on my bolier it says if over 2 call engineer but it is going on 3
If the relief valve doesn't work, it can explode.
Your boiler is either going to explode or blow a line. this is a dangerous situation and you should not go near it . Shut it down and phone your local boiler, furnace repairman Richard
It will explode if the pressure gets too high. There should be a pressure relief valve somewhere on the boiler to prevent the pressure from building to explosion. Hopefully the valve has been checked regularly and is in working order.
You had better call someone soon, with the extra pressure you may pop some safty valves
yes, like the others have said... you need to get this fixed ASAP for the pressure to get over 2 your safety relief valve must not be functioning call a service person and they can bleed off the pressure to a safe level and change the valve