cassette · Repair · Diagnosis
Ceiling cassette aircon repair in Singapore
Ceiling cassettes combine an indoor fan, lift-pump drainage, float protection and four-way air distribution above a finished ceiling. We identify whether the fault is local, shared, mechanical, electrical or refrigerant-related before recommending work.
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Signs your cassette system needs repair
The visible symptom identifies where to start, not the replacement part.
Water appears around the ceiling panel
A blocked pipe, stalled drain pump, float protection or damaged drain pan can stop condensate from leaving the unit.
Airflow is weak or uneven
A loaded coil, blower problem, vane fault or indoor fan circuit can affect one or more discharge sides.
The controller shows a recurring fault
Cassette codes can identify drainage, fan, sensor, communication, board or shared outdoor-system paths.
The cassette systems we repair
These examples describe the main equipment layouts we encounter. The list is not a model restriction.
Four-way and compact ceiling cassettes
Send the indoor and outdoor model labels so we can confirm the exact service and diagnostic scope.
Cassette indoor units connected to multi-split or VRF outdoor systems
Send the indoor and outdoor model labels so we can confirm the exact service and diagnostic scope.
Commercial cassette systems with wired controllers and condensate pumps
Send the indoor and outdoor model labels so we can confirm the exact service and diagnostic scope.
Confirm your system
Diagnosis normally starts from below the panel. Ceiling height, safe access, drain routing and whether the cassette can be lowered affect the repair scope. A cassette fault can be local to one indoor unit or come from the shared outdoor system, so the indoor and outdoor model labels matter.
What can look like a component failure
We check these system-level causes before a major electrical or refrigerant repair is quoted.
Cleaning before component repair
A fouled coil, blower or drain pan can create cooling, airflow and water symptoms without a failed electrical part.
Drainage route outside the cassette
Backfall, a blocked common line or a failed external pump can leave the indoor cassette operating correctly but unable to drain.
Shared outdoor-system fault
If several connected rooms stop together, the compressor, outdoor PCB, power or communication path may be the real starting point.
Official cassette fault-code evidence
935 model-scoped fault guides across 10 supported brands help identify where diagnosis should start on this equipment type.
Carrier99 guides
- 0ARepeated central-control address
- 0C50 Hz zero-crossing fault
- 01Indoor ambient temperature sensor Ta failure
- 02Indoor coil temperature sensor Tc1 failure
- 03Indoor coil temperature sensor Tc2 failure
- 04Indoor TW sensor failure
- 05Indoor EEPROM failure
- 06Communication failure between indoor and outdoor units
- 07Communication failure between indoor unit and wired controller
- 08Indoor drainage failure
- 09Repeated indoor-unit address
- 20 / 20-0Defrosting temperature sensor Tdef failure
- View all Carrier error-code guides
Fujitsu103 guides
- 3AIndoor unit communication circuit (wired remote controller) error
- 4AIndoor unit air temp. thermistor error
- 5AIndoor unit fan motor 3 error
- 5UIndoor unit miscellaneous error
- 6AOutdoor unit display PCB error
- 9AOutdoor unit coil (expansion valve) error
- 9UOutdoor unit miscellaneous error
- 11Serial communication error between indoor/outdoor units
- 12Remote controller communication error
- 13Communication error between Outdoor unit
- 14Network communication error
- 15Scan error
- View all Fujitsu error-code guides
Gree142 guides
- 43 / 44 / 45 / 46Communication failure with Unit A
- 47 / 48 / 49 / 50Unit A freeze protection
- 51 / 52 / 53 / 54Unit A overheating prevention protection
- 55 / 56 / 57 / 58Unit A communication wire misconnection or expansion valve malfunction
- AbEmergency stop of operation
- b1Malfunction of Outdoor Ambient Temperature Sensor (RT7) (CN421 Blue)
- b2Malfunction of Defrosting Temperature Sensor (RT3) (CN422 White)
- b4Malfunction of Sub-Cooler Liquid Outlet Temperature Sensor (RT5) (CN416 Red)
- b5Liquid valve temperature sensor is open or short-circuited
- b6Malfunction of Accumulator Inlet Temperature Sensor (RT1) (CN422 White)
- b7Gas valve temperature sensor is open or short-circuited
- b9Malfunction of heat-exchanger temperature sensor
- View all Gree error-code guides
Hitachi56 guides
- 0AAbnormal communication between outdoor units
- 0bIncorrect sub-outdoor-unit address setting
- 0CIncorrect outdoor main-unit setting
- 01Indoor-unit float-switch protection activated
- 1AIndoor fan-controller fin-temperature abnormality
- 1bIndoor fan-controller overcurrent protection activated
- 1CIndoor fan-controller current-sensor problem
- 1dIndoor fan-controller protection activated
- 1EIndoor fan-controller voltage abnormality
- 02Outdoor-unit high-pressure protection activated
- 03Abnormal communication between indoor and outdoor units
- 3AOutdoor-unit capacity abnormality
- View all Hitachi error-code guides
LG72 guides
- 51C / -51C + HR unit numberheat-recovery unit: Connected indoor-unit capacity exceeds the heat-recovery-unit allowance
- 201C / 201C + HR unit numberheat-recovery unit: Heat-recovery-unit liquid-pipe sensor error
- 202C / 202C + HR unit numberheat-recovery unit: Heat-recovery-unit subcooling-inlet sensor error
- 203C / 203C + HR unit numberheat-recovery unit: Heat-recovery-unit subcooling-outlet sensor error
- 204C / 204C + HR unit numberheat-recovery unit: Communication error between the outdoor unit and heat-recovery unit
- 205C / 205C + HR unit numberheat-recovery unit: Communication error between a 2A-series heat-recovery unit and its 485 modem
- 206C / 206C + HR unit numberheat-recovery unit: Duplicate 2A-series heat-recovery-unit address
- 242*central controller: Central-controller network communication error
- 511system: Indoor/outdoor nominal-capacity combination ratio is out of range
- 512system: Indoor-unit capacity exceeds the allowable heat-recovery branch capacity
- 2001heat-recovery unit: Heat-recovery auto-pipe search failed
- CH01indoor unit: Indoor return-air or remote wall temperature sensor communication error
- View all LG error-code guides
Midea103 guides
- A01Emergency shutdown
- A11R32 refrigerant leak requiring immediate shutdown
- A51Outdoor-unit fault
- A71Heat-recovery ventilation interlock control fault (serial application)
- A72Humidification-unit fault
- A73Heat-recovery ventilation interlock control fault (non-serial application)
- A74Secondary AHU-kit fault
- A81Self-check fault
- A82MS refrigerant-flow direction switching device fault
- A91Mode conflict
- b11EEV No. 1 coil fault
- b12EEV No. 1 valve-body fault
- View all Midea error-code guides
Mitsubishi Electric39 guides
- 05 / LED 11x / Outdoor LED: 11 blinks / UEStop valve or closed valve
- E0Remote-controller receiving error
- E1Remote-controller control-board memory error
- E2Remote-controller clock-function error
- E3Remote-controller transmitting error
- E4Indoor controller cannot receive the remote-controller signal
- E5Indoor controller cannot transmit on the remote-controller path
- E6 / E7Indoor-outdoor communication receiving error
- E8 / e8Serial signal
- E9 / e9Indoor-outdoor unit communication error
- EdSerial communication error between outdoor boards or M-NET communication error
- EEIndoor-outdoor unit combination error
- View all Mitsubishi Electric error-code guides
Mitsubishi Heavy Industries50 guides
- E1 / RUN 2x / TIMER 2xCommunication fault between the remote controller and indoor unit
- E4Indoor-unit address-setting limit exceeded
- E5Indoor/outdoor communication fault
- E6Indoor heat-exchanger sensor fault
- E7Indoor return-air sensor fault
- E8Heating overload protection
- E9Drain fault
- E10Too many indoor units connected to one remote controller
- E13Air-cleaner fault
- E14Communication fault between master and slave indoor units
- E16Indoor fan motor fault
- E19Operation-check mode fault
- View all Mitsubishi Heavy Industries error-code guides
Samsung167 guides
- Blue + red blinkingIndoor-unit fan error
- Blue blinkingOutdoor-unit error is being reported by the indoor unit
- E101 / E102 / E101 / E102Indoor unit communication error. Indoor unit cannot receive any data from the outdoor unit.
- E108Error due to repeated address setting (when two or more devices have the same address within the network)
- E121Error on indoor temperature sensor of indoor unit (Short or Open)
- E122Error on EVA IN sensor of indoor unit (Short or Open)
- E123Error on EVA OUT sensor of indoor unit (Short or Open)
- E128EVA IN temperature sensor of indoor unit is detached from EVA IN pipe
- E129EVA OUT temperature sensor of indoor unit is detached from EVA OUT pipe
- E130Heat exchanger in/out sensors of indoor unit are detached
- E135RPM feedback error of indoor unit's cleaning fan
- E149Error due to AHU master indoor unit sensor setting
- View all Samsung error-code guides
Toshiba104 guides
- C05Central controller transmission fault
- C06Central controller reception fault
- C12General-purpose device control interface alarm
- E01Remote controller cannot receive signals from the indoor unit
- E02Remote controller cannot transmit signals to the indoor unit
- E03Indoor unit lost communication from the remote controller or network adaptor
- E04Indoor unit is not receiving signals from the outdoor unit
- E06An indoor unit dropped out of normal communication
- E07Outdoor unit cannot transmit signals to indoor units
- E08An indoor-unit address is duplicated
- E09Two remote controllers are both configured as master
- E10Indoor main-controller to motor-microcontroller communication fault
- View all Toshiba error-code guides
A code can be relayed from another indoor, outdoor or controller. Match the brand, model and reporting location before following a guide.
How cassette repair works
The visit narrows the fault from system layout to the exact circuit before a quote is approved.
Confirm the cassette and outdoor models
The panel, controller and model stickers identify the drainage layout, fan circuit and matching diagnostic table.
Inspect the accessible mechanical path
We check the panel, filters, coil, blower, drain pan, pump, float and pipe route before isolating an electrical part.
Test the reported circuit
The code, wiring, board command, sensor feedback and shared outdoor operation are compared before parts are quoted.
Repair, correct the installation, or replace
The right outcome depends on which part of the complete system is responsible.
Repair the local cassette
A serviceable pump, fan, sensor, vane, wiring or board fault can usually be isolated without replacing the complete system.
Correct access or drainage first
Poor access, pipe backfall or a common drainage blockage must be corrected before a replacement part can solve the problem.
Compare system replacement
An obsolete cassette combined with an ageing shared outdoor unit, unavailable controls or repeated major faults can make replacement more economical.
We explain what failed, what remains serviceable and the cost boundary before work proceeds.
Useful repair references
Use the matching system, brand or component page to narrow the next step before booking.
Related repair paths
- Cassette drain pump repair
- Cassette float switch repair
- Cassette indoor fan motor repair
- Cassette indoor PCB repair
- Cassette wired controller repair
- Ceiling cassette aircon repair or replacement
- Carrier cassette repair
- Fujitsu cassette repair
- Gree cassette repair
- Hitachi cassette repair
- LG cassette repair
- Midea cassette repair
- Mitsubishi Electric cassette repair
- Mitsubishi Heavy Industries cassette repair
- Samsung cassette repair
- Toshiba cassette repair
Workmanship warranty
We stand behind the repair we carry out, and we are straight about the part of the cover we do not set ourselves.
Labour
30-day labour warranty. If the same fault returns from the repair we did, we come back and the labour is on us, with no second diagnosis fee.
Parts
Parts follow whatever warranty the distributor sets for that component, so the term varies by part. We tell you the coverage before you approve the quote.
Frequently asked questions about Ceiling cassette aircon repair in Singapore
Do you repair all cassette brands?
Is a cassette error code enough to order a part?
What should I send before a cassette repair visit?
When should a cassette system be replaced instead?
We cover all of Singapore. Find aircon services in your area.
Ready to get started?
Tell us what’s going on. Symptoms, setup, photos, anything we should know. We’ll assess and come back with the right next step.