Reduced output
Dirt in the evaporator water circuit.
in both Heating
and Cooling
Condenser battery blocked.
mode
Insuffi cient refrigerant fl uid charge.
No power supply.
Evaporator
heater is not
operating.
Heater circuit open
Incorrect thermostat setting.
No/ little control
Incorrect temperature differential between
over water
evaporator inlet and outlet.
temperature.
Electronic control system malfunction.
Air in the circuit
Insuffi cient water
circulation.
Deposits or impurities in the evaporator.
Water circulation fault
Unit not
operating, no Flow controller inoperable.
alarm activation
Differential pressostat inoperable.
Solution
Check the operation of the pressostat. Replace it if
required.
Open the valve. Replace it if required.
Bleed the circuit
Check the wiring and the motors. Repair and
replace if required.
Locate and eliminate the causes of charge losses
and top up the refrigerant fl uid charge.
Check all valves are opening.
Replace the fi lter cartridge.
Check the connections.
Contact an approved Service Centre.
Contact an approved Service Centre.
Chemically clean the evaporator water circuit.
Clean the condenser battery.
Top up the refrigerant fl uid charge.
Check the main fuse and the auxiliary fuses.
Check the heater and replace if required.
Check the temperature setting on the control panel.
Check the water fl ow and the quantity of liquid in
the water circuit.
Contact an approved Service Centre.
Bleed the air via the safety valve.
Wash out the evaporator by back-fl ushing.
Check the pump.
Check the fl ow controller.
Check the differential pressostat.
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