Mature HDB infrastructure
Bedok North, Bedok South, Chai Chee, and older town-centre blocks can have aged piping routes, drain runs, isolators, and trunking. The flat's fittings can be part of the fault, not just the fan coil.
Usual faults
Leaks and trips that start at the drain, isolator, or trunking, not always the aircon body.
