Diagnosis and Treatment of Insufficient and Fluctuating Water Pressure
Water pressure problems are the most common hotel water supply faults, manifesting as low terminal water pressure or pressure fluctuation during peak demand periods. Diagnostic methods: (1) Check municipal incoming pressure (normally should not be lower than 0.20MPa); when pressure is low, tank supply must be activated; (2) Check the variable-frequency water supply system: verify whether the VFD frequency output has reached 50Hz full-frequency operation while still failing to meet the pressure setpoint; if at full frequency, verify whether pump selection is undersized; if not at full frequency, check whether the pressure sensor signal is abnormal; (3) Check the pipe network section by section: close branch valves for isolation testing to locate leaks or blockages; (4) Check pressure reducing valves: whether downstream pressure deviates from the setpoint and whether the strainer is clogged. Solutions: When pump selection is insufficient, increase the number of operating pumps or replace with higher-flow pumps; when the sensor fails, replace the pressure sensor; for PRV problems, clean the strainer or replace the valve cartridge assembly.
Drainage Blockage and Odor Remediation
Drainage blockage and odor are among the most common complaint issues in hotels. Causes and treatment of blockages: (1) Bathroom drainage: hair clogging floor drains and washbasin traps; regularly clean hair collectors, and use drain-cleaning machines or chemical drain openers in severe cases; (2) Kitchen drainage: grease solidification clogging pipes; perform regular hot water flushing (water temperature above 60℃) or biological enzyme cleaning, with mechanical pipe cleaning when necessary; (3) Main drainage pipe blockage: use high-pressure jetting trucks (pressure 150-200bar) or pipe inspection cameras to locate. Odor remediation: (4) Check the water seal depth of floor drains and sanitary fixtures (should not be less than 50mm); replace with deep-seal floor drains if insufficient; (5) Check whether the venting system is unobstructed and whether the dedicated vent stack is blocked; (6) Check whether an energy dissipation device is installed at the bottom bend of the drainage stack to prevent positive-pressure splashing. Establishing a regular pipe cleaning regime (kitchen hot water flushing once per month, guest room drain cleaning once per quarter) can reduce the blockage rate by 80%.
Hot Water Temperature Below Target and Slow Hot Water Delivery
Common hot water system problems include hot water temperature failing to reach the setpoint, excessively long waiting time for hot water, and fluctuating hot/cold water temperature. Cause analysis and solutions: (1) Insufficient heat source capacity: verify whether boiler/heat pump heating capacity meets peak-hour hot water demand; if insufficient, increase capacity or add heat pumps; (2) Heat exchanger scaling: scaling on the water side of plate heat exchangers reduces heat transfer efficiency; perform regular chemical cleaning (circulating cleaning with citric acid or sulfamic acid solution); (3) Circulation system design defects: reverse-return hydraulic imbalance causes insufficient circulation flow in some risers; install dynamic balancing valves or convert to reverse-return piping; (4) Excessive branch pipe length without heat tracing: when the distance from riser to point of use exceeds 5m, branch pipe heat tracing must be installed; self-regulating electric heat tracing cable (power consumption 20W/m) is recommended; (5) Thermostatic mixing valve failure: failure of the thermostatic mixing valve temperature control element causes outlet temperature fluctuation; replace the cartridge or the entire valve.
Water Quality Abnormalities and Secondary Pollution Prevention
The safety of hotel domestic drinking water quality is a red line in operations. Common water quality problems and countermeasures: (1) Yellow water (excess iron): caused by pipe corrosion, concentrated in the first water use period in the morning. Solution: flush pipes (run water for 2-3min); if persistent, replace pipe material (galvanized steel pipe to stainless steel pipe or PPR pipe); (2) Total bacteria count exceeding standard: tank not cleaned and disinfected regularly or improper disinfection method. Strictly clean and disinfect once per quarter, and use UV disinfection units or sodium hypochlorite dosing devices for continuous disinfection; (3) Odor: missing insect screen on tank vent or improper pipe connections; check and repair the insect screen, and investigate whether non-potable water pipes are mistakenly cross-connected with domestic water supply pipes. According to the Standards for Drinking Water Quality GB 5749-2022, hotels should conduct full-item water quality testing at least twice per year (42 routine items + non-routine items), with test results archived for reference.