How to Choose the Right Water Pump

A plain-language guide from New Zealand’s pump specialists

Choosing the wrong pump is an expensive mistake. This guide covers the key factors in plain language.

Step 1: Know Your Water Source

Town supply — you may need a pressure booster if mains pressure is too low for showers or an instant hot water system.
Rainwater tank — a surface pump or shallow jet pump, located above ground near the tank.
Bore (well) — bores shallower than 7–8m can use a jet pump. Deeper bores need a submersible pump installed inside the bore casing.
Stream or lake — water quality is the critical issue; filtration and UV treatment are nearly always required.

Step 2: Flow Rate and Head Pressure

Flow rate (litres per minute): a household typically needs 15–25 L/min to supply multiple outlets comfortably. Irrigation systems often need much more.
Head pressure (metres): every metre of vertical lift, pipe bend, and horizontal run reduces available pressure. Your pump must have enough head to deliver adequate pressure at the furthest or highest outlet.

Step 3: Match Pump Type to Application

Household pressure pumps — automatically maintain set pressure; usually combined with a pressure tank.
Bore/submersible pumps — installed inside the bore, must be sized to match bore yield and demand.
Pool and spa pumps — designed for continuous recirculation; size depends on pool volume.
Sewage/effluent pumps — designed to handle solids; never use a standard water pump for sewage.

Still Not Sure?

Call us on 0800 473 414 or visit our stores in Auckland (Rosedale) or Hamilton (Frankton). Tell us your water source, bore depth, number of outlets, and whether you need irrigation — and we will recommend the right pump.