Aircond Not Cooling? 8 Things to Check Before Calling a Technician
Your aircond is running but not cooling? Check these 8 things before calling for repair. Some fixes you can do yourself and save money.
It’s 33°C outside in Kuala Lumpur, and your aircond is running, but the room just isn’t getting cold. It is frustrating, especially when you just want to relax after a long commute.
Before you panic and call for a repair, there are several things you can check yourself. We see this happen constantly with homeowners in Puchong and KL. Often, the issue is a simple setting or maintenance oversight rather than a broken part.
Let’s go through the exact checklist our team uses to troubleshoot these problems.
Check #1: Is the Temperature Set Correctly?
Seems obvious, but…
- Check that the set temperature is lower than the current room temperature.
- Someone might have accidentally changed it.
- Remote control batteries might be low, causing the unit to miss the signal.
The “Eco Mode” Trap: Many modern Daikin and Panasonic remotes feature an “Eco” or “Econo” mode (often a symbol of a leaf or a down arrow with a line). This limits the compressor’s power to save electricity. While great for bills, it often struggles to cool a hot room during a Malaysian afternoon.
What to do:
- Set the temperature to 23-24°C and wait 10-15 minutes.
- Disable “Eco” or “Sleep” modes if they are active.
- Replace remote batteries if the display looks dim.
Check #2: Are the Air Filters Clean?
Why it matters: Dirty filters block airflow, drastically reducing cooling efficiency. This is the #1 cause of poor cooling that you can fix yourself.
The Hidden Cost: According to data from Tenaga Nasional Berhad (TNB), a dirty air conditioner can consume up to 25% more electricity to provide the same cooling. This inefficiency can easily push your monthly usage into the next tariff tier (jumping from 21.80 sen/kWh to 51.60 sen/kWh for usage above 200-300 units).
Signs of dirty filters:
- Weak airflow from vents.
- Dust visible on the filter mesh.
- You haven’t cleaned them in over a month.
What to do:
- Turn off the aircond at the wall switch.
- Open the front panel carefully.
- Remove the plastic filters.
- Wash them with water (no soap needed) in your bathroom.
- Dry them completely before reinserting.
- Run the aircond again.
Result: If dirty filters were the issue, you’ll notice better cooling within 30 minutes.
Check #3: Is the Outdoor Unit Blocked?
Why it matters: The outdoor unit (compressor) releases heat from your home. If it’s blocked, that heat gets trapped, and the system can’t cool the refrigerant back down.
Common “High-Rise” Problems: In many condos around Puchong and KL, we find compressors installed in tight balcony corners. Homeowners often unknowingly block them with:
- Drying racks full of clothes.
- Stacked potted plants or storage boxes.
- New renovations or partitions.
What to do:
- Clear at least 1-2 feet of space around the back and front of the unit.
- Remove leaves, plastic bags, or debris stuck to the back fins.
- Check if the fan is spinning vigorously when the AC is on.
- Gently hose down the condenser coils (from top to bottom) if you have access.
Check #4: Is the Aircon the Right Size for Your Room?
Why it matters: An undersized aircond will run constantly but never cool the room adequately. In our tropical climate, standard “Western” sizing charts often fail because they don’t account for our consistent heat and humidity.
Malaysia Sizing Guide (Aggressive Cooling):
| Room Size (sq ft) | Recommended HP | Ideal For |
|---|---|---|
| Up to 120 | 1.0 HP | Small Bedroom |
| 120 - 180 | 1.5 HP | Master Bedroom |
| 180 - 250 | 2.0 HP | Living / Dining |
| 250 - 350 | 2.5 HP | Large Open Plan |
Consider also:
- Glass Walls: Floor-to-ceiling windows (common in new condos) act like greenhouses. Add 0.5 HP.
- West-Facing: If your room gets the 4 PM sun, you absolutely need the next size up.
- Top Floor: Roof heat radiates down, increasing the cooling load significantly.
If undersized: Unfortunately, the only fix is upgrading to a larger unit.
Check #5: Are Doors and Windows Properly Closed?
Why it matters: Cool air escapes through gaps, and hot, humid air enters. Your aircon ends up fighting a losing battle against the outside weather.
Common issues:
- Windows not fully latched.
- Large gaps under doors (especially in older landed properties).
- Curtains left open during the hottest part of the day.
What to do:
- Check that all windows are sealed tight.
- Install simple door sweeps to seal gaps under doors.
- Close blackout curtains on sunny sides to reduce heat gain.
- Minimize opening doors while the cooling cycle is starting.
Check #6: Is There Ice on the Unit?
Why it matters: Ice on the coils blocks airflow and prevents cooling. It is usually a sign of a more serious issue like a gas leak or a completely choked system.
Causes of icing:
- Low refrigerant (gas leak).
- Extremely dirty coils restricting airflow.
- Faulty fan motor.
What to do:
- Turn off the aircond immediately.
- Let the ice melt completely (this may take 2-4 hours).
- Check your filters; if they are clogged, clean them.
- If the ice returns after restarting, call a technician.
Warning: Running an iced-up unit places extreme stress on the compressor, which is the most expensive part to replace.
Check #7: When Was the Last Service?
Why it matters: Over time, a “jelly” of dust and moisture builds up on your cooling coils. This prevents the air from touching the cold coils, reducing cooling efficiency by up to 30%.
The “Chemical Wash” Standard: If it has been over 6-12 months since your last service, a basic vacuum isn’t enough. You likely need a chemical wash. In the KL/Selangor market, a proper chemical wash typically costs RM130 - RM180 for a wall unit.
Signs you need a chemical wash:
- Gradual decline in cooling over weeks.
- Musty or sour smell when the unit starts.
- Water dripping from the indoor unit.
Insider Tip: Be wary of ads offering “RM60 Chemical Service.” These are often bait. The technicians may claim you have “zero gas” to upcharge you hundreds of Ringgit. Real, thorough cleaning takes time and proper chemicals.
Check #8: Is the Mode Set Correctly?
Common mistake: The aircond might be set to “Fan Only” or “Dry” mode instead of “Cool” mode.
Check the remote:
- Cool Mode: Look for the snowflake icon ❄️. This is what you want.
- Dry Mode: Look for the water drop icon 💧. This reduces humidity but doesn’t cool as aggressively.
- Fan Mode: Look for the fan icon. This just blows air without cooling.
Also check:
- Sleep mode: This often raises the temperature by 1-2°C every hour to prevent you from getting too cold at night.
- Timer: Ensure no “Off” timers are accidentally set.
Summary: What You Can Fix Yourself
| Issue | DIY Fix? | Difficulty |
|---|---|---|
| Wrong settings | Yes | Easy |
| Dirty filters | Yes | Easy |
| Blocked outdoor unit | Yes | Easy |
| Doors/windows open | Yes | Easy |
| Ice on coils | Partially | Medium |
| Dirty coils | No | Need professional |
| Low gas | No | Need professional |
| Compressor issues | No | Need professional |
When to Call a Professional
Call a technician if:
- ✓ You’ve checked all the above and still get no cooling.
- ✓ Ice keeps forming on the indoor or outdoor unit.
- ✓ The outdoor unit fan isn’t spinning at all.
- ✓ You hear grinding or buzzing noises from the compressor.
- ✓ No cold air comes out at all (potential compressor failure).
- ✓ It hasn’t been serviced in over 6 months.
We Can Help
Tried everything and still sweating? We offer transparent, reliable service across Puchong and KL.
- Diagnostic service - RM50 (waived if you proceed with repair).
- Chemical wash - RM160/unit (Deep cleaning that restores factory freshness).
- Repair - Clear quotes based on actual diagnosis, no hidden “gas fees.”
WhatsApp us with your issue and we’ll advise if you need a service call.
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