Why does the air con cools on and off intermittently?
Essentially, this is due to a faulty air con system. There are a few possible causes for this:
1) The condenser coil is filthy
When operating, an aircon emits heat. When the condenser cooling coil is dirty and clogged, the heat is unable to dissipate out effectively, hence causing the compressor to overheat. In response, the thermal switch in the aircon compressor will automatically cut out the operation. When the air con compressor has cooled, it will then turn on automatically again.
2) A faulty thermal switch
However, if the condenser coil has been cleaned, and the on-off problem persists, then the thermal switch may be problematic. An air con professional will then have it repaired or if needed, replaced.
3) Insufficient refrigerant in the air con
If there are insufficient refrigerant in the system, the symptom will be very much similar to a filthy condenser coil described above. The solution will then be to top up additional refrigerant and do a visul check for any possible leakage in the piping joint. A qualified air con professional will be needed to perform this task correctly.