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Two approaches
- Submersible pump + switched tap: pump sits in the tank; a switch on the tap turns it on. Simple and cheap, good for one cold tap.
- Diaphragm pump with pressure switch: pump keeps the lines pressurised and starts automatically when you open any tap. Necessary for multiple outlets, a shower or a water heater.
What to look for
- Flow (GPM or L/min) sized to your outlets.
- Pressure switch setting (psi) – match to your fittings and any water heater's requirements.
- Self-priming and dry-run protection.
- Noise: rubber mounting feet and flexible hose connections help.
- Strainer on the inlet to protect the pump.
A reference model
Shurflo Revolution 4008
Best for: Pressurised hot-and-cold systems with several outlets.
- Flow
- 3.0 GPM (4008-101-E65)
- Pressure switch
- 55 psi
- Type
- 12 V diaphragm, by-pass
- Diaphragm pumps pulse – an accumulator smooths flow
- Overkill for a single cold tap
Specs: manufacturer page, checked 2026-11-14. Based on manufacturer specs and public reviews – not a hands-on test.
Seaflo and other Shurflo models offer lower-flow and lower-cost alternatives for simpler systems.
Installation & winter
Mount the pump on a solid surface with rubber feet, fit an inline strainer, fuse the 12 V supply, and plan drain points: frozen water cracks pumps and fittings. If you travel in sub-zero weather, drain the system or keep the van heated.
Frequently asked questions
What flow rate do I need for a van water pump?
For a single kitchen tap, a modest flow is plenty. If you run a shower and a water heater, look at around 3 GPM-class pumps. More flow also means emptying a small tank faster.
Do I need an accumulator tank?
It's optional but helpful. An accumulator smooths the pulsing of diaphragm pumps and reduces how often the pump cycles, which makes it quieter.
Submersible or diaphragm pump?
Submersible pumps are simple and cheap, often used with a tap micro-switch. Diaphragm pumps with a pressure switch are self-priming and work like home plumbing. Most full builds use a diaphragm pump.
Spotted an outdated spec? Tell us.