Truma Crystal Maxi water pump

[Swadlingtons]

We encountered a problem at the weekend. When I lifted the pump from the aquaroll to refill, hot water was flowing out of the pump back into the aquaroll. I disconnected the pump connection from the side of the caravan, but hot water continued to flow, now from the connection on the caravan. The only way to stop it was refit the pump and to hold it higher than the level of the hot water tank.
Once the aquaroll was filled, the pump no longer worked. There are 12 volts at the connection.
Is it likely to just be a pump problem, or something more? Any ideas please?
The caravan is a 2006 Sterling. Pump has the two separate electrical pin connections (older type?).

 

[Buckman]

Probably something simple and a cheap repair like a faulty non-return valve. Perhaps if you giver details of your caravan i..e year, brand and model someone with a similar caravan can offer better advice?