Swimming Pool Pump Troubleshooting Guide

 • Phase loss (voltage <200V)

 • Failed start capacitor (capacitance drop >20%)

 • Impeller mechanical lock

① Test input voltage with multimeter (balanced 380V±5%)

② Measure capacitor with LCR meter (refer to nameplate value)

③ Rotate shaft manually; if resistance >2N·m, disassemble to clean impeller

 • Bearing wear (vibration >4.5mm/s)

 • Dry running mechanical seal

 • Loose base bolts (torque <25N·m)

 • Cavitation (NPSH margin insufficient)

① Locate noise source with vibration analyzer

② Replace bearings with SKF 6205-2RS (60% grease fill)

③ Inject hydrodynamic lubricant (e.g., Pacer Pool Lube)

 • Inlet/outlet differential pressure >15psi

 • Motor current <70% rated value

 • Impeller erosion (vane thickness <50% original)

 • Clogged strainer basket (ΔP >5psi)

 • Pipe diameter reduction (<80% pump size)

① Measure impeller dimensions per ANSI/HI 1.1

② Inspect pipe elbows with borescope

③ Verify system flow using Q=πD²/4√(2gH)

 • Shaft seal weepage (>3 drops/min)

 • Casting defects (revealed in 30psi pressure test)

 • Replace mechanical seal (John Crane Type 152)

 • Apply metal-filled epoxy for casing repair (cure >24h)

 • Motor temperature rise >80℃

 • Insulation resistance <1MΩ (500V megger test)

① Clean cooling fins (air pressure ≤0.3MPa)

② Check winding balance (>10% imbalance requires rewinding)

③ Adjust VFD carrier frequency (recommended 4kHz)

 • Winterize with 25% antifreeze solution

 • VFD pumps: Avoid operation below 30% rated speed