Valeo CITYSPHERE, Installation And Service Instructions Manual

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Rooftop Air Conditioning System Citysphere
Page 72
6.6. Troubleshooting
6.6.1. General
a) A systematic approach is advisable for troubleshooting. Appropriate action must be undertaken as
described below for faults of a general nature or when normal conditions are not obtained during
the pressure test.
b) Certain faults can only be located and remedied by skilled personnel using special tools.
6.6.2. Cause of faults in the electrical system
The individual circuits must be systematically checked with the aid of the circuit diagram (see Fig. 3.2) and
the fault localized. Above all plug connections, switches, relays, etc., should be checked for continuity.
The following possibilities must always be checked and excluded as a possible cause of the malfunction:
– Defective fuses
– Corrosion of plug contacts
– Loose contact in plug connectors
– Wrong crimping on connector
– Corrosion on wiring and fuses
– Corrosion on battery poles
6.6.3. Cause of faults in the air conditioning system
– defective evaporator or condenser fan
– contaminated or clogged air filter, soiled evaporator or condenser fins
– shortage of refrigerant in the system
If the system is deactivated continuously, we recommend that it be checked by an authorized workshop.
6.6.4. Dealing with problems in the refrigerant circuit
If faults develop in the refrigerant circuit, the system must be tested and repaired by an authorized specialist
repair shop according to the rules. Refrigerant must never be discharged into the atmosphere.
6.6.5. Cause of faults making it impossible to reach the required states during pressure tests
Divergences from the required state during pressure tests (chapter 6.8) may be due to the following causes.
These causes must be checked, the trouble located and defective components repaired or replaced.
High pressure gauge reading too high
– Condenser air flow restricted
– Too much refrigerant
High pressure gauge reading too low
– Not enough refrigerant (check sight glass)
– Compressor speed too low. (System in standard operation, maximum number of revs can be forced in
test mode (5.5.1))
– Compressor defective
Low pressure gauge reading too high
– Expansion valve defective
– Compressor speed too low
– Compressor defective