Why Won't My Pump Work?

The first thing to check is the pump itself.

A simple test can be carried out by putting 12v to the pump to check the operation, if the pump does not run, replace the pump or pump assembly. If the pump does run then there is a problem with the system in the caravan.

Which System do I have?

There are two different types of system in most modern caravans:

a) The Pressure Switch System
This system has a pressure switch in the line of the water pipe. It can sense the drop in pressure in the pipe that occurs when a tap is opened.

There are three main types of pressure switch:

• A Whale pressure switch, situated in the pipeline normally close to the water inlet under a bunk or in a cupboard. It is white and has a screw top for adjustment.This is the most common type.
• An integrated Whale pressure switch built into the housing of a Whale watermaster system.
• A pressure switch built into an onboard self priming water pump such as a Sureflow.

b) Microswitch System
This system has individual microswitches in each tap that operate the pump as each tap is opened.

The easiest way to check which system you have is to look underneath the taps. A microswitch system will have wires going up to to the taps where a pressure switch system won’t have.

Common Problems include:-

If you have a Pressure Switch:

• Pressure switch adjustment, (see adjusting the pressure switch)
• 12v problem, interruption of 12v to the pressure switch or pump housing
• Pressure switch failure
• Isolation switch failure

If you have a Microswitch:

• Individual taps not operating water pump, microswitch in tap not working.
• 12v supply problem