Most pump failures announce themselves weeks in advance: a slow leak at a seal, a pressure vessel losing its air charge, a filter quietly strangling flow. A short seasonal inspection catches nearly all of them while they are still cheap. This is the routine.
Every three months
- Check the pressure vessel's air charge. With the pump off and system drained, the vessel should hold roughly 0.2 bar below the pump's cut-in pressure. A waterlogged vessel is the number one cause of short-cycling.
- Inspect seals and glands. A weeping mechanical seal is a five-minute fix; a seized one is a new pump. Look for mineral traces around the shaft.
- Clean strainers and foot valves. A clogged inlet makes the pump work harder and starves it of water at the same time.
- Listen. New rattles, grinding or humming that was not there before is the pump talking to you. Investigate before it becomes a shout.
Every six months
- Verify dry-run protection. Trip the float or pressure cut-off deliberately and confirm the pump stops. This single test prevents the most destructive failure a pump can have.
- Check electrical connections. Tighten terminals, look for heat discolouration, confirm the motor's draw is within its nameplate range.
Once a year
- Winterise exposed installations. Drain surface pumps and pipes that can freeze; a cracked casing is unrepairable.
- Review performance. Time how long the pump takes to fill a known volume or reach cut-out. Rising times mean wear or restrictions, so find the cause early.
When to call a professional
Motor faults, repeated dry-run trips, or a submersible that has stopped delivering: stop running it and call service. Pumps are honest machines. They almost always warn you, if you spend twenty minutes a season listening.