Diverter Valve? Hot water but no CH

[pavementpizza]

Sorry, the saga continues...

The system is now losing water every day...so much so the safety device (?) is preventing the boiler from starting. If I add water upto 3 and run it for a few hours (CH) everything is fine but overnight it is dropping to 0. No visible leaks anywhere but then there were none before. If you see my last post you'll see what happened previously.

Any help anyone?

 

[ACOperson]

You will probably find that if theres no water anywhere visible that its going out of the PRV - have a look at the pipe outside under the boiler flue.

Needs new PRV, possibly needs expansion vessel re-charging...

 

[pavementpizza]

There is a pipe outside above the flue (overflow?) which is dripping slightly and it hasn't done this before. I take it this is the cause. How do I recharge the expansion vessel?

 

[ChrisR]

See"Boiler Pressure Problems" in the For Reference section.