Air-con check in spring — why now and not in July

Why air-con loses a little every year

An air-con system is never completely sealed. A small amount of refrigerant escapes each year through hoses, connections and the compressor seal; that is normal. Once the quantity drops below a certain point the system switches the compressor off to protect it — and the air-con blows lukewarm.

Important: topping up is not a repair if there is a leak. So we first measure how much is in the system; with a clear shortfall we look for the leak rather than adding the same amount every spring. The full list of causes is in air-con blowing warm air.

What we check in spring

• Quantity and pressure of the refrigerant, and whether the compressor engages.
• Leaks at connections, condenser and compressor seal.
• The condenser — it sits at the front and collects insects, leaves and dirt. Fouled means less cooling and a higher load on the system.
• Cabin filter, often clogged after winter. This is also the cheapest improvement to airflow.
• Evaporator and smell. If it smells musty on switching on, there is mould on the evaporator — a clean solves that.
• Condensate drain. If it blocks, condensation runs into the interior; see damp in the car.

What you can check yourself

• Set the air-con to its coldest setting and listen for a click when it engages.
• Feel whether all vents blow equally cold.
• Look for a puddle of water under the car after use — that is condensation and entirely normal.
• If it smells musty, don't wait: mould does not reduce by itself.

Use it in winter too

The compressor is lubricated by oil circulating with the refrigerant. If the air-con is unused for months, seals dry out and the system leaks faster. Switching it on briefly once a month is the cheapest prevention there is — more in air-con servicing in winter too.

Unsure whether to refill or repair? Start at the air conditioning service in Tilburg.