Boiler losing/gaining pressure

[jasonjxb]

Good morning. I have a valliant boiler with pressure set at around 1bar. When I flicked the heating on last night the pressure rose to 3bar. Then when the heating went off it dropped down to 0bar.

Any ideas? I have bleed all the rads

Jason

 

[Dannypipe]

When it rose to 3 bar, the Pressure relief valve would have operated, which will have jettisoned hot water out of the house. When it cooled down the pressure will drop to almost nothing and the boiler will lock out.

Call an Gas Safe installer to look at your boiler.