Question

Hi Tom I have a whale 881 supersub pump when I plug it into the Caravan the pump runs but I can hear a clicking noise when I turn the taps off the pump carries on running could you please advise me on the problem

Answer

This is a problem with the pressure switch that controls the pump. If you have a Whale Watermaster inlet then the screw to adjust the pressure switch is on the back of the inlet fitting. If you have a Truma crystal inlet then the pressure switch, probably our part 105500, will be in the pipework, normally fairly close to the inlet.
To adjust the pressure switch you should first undo the adjusting screw as far as possible without removing it from the threaded hole. Then open one of your cold taps. If the pump starts then there is a problem with the pressure switch and you may need to replace it or dismantle and fit a service kit.
When you open the tap the pump should not start, and then you gradually screw the adjuster clockwise until the pump starts. Close the tap and the pump should stop.
If the pump does not stop then a quarter to half turn anticlockwise should be sufficient.
Operate a tap again a few times to ensure that the pump operates correctly and some minor adjustment may be required at the adjusting screw to prevent the pressure switch 'clicking'.
I hope that this helps.