Air conditioning loses a little gas every year, so most systems need a re-gas every two years or so. If the air is cool but not cold, low gas is the usual culprit.
If it blows warm, smells musty, or the fan is noisy, there may be a leak, a blocked pollen filter or a failed compressor. A re-gas alone will not fix a leak.
We test the system before topping it up — the process is explained on our air conditioning page.
Running the air con for ten minutes a week, even in winter, keeps the seals healthy.