Should I top up gas if the room is not reaching temperature?

Not without checking airflow and the filter first. Both airflow restriction and low refrigerant produce the same symptom. Airflow check is free and takes seconds. Gas top-up without finding a leak is money spent on a symptom, not a fix.

Could the problem be that my aircon is too small for the room?

Yes. If the unit was always marginal for the room size, you may only notice it on hotter days or when the room gains more heat than usual. We will assess whether the unit is underperforming or undersized and give you an honest answer.

My aircon reaches temperature at night but not during the day. Why?

Heat load. The afternoon sun adds significant heat to a room, especially west-facing rooms with glass. The unit may be performing correctly — the room is just hotter than it can handle in those hours. This is a room issue, not a unit fault.

Can I check anything before calling?

Yes. Pull out the filter from the indoor unit and look at it against the light. If it is visibly grey and matted, clean it and retest. Give it an hour to see if cooling improves. If the filter is clean and the issue continues, share your observations with us on WhatsApp.

Aircon Not Reaching Set Temperature

The unit is running and blowing cold air, but the room never gets to the temperature you set. There is a difference between a unit that is not cooling at all and one that is cooling, just not fully. That difference narrows your fault category significantly.

Common Causes

A symptom is just a starting point. The same problem could be a quick fix or a major failure. The paths below show the most common causes, but only a proper check can prove what is really wrong.

Airflow Restriction

Usually Minor

A clogged filter reduces how much cooled air reaches the room. The unit runs normally and the coil is cold, but air volume is too low to hit the set temperature. This is the most common cause and the easiest to check.

Airflow from the indoor unit feels weaker than before.
The room feels humid even when the aircon is running.
Cooling is uneven — near the unit is cooler than the far end of the room.

The Fix: A proper diagnosis is required to confirm the exact root cause and determine the necessary repair.

Watch out: Before agreeing to a refrigerant top-up or coil cleaning, ask whether the filter was checked first. Both faults produce the same symptom. Filter check costs nothing and takes seconds.

Refrigerant Below Optimal Level

Needs Diagnosis

If refrigerant is below the correct level due to a slow leak, the unit cannot extract heat from the room air efficiently. Airflow feels normal but cooling capacity is reduced. The room gets cooler than ambient, but never reaches the target.

Airflow still feels normal or close to normal.
The unit blows air that feels cool but not cold.
Cooling has been declining gradually over weeks or months.

The Fix: A proper diagnosis is required to confirm the exact root cause and determine the necessary repair.

Watch out: Topping up gas without finding and fixing a leak is a temporary fix. The refrigerant will drop again. Leak detection should come before any top-up.

Room Heat Load Too High for Unit Size

Usually Minor

Sometimes the unit is performing exactly as designed, but the room is generating or absorbing more heat than the unit's capacity can remove. This is a sizing or environmental issue, not a fault.

The problem is worst in the afternoon and eases in the evening when the sun moves.
Other rooms on the same system cool normally.
Unit is in a west-facing room with large windows or poor insulation.

The Fix: A proper diagnosis is required to confirm the exact root cause and determine the necessary repair.

Watch out: If this is the case, adding refrigerant or servicing will not help. We will tell you this honestly if that is what we find on-site. The fix is either a supplementary unit or window treatment — not a repair.

Not Always A Fault — The Room Matters More Than People Expect

West-facing rooms, large glass areas, poor ceiling insulation, and frequent door openings all add heat faster than the unit can remove it. A unit that is running correctly can still leave a room warm if the room is working against it.

How to tell if the room is the issue

Other aircons in the home reach their target temperature without issue.
The problem is only present during the hottest parts of the day.
Moving to a cooler room with the same unit size produces normal results.

If we find the unit is performing correctly and the room is the variable, we will say so. No unnecessary repair will be suggested.

What To Note Before You Contact Us

No disassembly needed. Observe with the unit running:

Airflow strength: weaker than before, about the same, or hard to tell.
Temperature of the air at the vent: noticeably cool, mildly cool, or hard to feel a difference.
Time pattern: does it fail to cool all day, or only during certain hours?
Room factors: sun exposure direction, curtains drawn or not, doors frequently in use.

The more specific your observations, the faster we narrow to one testable cause before visiting.

Stop Using The Unit If You Notice These

These are not cooling performance issues. These are safety signals.

Burning or electrical smell from the indoor or outdoor unit.
Breaker tripping when the aircon runs.
Ice forming visibly on the pipe or the outdoor unit coil.

Aircon Not Reaching Set Temperature

Common Causes

Airflow Restriction

Refrigerant Below Optimal Level

Room Heat Load Too High for Unit Size

Not Always A Fault — The Room Matters More Than People Expect

How to tell if the room is the issue

What To Note Before You Contact Us

Stop Using The Unit If You Notice These

Common Questions

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