help with boiler cutting out

[Steverose1]

My boiler has started to trip, it has been set between 1-1.5bar the pressure rises to 3bar and slightly over. Is this normal? would this make the prv kick in.

It has recently been serviced, but was doing this before the service.
Boiler approx 4-5 yrs old.

Any help would be appreciated.

Thanks Steve

 

[Burnerman]

The PRV should start to lift at 3 bar...check for water at the pipe outside?
A rise in pressure like that suggests that the expansion vessel may need repressurising.
John

 

[mr-crs]

Hi Steve it sounds like your expansion vessel has either lost its charge or has failed,if you feel confident enough you can let the pressure out of the system and open the shrieder valve on the vessel(if you have access to it)
and see if water comes out.If not you can pump it up with a bicycle pump
to around 1 bar/14 psi.if water comes out it needs replacing poss not something you would be able to do,as a tempory fix just drain a radiator then open one side only and dont bleed the air out this will act as an expansion space till your vessel is replaced hope this helps.

 

[Steverose1]

Is it expensive to get the expansion vessel repressurised?

I will have to fire the system up and check the outside pipe.

Thanks for the info

 

[Steverose1]

mr - crs

thanks for the info, I think I should get somebody out to look at it.

Is it expensive or a routine change part?

Cheers Steve

 

[ade2k]

it is quite easy for a experienced boiler engineer to change the quickest way to solve this problem if the ev is failed is to put a expansion vessle on the return pipework to the boiler as you dont need to lift the boiler off the wall.