I have an Adria 542UK. It has a submersible whale water pump - in to an external aqua roll. The problem I have is that the pump switches on for just asecond occasionally (every half hour or so) - a real pain during the night! I have adjusted the micro-switch within the van as explained in the tech manual, all to no avail. The taps work fine. Any help? I have to disconnect the water at night at the moment!!