Vaillant Boiler Over Run control

[garygvl]

still doesnt answer your question why would a heat only need the pump overrun on hot water (when the hot water is used)

so whats the issue when the boiler doesnt have its overrun (safety wise)

its not a safety issue boilers will lock out on overheat if heat not being dissapated after stat shuts them down. its the long term damage being done to the heat exchangers that is the problem

 

[ShaunCorbs]

would be best but not mandatory on ss hexs as they can take the heat

 

[Leslie1407]

Your missing my point. Your going to spend £99.00 on an RF box when you could just use a cable from the old timer as that cable will go to the 10 way in the airing cupboard and the boiler. The old wiring is now redundant as the rf receiver is now in the airing cupboard?

All the cables between the boiler and the immersion cupboard are all used the engineer tells me. I either place a new cable under the floor back to the boiler just for over run or I use the RF kit i'm told.

 

[garygvl]

its not a safety issue boilers will lock out on overheat if heat not being dissapated after stat shuts them down. its the long term damage being done to the heat exchangers that is the problem

ok shaun could have had a debate

 

[Harvest Fields]

not always

Agreed. But if it has been done properly it will.