Why is my car aircon blowing warm air?
The most common cause is low refrigerant, which usually means a leak somewhere in the system. Topping up without finding the leak often gives only short-term relief.
Other causes include a compressor that is not engaging, a faulty pressure switch, a blocked condenser at the front of the car, a failed cooling fan, or a blend door fault inside the dashboard. Some European cars also log aircon faults that can be read with a diagnostic tool.
Weak cooling can also build up slowly, so you may only notice it on a hot afternoon in traffic. If the air has been getting less cold over weeks, it is worth having it checked before it stops altogether.
Our guide on Audi aircon not cold covers a typical case.
How do you work out what is wrong with the aircon?
- We ask how the aircon behaves: warm all the time, cold then warm, or weak airflow.
- We check the compressor, belt, fans and visible lines and fittings.
- We test system pressures and look for leaks.
- We read the car's stored codes if the climate control reports a fault.
- We explain the findings and quote the repair.
- You approve it, and then we start.
Why does my car aircon smell?
A musty or sour smell usually comes from moisture and growth on the evaporator, also called the cooling coil, which sits behind the dashboard. In Singapore's humid weather the coil stays damp after you switch off, which encourages smells.
A cooling coil wash or cleaning can help in many cases, depending on the model and how the unit can be reached. A blocked drain or a dirty cabin filter can also add to the problem, so we look at these too.
What do aircon symptoms usually point to?
| Symptom | Possible area | What we check |
|---|---|---|
| Warm air all the time | Low gas, compressor, clutch | Pressures, leak test, compressor operation |
| Cold at first, then warm | Icing, expansion valve, fan | Pressures, condenser airflow, evaporator |
| Weak airflow | Cabin filter, blower, blocked coil | Filter, blower motor, coil condition |
| Musty smell | Dirty evaporator, damp unit | Coil, drain and cabin filter |
| Water in the footwell | Blocked evaporator drain | Drain line and housing |
The real cause can differ by model and fault, so this is only a starting point.
Do you check for gas leaks and compressor faults?
Yes. Leak and compressor checks are part of aircon diagnosis. A compressor can fail internally, or its clutch can stop engaging, and a leak can appear at hoses, seals, the condenser or the evaporator.
Once we know where the problem is, we explain the repair options and what they involve before anything is done.
Where can I get my aircon checked near Newton?
We are at 143 Bukit Timah Road, Newton Circus, inside the Shell station. Message us through the contact page with your car model and what the aircon is doing, and we will advise you on what to expect.
Questions owners ask
How much does aircon repair cost?
It depends on what is wrong, whether a gas top-up, a cleaning, or a part replacement. We do not give a number before inspection. After checking, we give you a quote, and you agree to it before any work starts.
Is a gas top-up enough to fix my aircon?
Sometimes, but if gas has run low there is usually a leak, so a top-up alone may not last. We check for the leak so you can decide whether to repair it or simply top up.
What is a cooling coil wash?
The cooling coil, or evaporator, cools the air before it enters the cabin and can collect dirt and moisture. A wash or cleaning helps remove build-up that causes smells and weaker cooling. Whether it suits your car depends on the model.
How do I know if my compressor has failed?
Signs include warm air, noise when the aircon is switched on, or a compressor clutch that does not engage. These can also come from other faults, so we test pressures and operation before we say the compressor is the problem.