With an improvement of the weather, I always see an increase in the number of drivers who suddenly realised that the air conditioning isn’t working, or isn’t working well. Many owners don’t realise that it is recommended that at least once every couple of weeks, even during the winter, that the air conditioning should be bought into play, to ensure everything keeps turning and the lubrication in the system is nicely circulated.

This is not normally a problem, as most heating and ventilation systems will automatically switch on the A/C, when the demist position is selected. This is because the air conditioning has a drying effect on the air, which helps clear the misted screen.

The owner of this 2009 Nissan Qashqai 1.5 dCi, knew that the air conditioning had not been operating since the end of last summer, but was under the impression that he could just wait until it was needed, and then have the system pressurised again.

Not realising that it is not good to leave the system in an uncharged condition, when I went to re-charge the system, I first conducted a Nitrogen pressure check, and I discovered a leak. The A/C compressor had a failed bearing, and this had put pressure on the pulley clutch. A new pump was needed before I could go any further.

Once the new pump was fitted, the pressure check was repeated and this time the pressure held, meaning that the system could be charged (and so could the customer!).

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