Boiler Problems

[Ric.ror]

I’ve set my pressure level to 1.5 but after two hours on it has risen to almost three just about to enter the red zone so I’ve turned the heating off
Can I reduce my pressure to 1?
It’s a one bedroom flat btw

[Fitzer]

Bleed water from a radiator or the drain down valve on the system.

[Atheist]

You could try reducing the pressure to 1 and see how it goes. If the pressure rises again close to 3 then it might indicate an expansion vessel problem. The problem could be that the expansion vessel needs pressurising (with a car foot pump) or replacing. Either way it's probably a bit difficult for a home repair and you would need to get an engineer to check it out.
Do you often need to top up the system water to increase the pressure?

[Atheist]

Sorry, I forgot to say what Fitzer said, i.e. how to reduce the pressure.

[Ric.ror]

No I don’t often need to top up - mostly because I don’t have the heating on all that often certainly not everyday as I’m only in a couple of days - when I’m working by the time I get in it would be after bedtime before the flat warmed up

[Ric.ror]

Sorry - I forgot to thank you for your answers

[The Builder]

Ric....... it's just that water expands when hot. The expansion vessel acts as a cushion to soak up the excess pressure.

If the vessel is punctured or it has lost its pressure charge, then boiler pressure will rise up to the red zone and blow water out of the system (to outside) to relieve the pressure.

I'm afraid there is nothing you can do except get the vessel and the pressure relief valve checked.

[johnk]

I have a valve that lets all the pressure go, you will have to try and find yours. Have you left the mains water connected and turned the fill valve off, it only needs a very small leak getting past the valve to pressurise the tank.