If your aircon is running but not cooling, you’re not alone.
In Singapore, aircon systems are used almost daily due to the hot and humid climate. Over time, this constant usage can lead to reduced cooling performance or complete system failure.
The good news is that most aircon cooling issues can be identified early — and fixed before they become expensive problems.
⚠️ Why Your Aircon Is Not Cooling
If your aircon is blowing warm air or not cooling properly, it is usually due to one of these common causes:
- Dirty air filters
- Low refrigerant (gas leak)
- Blocked or dirty fan coil
- Faulty compressor
- Incorrect settings or thermostat issues
👉 Understanding the cause is the first step to fixing the problem.
🔧 1. Dirty Air Filters (Most Common Issue)
Air filters trap dust and dirt over time.
When clogged:
- Airflow becomes restricted
- Cooling efficiency drops
- Your aircon struggles to cool the room
👉 Fix: Clean your filters or schedule regular servicing.
❄️ 2. Low Refrigerant (Gas Leak)
Refrigerant is what allows your aircon to produce cold air.
If levels are low:
- Aircon blows warm or weak air
- Cooling takes much longer
- Energy usage increases
👉 Fix: A technician must check for leaks and perform a proper gas top-up.
🌀 3. Dirty Fan Coil or Blocked Airflow
When your system is dirty:
- Heat exchange becomes inefficient
- Cooling becomes uneven
- The system works harder than normal
👉 Fix: Chemical cleaning or professional servicing may be required.
If your aircon is still not cooling after basic cleaning, it may require a deeper chemical wash to restore full performance.
👉 Learn when a chemical wash is needed:
https://lioncityaircon.sg/when-does-aircon-need-a-chemical-wash/
⚡ 4. Faulty Compressor (Serious Issue)
The compressor is the heart of your aircon system.
If it fails:
- There will be little to no cooling
- The outdoor unit may not run
- Power trips may occur
👉 Fix: Requires professional diagnosis and repair or replacement.
🌡️ 5. Incorrect Settings or Thermostat Issues
Sometimes the issue is simple:
- Temperature set too high
- Wrong mode (fan instead of cooling)
- Faulty remote or thermostat
👉 Fix: Check your settings before assuming a major issue.
💡 Quick Checks Before Calling a Technician
Before booking a service, try these:
- Set temperature to 22–24°C
- Clean your air filters
- Ensure the outdoor unit is running
- Avoid using too many appliances at once
👉 These simple steps can solve minor problems instantly.
🔗 Related Guides
👉 Aircon leaking water? Read this:
https://lioncityaircon.sg/your-aircon-is-leaking-water/
👉 Aircon keeps tripping power? Read this:
https://lioncityaircon.sg/why-your-aircon-keeps-tripping-the-power-hdb-guide-singapore-2026/
👉 Full troubleshooting guide:
https://lioncityaircon.sg/troubleshoot/
👉 Not sure how often to service your aircon?
https://lioncityaircon.sg/how-often-should-i-service-my-aircon/
⚠️ When Should You Call a Professional?
You should contact a technician if:
- Your aircon is still not cooling after basic checks
- Cooling becomes weaker over time
- The system makes unusual noise
- Water leakage or power trips occur
👉 Delaying repairs can lead to higher costs later.
📞 Need Help Fixing Your Aircon?
At Lion City Aircon, we help homeowners:
- Diagnose cooling issues quickly
- Fix problems safely and effectively
- Restore strong and consistent cooling
- Prevent future breakdowns
👉 Contact us today for a proper inspection:
📞 Call / WhatsApp:
https://wa.me/6588185781
🌐 Book Online:
https://lioncityaircon.sg/booking/
📧 Email:
contact@lioncityaircon.sg
❓ Frequently Asked Questions
Why is my aircon running but not cooling?
This is usually caused by dirty filters, low refrigerant, or airflow issues.
Can low gas cause my aircon to stop cooling?
Yes. Low refrigerant is one of the most common causes of weak or no cooling.
How do I know if my compressor is faulty?
If there is no cooling and the outdoor unit is not running, the compressor may be the issue.
Can I fix aircon not cooling myself?
Basic cleaning and checks can help, but most issues require professional servicing.
How much does it cost to fix aircon not cooling?
It depends on the issue. Minor servicing is affordable, while major repairs cost more.
🔧 Related Aircon Cooling Problems
If your aircon is not cooling properly, the issue may be more specific than it seems. Here are some common related problems that can help you identify the exact cause:
If your aircon is blowing warm air instead of cold, this usually points to deeper issues like low refrigerant or compressor problems. Read more here:
👉 https://lioncityaircon.sg/why-your-aircon-is-blowing-warm-air-and-how-to-fix-it/
If your unit takes a long time to cool your room, airflow restrictions or dirty components could be the reason. Learn more:
👉 https://lioncityaircon.sg/does-your-aircon-take-too-long-to-cool-heres-why-and-how-to-fix-it/
If your aircon still feels weak even after servicing, there may be underlying faults that weren’t fully resolved. Find out why:
👉 https://lioncityaircon.sg/aircon-still-not-powerful-after-chemical-service-heres-why/
If your aircon is running but not cold enough, it could be due to incorrect settings, aging parts, or gas issues. See full guide:
👉 https://lioncityaircon.sg/why-is-my-aircon-not-cold-enough/
