I really appreciate how honest and efficient this company is. They identified the problem quickly and fixed it without unnecessary charges. I would definitely recommend them!
M
Matthew Lim
Aircon PCB Repair in Singapore
The PCB controls everything — compressor startup, fan speed, sensor readings, and error protection. When it fails, the unit may not start, throw error codes, or behave erratically. We diagnose whether the fault is the board itself or a downstream component before recommending a replacement.
How we approach PCB issues
Read the error codes first
Error codes are the fastest path to the fault. We read and interpret the codes before opening the unit or testing components.
Check sensors before blaming the board
A failed thermistor or pressure switch can cause the same symptoms as a board fault — but costs a fraction to replace. We check downstream first.
We tell you when a new unit makes more sense
If the board is discontinued or the cost is too close to a new system, we tell you. No point spending on a board when the rest of the unit is end-of-life.
Signs of a PCB problem
These symptoms suggest a control board issue. Some are caused by the PCB itself; others are caused by failed sensors or components that the PCB is reading incorrectly.
- Unit does not respond to the remote control at all
- Error code on the display that does not clear after reset
- Unit turns on and off repeatedly without reaching temperature
- Compressor or fan not receiving a start signal
- Flickering LED display or erratic mode switching
- Burning smell from the indoor or outdoor unit casing
How PCB diagnosis works
We test the board outputs, sensor inputs, and power supply to isolate the fault. A board replacement is only recommended when the board itself has failed.
1. Error code reading
We read any stored or flashing error codes to narrow down which circuit or sensor the board is flagging. Error codes are the fastest route to the fault area.
2. Board output checks
We test whether the board is sending the correct signals to the compressor, fan motors, and reversing valve. A missing output confirms a board-side fault.
3. Sensor and input checks
We test temperature sensors, pressure switches, and float switches to confirm whether the board is receiving correct input. A failed sensor can mimic a board fault.
4. Visual inspection
We inspect the board for burned components, swollen capacitors, corroded traces, or damaged connectors. Some board faults are visible before testing.
5. Repair or replacement
If the fault is a sensor or relay, we replace the failed component. If the board itself has failed, we source and install a replacement matched to the unit model.
Pricing
Cost depends on whether the fault is a sensor, relay, or the board itself. Board replacement cost varies significantly by brand and model.
- Diagnostic visit covers error code reading, board output, and sensor checks
- Sensor or relay replacement is significantly cheaper than a board swap
- Board cost varies by brand — some models are expensive or discontinued
- No parts are ordered until you agree to the quote
Booking and visit timing
Diagnosis is done on the first visit. Board sourcing time depends on brand availability.
- Diagnostic visit typically completed within an hour
- Sensor or relay replacement can often be done on the same visit
- Common board models may be available within a few days
- Discontinued boards may take longer or require a compatible substitute
Indoor vs outdoor PCB
Most split systems have a control board in both the indoor and outdoor units. They handle different functions and fail in different ways.
- Indoor PCB — controls fan speed, louver position, remote signal, and display
- Outdoor PCB — controls compressor startup, reversing valve, and protection circuits
- Indoor board failure → unit does not respond or modes switch erratically
- Outdoor board failure → compressor does not start or trips on protection
- Indoor boards are generally easier and cheaper to source
- Outdoor boards handle higher power loads and fail more often from surge damage
Common PCB faults
These are the board-level faults we see most often in residential systems in Singapore.
- Blown relay — compressor or fan receives no power from the board
- Burned trace or component — visible damage from power surge or moisture
- Failed sensor input — board reads incorrect temperature and behaves erratically
- Capacitor failure on board — board resets or loses memory
- Communication fault — indoor and outdoor boards not syncing
When board replacement may not be worth it
Some boards are expensive or hard to source. For older or discontinued models, the replacement cost may approach the price of a new unit.
- Board is discontinued and no compatible substitute exists
- Replacement board cost exceeds half the price of a new unit
- Unit has multiple faults alongside the board failure
- Unit is older than ten years and other components are wearing
What customers say
Highly professional and efficient service! The technicians arrived on time, performed a thorough cleaning, and fixed my aircon issue. Honest pricing, no hidden charges.
I
Irwan Abu Samah
Initially engaged another company to look into the issue with our aircon but was quoted a much higher price. Snowflake clearly explained the issue and what needs to be done, and recommended possible solutions based on their expertise.
R
Rafidah B
Snowflake clearly explained the cause of the issue and what needs to be done, recommended possible solutions based on what is best for the customer.
S
SaifudinDxdin
PCB repair FAQ
Related reading
Error codes or unit not responding?
Share the error code or describe the behaviour. We will confirm whether a diagnostic visit is the right next step.
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