Car aircon not cold? Singapore’s hot and humid weather makes a working car aircon more than a luxury, it’s essential.
But if your car’s aircon isn’t blowing cold air, or you notice a strange smell, it could be a sign of deeper problems.
In this guide, we’ll explain the most common causes of car aircon issues, how to spot early warning signs, and what you can do to prevent them. We shall start with understanding how your aircon system works and maintaining it properly.
How Your Car Aircon System Works (Quick Overview)
Your car’s air conditioning system uses several key components to cool the air:
- Compressor – pumps and circulates refrigerant gas.
- Condenser – removes heat from the refrigerant.
- Cooling Coil – absorbs heat from the cabin air to cool it down.
- Expansion valve – control the flow and cooling pressure.
When any of these parts fail or get blocked, you’ll start to feel your car’s aircon losing its chill.
Common Causes
1. Low Refrigerant
One of the most frequent causes of weak or warm air is low refrigerant (often called “aircon gas”). If your car has been running for 5 to 10 years and you start noticing that the aircon isn’t as cold as before but you’ve never serviced the aircon system (HVAC system), it doesn’t necessarily mean there’s a leak. The refrigerant may simply have dropped over time due to long-term usage. Some car aircon systems can even last until the end of their COE without major issues. To be sure, it’s best to have it checked by a professional workshop.
2. Gas Leak
One of the most frequent causes of weak or warm air is low refrigerant (often called “aircon gas”). Leaks can happen through worn-out seals, hoses, cooling coil, aircon stuck or connections over time. Simply topping up the gas won’t solve the issue. If it keeps leaking, it needs a proper inspection and sealing.
Tip: If you find yourself refilling aircon gas often, it’s likely there’s a leak somewhere in the system.
2. Compressor Problems
The compressor is the heart of your aircon system. If it fails or gets stuck, the refrigerant can’t circulate and results in warm air.
Common reasons include:
- Lack of lubrication
- Electrical issues
- Normal wear and tear
- Fanbelt not holding to the pulley properly( for fanbelt cars )
You might hear clicking or grinding noises when turning on the aircon if the compressor is struggling.
3. Clogged Condenser
Dust, leaves, and road debris can build up on the condenser, blocking airflow.
When airflow is restricted, your aircon can’t cool effectively and you’ll feel uneven temperature or weak air pressure.
Regular cleaning can keep these components efficient and prevent long-term damage.
4. Dirty Cabin Air Filter
A clogged air filter is one of the simplest yet most common issues. When the filter is full of dust, the air can’t pass through freely and causes weak airflow or a bad smell.
When to replace: Every 10,000 – 15,000 km, or sooner if you often drive in dusty areas.
5. Electrical or Sensor Faults
Modern aircon systems rely on electrical sensors and relays to control temperature and compressor operation. If a sensor fails, the aircon might cut off suddenly or fail to start.
These issues are often hard to detect without diagnostic tools, so a quick check at a workshop can save time and frustration.
6. Mould or Bacteria Build-Up
Humidity in Singapore can cause mould growth inside the aircon cooling coil and ducts. This leads to unpleasant odours or even allergic reactions.
A professional cooling coil cleaning service helps remove bacteria and restore fresh, cool air.
Warning Signs Your Needs Attention
Recognising early signs helps prevent a bigger breakdown later. Watch for these symptoms:
- Air not as cold as before
- Musty or sour smell
- Weak or uneven airflow from vents
- Aircon cuts in and out randomly
- Strange noises when aircon starts
- Water dripping inside the cabin
If you notice one or more of these, it’s time for a car aircon inspection.
How to Prevent Car Aircon Problems
Good maintenance can help your aircon last longer and perform better, especially in Singapore’s heat.
Here are some simple prevention tips:
- Run your aircon regularly – Keeps seals lubricated and refrigerant flowing.
- Change cabin filters on schedule – Clean air filters mean better airflow.
- Avoid using recirculation mode all the time – It traps humidity, encouraging mould growth.
- Clean your condenser area – Remove leaves or dirt from the front of the car.
- Have your aircon serviced yearly – Includes leak tests, pressure checks, and cleaning.
Conclusion
A car aircon that’s not cold doesn’t always mean a major repair but it’s a sign that something’s off. By understanding the common causes, recognising the warning signs, and following simple prevention tips, you can keep your car’s aircon cool and reliable all year round.
Feeling warm air from your vents? Don’t wait till it’s too late, visit TT Motorsport for a professional aircon check today.
Professional Aircon Service in Singapore
At TT Motorsport Singapore, we handle everything from simple gas refills to complex compressor replacements. Our experienced technicians use professional diagnostic tools to pinpoint the exact cause of aircon failure and not guesswork.
Whether your car’s aircon isn’t cold, smells bad, or blows weak air, we’ll help you get it back to top condition.
📍 Visit us at: TT Motorsport – Car Workshop in Singapore
🧰 Services include: Aircon servicing, maintenance, leak test, and repairs.
