Why Your Air Conditioning Stops Cooling.

Air conditioning rarely dies all at once. It fades over a fortnight, and by the time it is blowing warm on the hottest day of the year, the cause has usually been there for weeks.

The filter, which is nearly always the filter

Every indoor unit has a mesh filter behind the front cover. It clogs with dust and the unit starves for air. Cooling drops, running costs rise, and eventually the coil ices over because there is not enough warm air moving across it.

Take the cover off, slide the filter out, rinse it, let it dry completely, put it back. Once a month in summer. This is the one job we would rather you did than paid us for.

A coil that has iced up

If you can see frost on the pipework or the indoor fins, switch the unit off and leave it off for a couple of hours. Running it while it is frozen is how compressors die.

Ice is a symptom, not a fault. It means airflow or refrigerant is low. Once it has thawed, if it ices again within a day, stop and call.

Refrigerant that has leaked

A sealed system should never need topping up. If it does, it has a leak, and adding gas without finding the leak is money poured into the garden. We pressure test, find it, fix it, then recharge by weight.

Handling refrigerant is regulated work. It is not a job for a general handyman.

An outdoor unit that cannot breathe

Cut the shrubs back to half a metre on every side, clear the leaves out of the base, and check nothing has been stacked against it over winter. The unit has to dump heat somewhere, and a fence panel six inches away means it dumps it straight back into itself.

When to call

Warm air after a clean filter and a thaw. Ice returning within a day. Water dripping from the indoor unit onto the floor. A burning smell, or a breaker that trips when it starts. Any of those, leave it off and ring us on 0800 019 4417.