Fault Finding - jcb JS300 Service Manual

Preliminary Checks
Before any checks are carried out on the refrigerant circuit
the following checks should be made:
1 Check the compressor drive belt is serviceable and
correctly tensioned.
2 Check the condenser and engine radiator are not
blocked by debris, clean with compressed air or water
if necessary.
3 Check that the condenser fins are not flattened or
damaged, the fins must allow air to pass freely.
4 Check the cab fresh air inlet filter for blockage.
5 Check that, with the ignition switch on (engine not
running), the blower operates over whole speed
range.
6 Check that, with the ignition switch on (engine not
running), the blower and air conditioning switched on,
the compressor clutch engages.
Charge level:
Note: It is not possible to check refrigerant charge level
with R134a systems using the receiver drier sightglass.
Any bubbles seen at the sight glass on the receiver drier
may be bubbles of oil and are perfectly normal.
– Gas -1400g R134A +/- 10g
– Oil - 150g +/- 5g PAG (PolyAlkylene Gycol) oil to ISO
100

Fault finding:

Important: Refer to appropriate remove and replace
procedures before working on any system component
B-16
Section B - Body and Framework
Heater/Air Conditioning SYSTEM
Fault Finding
9813/5100-1
Fault Finding
B-16