Question

My Aquaroll ran dry, leaving the submersible pump running. Having refilled the aquaroll, the pump now runs continuously even though all taps are closed. What could be the problem. I have checked all the microswitches, and are all OK. Hope you can help.

Answer

If you have microswitches in the taps then it is most likely that one of these has a short circuit, probably the one that was left 'on' when the tank ran dry. You will need to disconnect each microswitch in turn, by disconnecting the wires underneath the sinks, until you identify which switch is at fault.