Dripping after filter cleaning traced to drain-trap seal loss
Aircon case in Central Area, Singapore: post-service issue traced to drain trap lost prime after cleaning sequence after targeted diagnosis checks.
Case details
What client reported
The unit started dripping the day after routine cleaning. Cooling was still strong, but drops formed around the panel edge by late afternoon.
What we found
Because cooling was stable, we prioritized drainage checks before considering refrigerant or major hardware faults.
- Panel and filter were clean with no ice pattern
- Drain line was open and not physically blocked
- Trap section had lost water seal
- Water backed up at the tray during steady operation
The drain trap was left without a proper water seal after cleaning. Without that seal, drainage became unstable and condensate collected until it overflowed at the panel edge.
What we did
No coil or pump replacement needed. We re-primed and reset the trap, confirmed steady discharge, and verified tray level stayed stable.
Dripping stopped and cooling remained normal. The fix was completed without parts replacement.
Timeline
Day 1
Drip started after routine cleaning
Day 1
Performed a controlled drain flow test and confirmed the trap had no standing water seal
Day 1
Drain trap reset and flow stabilized
What we learned
Why leaks after cleaning often come from drainage setup.
- If cooling stays normal but dripping starts after cleaning, drainage should be checked first.
- A missing or weak trap seal can cause tray backup even when the drain pipe is open.
- Restoring drain seal and flow stability can solve the leak without major part replacement.
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