When I switched the Truma electric water heater on the fuse blew at the site
connection post (later at home the 30amp garage fuse). This said none of the
inboard fuses/switches for the water heater were thrown - which seemed odd.
All other electrics are fine. In the meantime have switched the control
panel water heater fuse permanently to off and am using the gas for water
heating as and when needed.

Am taking the van to the dealer for service in a couple of months BUT any
ideas why the van fuses at the control panel didnt cut out ? Could the
problem be in the control panel rather than the heater ?