Boiler won’t pressurise and overheating

[Scott Laing]

Got a Worcester green star 28i junior that was blowing off, replaced PRV now it won’t pressurise at all, just fills for a few minutes then blows out the PRV, heating and hot water still work if system not over filled. If bypass is shut boiler overheats and cuts out, thinking it’s the heat exchanger that’s blocked but very limited access to boiler so would rather advice before I start destroying the kitchen to get into it

 

[Deleted member 120897]

What pressure are you filling it to? Could be expansion related issue, as for anything else removing the cover would be giving gas related advice, as removing the cover on that boiler forms part of the combustion circuit and needs checking correctly afterwards.

 

[Timmy D]

Could be Rubbish blocking the pressure gauge and you’re actually over filling it.