How a vehicle air conditioner works, why diagnostics are needed, which equipment is used and the main faults diagnostics can reveal.
Vehicle air conditioners work under harsh conditions such as temperature swings, damp, dust and dirt, so demand for A/C diagnostics is high. Refrigerant is compressed in a sealed circuit, cooled in the condenser, passed through the receiver-drier, reduced in pressure at the expansion valve and returned via the evaporator to the compressor. Any loss of tightness can cause serious damage.
That is why work on the A/C should only follow professional diagnostics. The MS111 test bench handles piston, axial piston, rotary and scroll compressors. Problems diagnostics can reveal include:
- Leaks and mechanical seizure of the compressor
- Electrical faults and blockages in the circuit
- Excess pressure, faulty expansion valves, a dirty cabin filter
Delayed repair can lead to complete A/C failure.