Valeo CITYSPHERE, Инструкция по установке и обслуживанию

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Rooftop Air Conditioning System Citysphere
Page 73
Low pressure gauge reading too low
– Intake or delivery line restricted, e.g. by kinks
– Expansion valve defective
– Not enough refrigerant
– Evaporator air flow restricted
– Collector/drier clogged
6.7. Repairs
IMPORTANT
Under no circumstances may refrigerant be discharged into the atmosphere.
NOTE
The safety precautions and regulations contained in chapter 1.3 and 6.2
must be observed.
Only genuine spare parts may be used for repairs and the original condition
must be restored.
a) Always use genuine spare parts or standard parts for repairs.
b) The system's original condition must always be restored when performing repairs.
c) Before opening / disassembling components in the refrigerant circuit, the refrigerant must be
drained into the recycling station provided and disposed of properly or reused.
d) After completing repairs on the refrigerant circuit, the system must be
– evacuated in accordance with the operating instructions of the recycling station
– filled with refrigerant on the high pressure side, with the system at rest
6.8. Post-repair procedures and testing
6.8.1. Check refrigerant pressures
General
As a rule, every air conditioning system filled with refrigerant is a pressurized system. The pressure is the
same throughout the system circuit and depends on ambient temperature.
During operation of the system, the working pressure on the intake side differs from that on the delivery side
of the compressor. The pressures differ and are influenced by the compressor operating speed, the
temperature inside the vehicle, the outside air temperature and relative humidity. Abnormal working
pressures indicate that there is a fault in the system.
The working pressure should be tested with an on-board power supply of 24-26 V and at air temperatures
between 17°C and max. 35°C. The system must be operated in the test mode . The hood must be fitted
for the pressure test since the air pressure of the heat exchangers has a decisive influence on whether or
not the operating pressure is reached.