I switched from Truma to Whale after 2 Truma failures. So I agree with Buckman.Not sure about the part to which you refer, but with a previous caravan after suffering 3 Truma water pumps breaking down on us, we changed it for a Whale pump and no more issues. More recently we had newer caravans with the complete Whale system fitted and we had no issues with the system in over 9 years.