Aircon Diagnostic Cases

Bishan HDB unit blowing cold air but airflow kept weakening each week. We opened the unit and traced it to heavy buildup on the fan barrel and coil.

Teck Ghee HDB unit worked in the morning but cut out every afternoon. Outdoor unit in an alcove with blocked airflow. Thermal protection was tripping.

Changi landed home breaker trips clustered around rainy evenings. Compressor tested normal. Rusty outdoor switch box with failed seals was the cause.

Daikin C4 caused mid-cycle shutdowns in Clementi. Thermistor had drifted with age. Not wiring or PCB. Sensor replaced in 20 minutes.

All four units in a Tampines condo showed LG CH05 at once. Wiring tested fine. Outdoor PCB had failed. Replaced the board.

All four rooms in a Sengkang HDB lost cooling simultaneously. The LG outdoor unit had a gas leak at the pipe connections, requiring full system replacement.

Jurong East HDB aircon auto mode kept shutting off every few minutes. Sensor was reading 19 degrees in a 26-degree room. One part swap restored stable cycling.

Changi Village HDB wall unit buzzing loudly when running. Mounting plate had loosened from the wall. Resecured bracket stopped the noise. Compressor was fine.

Tengah BTO unit was never cold from day one. System was undercharged by the installer for the pipe run length. Topped up to correct charge and cooling started.

Toa Payoh HDB breaker trips with a hot smell pointed to compressor failure. Heat-damaged isolator connection was the actual cause. No compressor work needed.

Cafe unit in Outram losing cooling despite quarterly servicing. Thick grease sludge on evaporator. Chemical overhaul restored cooling, no parts needed.

MHI unit in Jurong East still faulted after a capacitor swap. The outdoor PCB driver circuit had no output to the compressor. Board replacement fixed it.

Hougang HDB ceiling cassette with weak airflow. Corroded motor contacts were reducing fan speed, not a blocked filter. Motor contacts cleaned and restored.

Cassette unit in Choa Chu Kang leaking onto office equipment. Drain line was fully blocked with sludge. Drain pan was intact. Drain flush fixed it.

Marina Bay condo cassette leaking water during heavy tropical rain. Drain line froze briefly from extremely cold aircon output. Cleared and insulated the line.

Joo Koon factory office cassette blowing warm air. Electronic expansion valve was stuck partially closed, restricting refrigerant flow. Compressor was fine.

Dhoby Ghaut office cassette rattled at medium fan speed. Loose fan blade retaining clip was the actual cause, not compressor bearing fault.

Raffles Place office cassette started dripping after routine filter cleaning. Drain trap had lost its water seal. No cracked coil, no pump fault.

Intermittent ceiling drip in Marina South office persisted after a drain replacement. A concealed joint gap upstream was the actual source.

Daikin A3 on a ceiling-concealed unit in Bukit Timah. Condensate pump motor had failed. Water backed up. Replaced the drain pump.

Dhoby Ghaut office ceiling unit dripped after quarterly service. Drain fitting was loose from reassembly. Reconnected and tested. Leak stopped.

LG CH10 in Woodlands HDB. Diagnosed as PCB fault. Actual cause was a cracked blower wheel catching on the housing. Wheel replaced, motor fine.

Katong condo aircon blowing but not cold. Previous company said gas leaked and coil needed replacing. Chemical servicing of caked evaporator restored cooling.

Sentosa condo aircon topped up twice in one year. Salt-air corrosion had thinned the flare nut at the outdoor pipe joint. Replaced the fitting. Gas holds now.

Novena condo concealed unit dripping from two points. Condensate pump had seized from scale buildup. Pump replaced, dripping stopped.

Serangoon HDB cooling dropped and water dripped after a chemical servicing. Drain pan cover and blower wheel both left out of position during reassembly.

Upper Thomson landed home wall unit dripping intermittently on humid days. Drain pipe had sagged over the years. Resupported pipe to restore gradient.

Orchard office ducted system gradually lost airflow. Staff feared duct deterioration. Return air filter in the ceiling void had not been cleaned in years.

Panasonic H11 error appeared after a power trip in Bedok. Traced to a loose terminal at the indoor PCB connector block. Re-seated connections cleared the fault.

Marina East condo error code appeared right after servicing. PCB was locked in fault state from abrupt power cut. Manufacturer reset sequence cleared it.

Tengah HDB error code appeared right after renovation. Signal wire had been nicked and rejoined with wires swapped. Correcting the sequence cleared the error.

LG CH05 appeared intermittently in Ang Mo Kio HDB. Quoted outdoor PCB replacement. Actual fault was a corroded terminal. Cleaned and re-crimped.

Daikin A3 kept returning after drain clearing in Toa Payoh. A sag in the drain line inside the false ceiling trapped sludge. Rerouted the line.

Mitsubishi E6 in Yishun traced to a corroded wire splice in a ceiling void junction box. Weatherproof re-splice resolved it.

York E1 in Jurong East HDB. Previous contractor could not diagnose it. Corroded outdoor terminals. Cleaned and re-crimped to clear the fault.

Samsung E1 after renovation in Jurong West HDB. Cable insulation nicked during drilling. Exposed wire shorted against trunking. Fixed with no parts replaced.

On-and-off aircon trips in a Sungei Kadut factory office traced to a corroded isolator switch. Wiring was intact. No cable replacement needed.

Cassette unit in Tuas factory losing cooling gradually. Condenser coil coated in industrial dust. Chemical servicing restored full capacity.

Telok Blangah HDB aircon not cold at five years old. Condenser coil was crusted with salt residue from sea breeze. Chemical servicing restored cooling.

An LG outdoor unit on a high-floor Punggol condo corroded in just 4 years due to direct wind and rain exposure, causing a gas leak far earlier than expected.

Newton condo unit topped up twice in one year but kept losing cooling. A pinhole leak in the concealed copper pipe behind the wall was the cause.

A welded gas leak on an LG outdoor unit in Woodlands failed again. Cooling returned briefly before a new leak appeared on the same corroded pipe section.

Yishun HDB with repeated cooling loss after multiple top-ups. Focused leak checks on the service port traced the hidden source to a faulty Schrader valve core.

Macpherson HDB case: regular servicing missed deep evaporator coil fouling. Chemical servicing reopened the coil and restored cooling.

Sharp 6-0 in Woodlands HDB. Fan motor grinding on a 13-year-old unit. Bearings worn out. Owner chose replacement over repair given the age.

Ang Mo Kio condo with three ceiling cassettes struggling to cool and high monthly bills. Outdoor unit was too small for the indoor capacity.

Ang Mo Kio Daikin with ice on pipe. Assumed low gas. Airflow pattern and coil condition pointed to buildup restricting the evaporator, not a refrigerant issue.

Punggol HDB indoor unit blew air but the outdoor side stayed silent. A contactor relay fault in the start path was the cause. Not a compressor failure.

Dairy Farm landed home aircon gradually lost cooling. Told the compressor was failing. Outdoor condenser was choked with leaf litter from nearby trees.

LG CH35 case in Bedok: leak tracing found corroded outdoor pipe connections. After sealing and recharge, cooling returned without parts replacement.

LG system 3 in Serangoon had a gas leak along a long pipe run. Nitrogen testing narrowed it to the outdoor unit connections, not the concealed piping.

Cooling kept dropping after gas top-ups in Bukit Batok. We traced the leak to corroded LG outdoor unit connections and presented three repair options.

Clementi HDB wall unit rattled loudly during startup then went quiet. Mounting was solid. Worn motor bearings let the rotor shift during spin-up.

Brand-new unit in Tampines never reached set temperature. Installer said it needed time to settle in. Refrigerant was 35% below spec from day one.

Cashew condo unit shut down every few hours with no error code. PCB had already been replaced by another company. A drifted room thermistor was the cause.

New multi-split system in Bukit Panjang cooled unevenly. Two control wire pairs swapped at the terminal block during installation.

A new aircon unit in Tengah started leaking after its first service. The drain pan had not been reseated properly, not a defective unit.

Queenstown condo with only one room staying warm while others cooled normally. Fault was in the indoor airflow and coil condition, not a system-wide gas issue.

Straits View office ducted system with one zone getting warm air while others stayed cold. Motorised zone damper had jammed near-closed. Freed the actuator.

Daikin cassette in Geylang cooling one side poorly. Stuck louver vane and partial coil fouling on that section. Fixed without any parts.

Samsung E1 on one unit in a Sengkang condo system-3. Other two worked fine. PCB swap test confirmed indoor board fault. Replaced it.

Jurong West HDB outdoor unit buzzing but not starting. Sounded like compressor failure. Capacitor test pinpointed the cause, one swap restored cooling.

Choa Chu Kang Daikin outdoor unit went silent. We tested and cleared the capacitor, contactor, and relay before confirming an open compressor winding failure.

Outdoor unit rattling loudly at night in Woodlands HDB. Mounting rubber had hardened and bracket bolts loosened. No compressor fault.

Sharp 7-0 in Bedok. Outdoor unit not starting. Diagnosed as compressor failure. We found a failed capacitor instead. A forty-dollar fix.

Boon Lay HDB unit had no airflow despite clean filters and blower. Motor winding check showed open circuit. Burnt motor, not blockage.

Bedok HDB unit stopped cooling two days after routine service. Service valve left partially closed, restricting refrigerant flow. No parts needed.

Kampong Glam shophouse unit smelled musty even after servicing. Mould had colonised the evaporator coil fins behind the filter. Chemical servicing resolved it.

Mitsubishi E6 in Bishan condo appeared only when the drain pump ran. Communication cable alongside pump cable caused interference.

Wall unit rattling on startup in Boon Keng. Quoted for fan motor replacement. Blower barrel setscrew was loose. Tightened and noise stopped.

Pasir Ris HDB remote stopped controlling the unit. Power light was on but no buttons responded. The IR receiver had failed, the main indoor PCB was fine.

Paya Lebar HDB unit started short cycling right after servicing. Previous company said sensor failure. Thermistor was displaced from its clip during cleaning.

River Valley office with one room staying warm while others cooled normally. We confirmed a jammed damper linkage, not low refrigerant or compressor failure.

All three Starmex units showed E7 at once in Punggol. Wiring was clean. Outdoor PCB had stopped receiving signals. Board replacement resolved it.

Canberra HDB cooling faded across two linked bedrooms after repeated top-ups. Leak tracing confirmed a pin-hole leak at an indoor coil return bend.

Seletar industrial cassette blowing unevenly across vanes. Compacted dust on one side of the blower wheel caused the imbalance. Chemical clean restored it.

Clementi HDB cooling faded after every top-up. We ran a pressure test overnight and traced the leak to the indoor flare joint. No more repeated top-ups.

Balestier HDB wall unit dripping onto bedroom floor. Drain tray was choked with algae blocking the outlet. Cleaned tray and flushed drain. Drip stopped.

Ducted unit water overflow in a Tanglin landed home was caused by a stuck condensate pump float switch, not a failed pump needing full replacement.

Buona Vista condo system-4 tripped whenever one bedroom unit was switched on. A faulty indoor PCB in that unit was triggering the outdoor protection circuit.