15:15 06-06-2026

Car AC in Summer: The Button That Quietly Damages Your Health

Doctors warn that blasting the AC to 18°C after parking in the sun is the fastest way to a sore throat. The right approach is gentler than it sounds.

In summer, drivers slide into a sun-baked cabin and immediately reach for the climate control, dialling it down to 18 degrees. The logic seems obvious: the lower the number, the faster the relief. But doctors warn that a sharp temperature jump hits the throat, airways and overall wellbeing.

The real benchmark isn’t the lowest possible setting — it’s the gap between outside and the cabin. Experts recommend keeping it within roughly 6 degrees. If it’s 30 outside, aim for around 24 inside rather than turning the car into a fridge. Otherwise the body takes a thermal shock: it goes from heat straight into a stream of cold air, then back out into the heat again. The result is a sore throat, runny nose, hoarseness and that drained feeling after the drive.

There’s another unpleasant side effect: an air conditioner doesn’t just cool the air, it dries it out. On a long trip that brings on a scratchy throat, dry mucous membranes, burning eyes and the sensation of grit under the eyelids. It’s especially rough on contact lens wearers and anyone spending hours behind the wheel.

A dirty system is more dangerous than the cold itself. A damp evaporator, the air ducts and an old cabin filter are happy breeding grounds for fungi, mould and bacteria. Among the potential threats, experts mention Legionella pneumophila: the infection looks like flu at first but in severe cases can develop into pneumonia. Regular AC maintenance isn’t just about comfort, then — it’s about the air you actually breathe.

The right routine is straightforward. Before switching the AC on, open the windows for a minute and let the hot air escape. Then start the fan and bring the temperature down gradually. Aim the vents away from your face, neck and chest — point them at the windshield or upwards so the cold spreads through the cabin more gently.

The AC isn’t the enemy. The trouble starts when it gets treated like an “instant winter” button after an hour in the sun.