What blocks ac condensate drain unblocks in Kwun Tong

Algae build-up in flexible drain pipe (humid HK climate)

Dust + lint from AC filter blowing into drain

Pipe slope incorrect causing water pooling

Outdoor pipe end blocked by debris

Kwun Tong building patterns we see

Industrial-spec pipes (smaller than residential standard) overloaded by post-conversion residential use

Rooftop drainage clogs from old industrial venting

Subdivided unit kitchens with shared mains

Older industrial-spec sewage backup during heavy rain

Method Compressed-air blow-through → vinegar flush → check pipe slope → test 10-min AC run for re-pooling.

Kwun Tong-specific knowledge. Kwun Tong industrial-converted-residential buildings have unusual drain configurations — original commercial-spec pipes never designed for residential volume. We see weekly calls for blocks in converted 1970s industrial-now-residential buildings around Hung To Road / How Ming Street.
Service-specific method. AC dripping water inside / from outdoor unit = clogged condensate drain in 95% of cases. Blockage is dust + algae build-up at the narrow flexible drain pipe. 10-15 min job. Most-undercharged HK service.
Fixed price quoted on phone. No 'we'll see when we get there' surprises. From HKD 250.
7-day re-block guarantee. Same drain re-blocks within 7 days, we return free.
Receipt + tax invoice always. For tenant-landlord reimbursement or building AP.