when using the water on my 1998 abbey 216gts vogue,when using the hot or cold water,the external pump seems to run for a very long time before cutting out,there are no leaks and the water runs fine hot and cold ????
It will probably have a pressure switch on the inside of the van where the inlet is, this may need adjusting so the pump switches off at a lower pressure, this can happen when running on battery as the volts are lower and the pump runs slower.
look for a small lump of plastic connected to the water pipe that also has wires coming from it, it will have an adjuster, either a knob or a screw, unscrew a little, maybe half a turn and try the water again, if adjusted too much the pump will constantly cut in and out.
If it's a leak then the system would be unable to re-pressurise therefore the pump would continue to run which the symptom points to being more likely that the pressure switch needs re-adjusting. When the pressure switch is correctly set up, the cold water will take about 3 seconds to switch off and the hot water a little longer due to the time it takes to replenished the water in the hot water tank.
Try adjusting the pressure switch first and if that doesn't solve the problem then the fault could be a very tiny seal fault such as a worn 'O' ring at the water pump connector or directly behind the inlet port.
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