Question

I have a 2012 Elddis Avante 574. The water heater (Truma) sometimes will not work on Electric. After checking the consumer unit and then checking the 5 amp fuse on the consumer unit it then works. Do you think its the 12 volt supply that is at fault

Answer

The electric heater on the Truma Ultrastore water heater is reliant at all on the 12 volt supply. You may therefore have a faulty MCB in your consumer unit. Alternatively check the in-line connector in the wire leading to the electric element to make sure that it is properly connected.