Cooling Problems
Your aircon is running but not cold, blows warm after a while, or never reaches the set temperature. Learn likely causes and what to check before calling a technician.
Why Your Aircon Is Not Cooling Properly
Cooling complaints are the most common aircon issue in Singapore. The unit runs, the fan blows, but the air is not cold — or it starts cold and turns warm after 10 to 15 minutes. In a tropical climate where outdoor temperatures regularly exceed 32 degrees, even a small drop in cooling performance is immediately noticeable.
The most frequent causes are a clogged filter restricting airflow, low refrigerant from a slow leak, or a dirty condenser coil on the outdoor unit. These account for roughly 80 percent of cooling failures. A simple filter wash and condenser rinse often restores full performance without any parts replacement.
If the air turns warm after running for a while, the compressor may be cycling off on high-pressure protection — usually caused by restricted airflow or an overcharged system. If cooling is weak in only one room while others are fine, the issue is likely localised to that indoor unit rather than the whole system.
Related Problems
Each article covers a specific symptom — what causes it, how serious it is, and when it needs professional attention.
Recent Cases
Real faults we diagnosed and resolved on site — what the owner reported, what we actually found, and how it was fixed.
Aircon Cassette Warm, Clogged Filter Found
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Aircon Cassette Warm, Dusty Condenser
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Aircon Cassette Warm, Stuck Expansion Valve
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Aircon Compressor Failed, Confirmed Faulty
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Aircon Condenser Choked With Debris
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Aircon Daikin C4 Thermistor Drift, Mid-Cycle Shutdown
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Aircon Dirty Evaporator, Not Low Gas
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Aircon Ducted Warm Zone, Stuck Damper
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Aircon Frozen Coil, Low Gas Cause
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Aircon Gas Leak at Outdoor Pipe Joint
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Aircon Gas Loss, Pinhole Leak Behind Wall
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Aircon Gas Loss, Salt Corroded Outdoor Joint
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Aircon Hidden Leak, Schrader Valve
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Aircon High Bill, Undersized Outdoor Unit
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Aircon Ice on Pipe, Not Just Low Gas
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Aircon LG Gas Leak Returns, Failed Weld
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Aircon LG Gas Leak, High-Floor Corrosion
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Aircon LG Gas Leak, Long Pipe Run
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Aircon LG Gas Leak, Not Compressor
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Aircon LG Gas Leak, Outdoor Pipe Connections
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Aircon LG Gas Leak, Outdoor Unit Replaced
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Aircon LG Gas Leak, Tenant-Landlord Dispute
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Aircon LG System-4 Gas Leak, All Rooms
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Aircon New BTO Undercharged Refrigerant
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Aircon Not Cold, Dirty Condenser Landed
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Aircon Panasonic F91 Refrigerant Fault, Choked Condenser
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Aircon Recurring Gas Loss in Woodlands
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Aircon Recurring Gas Loss, Slow Leak Found
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Aircon Refrigerant Leak vs Low Gas
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Aircon Refrigerant Top-Up Loop
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Aircon Salt-Crusted Condenser, Coastal Unit
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Aircon Sharp Error 2-0 Sensor Drift
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Aircon Two-Room Cooling Loss, Coil Leak
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Aircon York F1 Sensor Fault, Parts Delay
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Aircon York P1 High Pressure, Choked Condenser
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