Aircon Case Studies
Use this category when you want evidence from real jobs before committing to scope.
15 real jobs showing how a symptom was assessed, what diagnosis was confirmed, and what scope was actually needed. Use these when you want evidence before approving a repair recommendation.
All Case Studies
Each case shows the complaint, what was checked, the actual cause, and the advised scope.
Electrical misdiagnosis
Breaker Trips, Not Compressor Short
Trips and hot smell were traced to a damaged isolator connection, not compressor failure.
Toa Payoh, Singapore • LG
Airflow restriction pattern
Cold But Weak Airflow
Weak airflow was traced to buildup pattern before motor replacement was considered.
Bishan, Singapore • Mitsubishi Electric
Major vs targeted repair
Compressor Vs Capacitor Failure
Major replacement was advised first, but targeted testing found a smaller failure.
Jurong West, Singapore • Panasonic
Post-work wiring fault
Flashing Light After Renovation, Not PCB Replacement
Flashing errors started after nearby work because a communication-wire connection was disturbed, not because the PCB failed.
Serangoon, Singapore • Mitsubishi Electric
Leak path found
Hidden Leak At Schrader Valve Core
A small service-port valve-core leak kept causing repeat cooling loss after quick checks missed the leak path.
Yishun, Singapore • Midea
Freeze-up pattern
Ice On Pipe, Not Just Low Gas
Pipe icing followed an airflow restriction pattern, so a top-up-first fix would have missed the real cause path.
Ang Mo Kio, Singapore • Daikin
Severe airflow restriction
No Airflow, Not Fan Motor Replacement
Very low airflow was caused by heavy blower-wheel buildup, so a fan motor replacement would have been the wrong first fix.
Kallang, Singapore • Panasonic
Post-service failure
Not Cold After Servicing
Cooling failed soon after service because one service step was incomplete.
Bedok, Singapore • Daikin
One-room cooling pattern
One Room Not Cold, Not Low Gas
One warm room was narrowed to a room-specific indoor airflow and coil issue, not a system-wide gas problem.
Queenstown, Singapore • Mitsubishi Heavy
Noise misdiagnosis
Outdoor Noise At Night, Not Compressor Failure
Night rattling was vibration transfer from mounting points and bracket hardware, not a failed compressor.
Woodlands, Singapore • Mitsubishi Electric
Outdoor start-path fault
Outdoor Unit Not Running, Contactor Relay Fault
The outdoor side did not start because of a contactor relay fault, while the indoor side kept running and made the problem look bigger.
Punggol, Singapore • Daikin
Recurring cooling loss
Refrigerant Leak, Not Just Low Gas
Repeated top-ups were masking one leak path that needed proper repair.
Tampines, Singapore • Mitsubishi Electric
Signal-path misdiagnosis
Remote Not Working, Not Indoor PCB
Remote command failure was traced to the IR receiver path, not a full indoor PCB replacement case.
Pasir Ris, Singapore • Sharp
Recurring gas loss
The Refrigerant Top-Up Loop
Three gas top-ups in one year — a leaking flare joint was the cause no one had checked.
Sengkang, Singapore • Mitsubishi Electric
Post-service leak
Water Leak After Chemical Wash
Indoor dripping started after a chemical wash because the drain path was not seated correctly during reassembly.
Hougang, Singapore • Panasonic
Next Step
If you are still diagnosing the pattern (before comparing real job outcomes), start with the symptom guides and narrow the likely fault path first.
Practical aircon articles and real case studies for Singapore homes.