Bar pressure

[rutterkyn]

Hello everyone
I have got a Vaillant turbomax combi boiler, Its a good 12 years old and i have just noticed that when the heating is on the bar pressure goes right off the scale. When the boiler is left off overnight the bar pressure is at 1.5 which i think is about right. With the pressure going so high is it safe to use?
Many Thanks
Darren

 

[GQuigley67]

how high are we talking ? should go up to about 2.5-3 bar max

 

[wnjswozo]

expansion vessel needs recharging/ or replacing

 

[villa_tom]

expansion vessel needs recharging/ or replacing

Would also agree with this

 

[rutterkyn]

hi Quigly
It goes past 4 and i think it would carry on going if i didnt shut the heating off

 

[Gray0689]

hi Quigly
It goes past 4 and i think it would carry on going if i didnt shut the heating off

If does sound like your expansion vessel but you got a problem as sounds like no pressure relief valve is fitted as should be discharging at 3 bar get a plumber to check it out

 

[GQuigley67]

that was my point as it should have been discharging from PRV, very dangerous DO NOT use this until sorted