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Hi , check the safety valve on the outside wall from where the he boiler is . fill the boiler to 1.5 bar , run the heating , then see if the pressure goes up to 3 bar.if it does it will empty out the safety valve ( set at 3 bar).come back with the info and I will run through how to fix
hi have done as above and after 5 mins the pressure has raised 1.8 bar
yes it has now raised to 3 bar
Hi . the pressure will increase as the water gets heated. The boiler has an expansion vessel inside ( like a balloon in a !metal casing) this takes up the expanded water. If they vessel goes flat the water has nowhere to expand, and dumps out the safety valve
yes its raised to 3 bar what shall i do now?
Hi ,take the cover off the boiler, on the right hand side(usually)will be a long metal vessel . there will be a nipple on the side like a car tyre valve . unscrew the cap and use a car tyre pump( or very strong bicycle pump) to pump the vessel up to 1.5 bar . this should solve the problem. If it won't fill up/ pressurise then the vessel is broken and will need replacing.quite rare for that to be the case though
cant get my hands on a pump at the moment, do I have to repeat the whole proceedure tomorrow when I get a pump, or can I just pump it up?
Ideally vessel should be pumped up with the pressure down to zero. Release some from a radiator bleed valve if you have to . pump up vessel to 1.5 , then refill boiler to 1.2 bar.
managed to get hold of a pump, bled nearest rad till pressure was at 0, pumped vessel up to 1.5 bar that sent the pressure upto just over 1 bar which then with heating still on started to rise up to over 2 again, bled rad back to 1.2 and switched heating off. pressure has now rested at 1.2 bar, fingers crossed , have set timed heating to come on in morning so hopefully thats resolved it.
Sounds good , nice one .should have sorted it . just watch that the outside safety pipe doesn't drip. When the safety's opened , sometimes they don't quite seal back up again.they get dirt on the washer.
thanks very much
The same problem continues this morning , the heating didnt come on when set on receiver and the pressure was up to 3 bar again , the outside pipe was trickling water out.
Hi ,I am starting to wonder whether the diverter valve is switching to heating and not staying on hot water circuit. This would cause the boiler to overheat and pressure to fly up . either that or the expansion vessel is split inside.
Take the boiler case off . fill up to right pressure. Put the heating on and feel the heating pipes under the boilerboiler(2 bigger ,pipes. The flow should get hot.if not see if the boiler is overheating,may be a bit noisy like a kettle boiling.
Hi done as instructed and both bigger pipes are hot and no noise from boiler?
Pressure is rising straight back up again and it now sounds bit bubbly?
Ok , is the heating getting hot?