Prevent Hot water running back?

[BadgerBalls]

Is it conceivable to put in non return valves to prevent the hot water running back to the Truma water heater, I changed the red non return valve on the Truma but am scepticle if it is the whole problem. Are can you fit in non return valves and where would you put them Truma end or tap end?

 

[Damian]

If you are talking about the red connector on the heater with a clear plastic tube coming from it, that is NOT a non return valve, it is an over pressure relief valve.
There should be a non return valve fitted in the cold water inlet pipe near the heater, before the drain valve

 

[BadgerBalls]

If you are talking about the red connector on the heater with a clear plastic tube coming from it, that is NOT a non return valve, it is an over pressure relief valve.
There should be a non return valve fitted in the cold water inlet pipe near the heater, before the drain valve

Yep that was a bit of duff gen given to me by my local agent. He reckoned the red valve would cause the problem.
I will now purchase a non return valve.
regards