My Potterton boiler keeps losing pressure and I don't know why

[fireblade]

Could be heat exchanger on boiler losing pressure down the condense pipe had the same thing on a three year old worcester

 

[Billy Bob Bob]

highly unlikely on this boiler i would be checking prv and expansion vessel worth noting on this boiler it has been known for the expansion vessel to crack on its casing but this would cause a very noticeable flood also the valves could be passing pointing the fault back on the system

 

[Brutha]

highly unlikely on this boiler i would be checking prv and expansion vessel worth noting on this boiler it has been known for the expansion vessel to crack on its casing but this would cause a very noticeable flood also the valves could be passing pointing the fault back on the system

I have seen two of these pinholed already.

Turn the boiler off, fill it up and see if anything runs out the condense pipe. If it does you have your culprit.

 

[Billy Bob Bob]

they might if sentinel feroquest is fitted but i myself or any of the heat-team field engineers i know have never seen this happen

 

[Brutha]

Fair enough but it is a British gas installation... Chances are the system wasn't flushed properly, if at all.

I work for BG and see this on their installations. Maybe its something their using and for the most part BG are changing heat exchangers before we have to go to you guys for help!

 

[James Cridland]

You have a leak it's just in a area it's not showing. When you turn valves off all your doing is turning off your flow and return pipwork from boiler

But if I'm turning those valves off, surely the central heating pipes are isolated, and therefore even if there was a leak in those pipes, surely it wouldn't drop in pressure?

 

[cjg]

are the flow and return valves fully off, as some times you think they off but you have to give some that little tiny bit more and some not all (click) into place,

But if I'm turning those valves off, surely the central heating pipes are isolated, and therefore even if there was a leak in those pipes, surely it wouldn't drop in pressure? ( i would say correct) if the guage is in the boiler side,

 

[jimmygplumbheat]

If the leak is inside the boiler then when you shut the valves off the pressure reading is that of the pressure in the boiler. so pipes aren't likely to be the answer. thats why its still saying its losing. more than likely the PRV or expansion chamber. due to the heat in the boiler its difficult to spot minor leaks as they evaporate away. also not a great deal of water is needed to be lost to lose the pressure.