324 Water & Waste (ATA 38) service difficulty reports for the Boeing 737 (all variants) — 0.1% of all reported difficulties.
Most reported components
- TOILET 49
- UNKNOWN 25
- POTABLE WATER 23
- WATER HEATER 22
- LAVATORY 20
- CIRCUIT BREAKER 11
- VALVE 11
- DRAIN LINE 10
- COMPRESSOR 9
- BLOWER 9
- DRAIN VALVE 8
- DRAIN 8
- FLOAT VALVE 7
- SENSOR 6
- WASTE TANK 6
Report counts reflect fleet size and reporting activity, not relative safety or reliability. Source: FAA Service Difficulty Reporting System (public domain).