Hi, new to the group and looking for a bit of advice on the plumbing in an elddis autoquest 140 2011 model. The pump seems to come on during the night and I am 99% sure I don't have any leaks in the van. I have recently replaced the pump with a new whale latest model which was a straight swap. When I look at the clear glass filter after the pump stops running, I can see water dripping back through it heading back towards the storage tank. Is there a non return valve fitted somewhere between the pump and the storage tank that could be faulty? Or any other suggestions that could be causing this? Any help would be appreciated.