jcb JS 200 Series, Руководство по обслуживанию

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12 - 5
Fault Finding
Procedures that require charging or discharging the system are not given in this manual as they require special equipment that
is usually held only by trained refrigeration engineers. Fault indications are given in the table below.
The system will not function in very low ambient temperatures, therefore tests should be carried out in a warm environment.
It is recommended that, to locate faults on the system accurately and quickly, an electronic leak detector and a refrigerant
pressure gauge should be used. However, leaks can be detected on the system by using soapy water applied to the suspected
leak area and system pressure can be assessed by the state of refrigerant passing through the receiver drier sight glass.
Following sections of the manual deal with the major components of the air conditioning system and give further fault finding and
maintenance information.
General Fault Indications
There are several indications that may help to determine the fault area on a system not working efficiently:
a) Poor performance Low system pressure - Evacuate and recharge system.
Condenser coil air flow restricted - Remove debris from around coil using
compressed air or low pressure water.
Air filters blocked Clean with detergent and water.
Compressor drive belt too slack Adjust to correct tension.
b) Warm or slightly cool air Expansion valve stuck open or closed - Renew expansion valve.
emitted from unit
c) Blower does not operate Fuse blown Replace fuse (20A) and retest.
Circuit fault Fault find and repair.
d) Compressor clutch Condenser coil blockage - Remove debris from around coil/renew condenser.
continually cuts out Overcharging of refrigerant system- Evacuate and recharge system.
Blocked expansion valve/condenser - Clear blocked component .
Sight Glass Indications
An approximate indication of the condition of the refrigerant can be seen through the receiver/drier sight glass when the
compressor is running. Refer also to
Checking Refrigerant Charge Level
, on page 12-8.
Clear - No fault indicated unless the system is unable to provide cool air. The indication then is that
the system is completely discharged of refrigerant.
Foam or bubbles - Refrigerant low and in need of charging.
Clouded - Desiccant breakdown in the receiver-drier.
Note : Sight glass indications cannot always give a positive identification of a problem. Further diagnosis, preferably by a
refrigeration engineer using pressure gauges, is advisable before reaching a definite conclusion.
Section B
Body & Framework
9803/6400
Section B
12 - 5
Issue 1
Air Conditioning
S201520C
S201520A
S201520B