Question

My Truma heater is so effective it has started heating the cold water as well. The water is VERY hot. How do I rectify this please?

Answer

The answer to this will depend of which type and model Truma heater you have. I will also need to know if the problem is happening during gas operation or electric operation; each operation will have an independent thermostat. If it is an Ultrastore over heating on the electrical side then the thermostat is preset so you would need to replace the complete element, this however is just one scenario.