Car air conditioning in summer: symptoms not to ignore
Cools less, smells odd or drips inside. What each symptom means and what to check before regassing.
Around here air conditioning is not a luxury: between June and September the car spends hours in the sun and the cabin reaches temperatures that damage plastics and wear out the driver. Failures rarely arrive suddenly — they warn you first.
It cools less than last year
The most common symptom and the most misread. Many people simply ask for a regas, but a sealed circuit does not consume refrigerant: if it is low, it is escaping somewhere. Recharging without finding the leak means paying twice.
Before touching the gas it is worth checking the cabin filter, the condenser in front of the radiator (on the coast it fills with dust and salt) and that the fan starts as it should.
A damp smell when you switch it on
The smell comes from the evaporator: trapped moisture plus dust equals a bacterial colony. It usually comes with windows misting more than normal. It is treated by cleaning the system and changing the filter; if that filter has seen two summers, it is half the problem.
Water dripping inside the car
A puddle under the passenger mat is almost always a blocked evaporator drain: condensation cannot get out and enters the cabin. Cheap to fix, expensive to ignore, because the damp ends in a permanent smell and corrosion under the carpet.
Noise when the air comes on
A dry click on activation and a noise that only appears with the air on point at the compressor clutch or the belt tension. Look at that early: a seized compressor is one of the most expensive repairs in this system.
What a normal check covers
- Outlet temperature at the vents and how the system behaves. - Cabin filter and the state of the evaporator. - Condenser, fans and cleanliness of the front end. - Circuit pressures and leak testing with dye if needed. - Belt, pulleys and compressor operation.
One habit that extends the system's life
Run the air for a few minutes in winter too, once a month. The compressor needs the oil to circulate; the systems that sit idle for half a year are the ones that fail on the first hot day. And before parking in the sun, air the car out for a minute with the windows down: it drops the load on the system a lot at start-up.