into cylinder in 10mm pipes, this goes off to a airjec, seperate from existing vent, banging pipes full of air,vent rads all ok , 10 mins later, immediately drawing in air, banging again, I know it`s bad pipework config, it wasn`t doing it 12 months ago, but then again it has been drained recently. I`m a plumber and so-so heating engineer. Thanks for help.
Back boiler, doin me ead in.
- Thread starter billybishbosh
- Start date
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Drain,repipe, powerflush,inhibitor, job sorted
and honest too. can you post a drawing or photo...I know I can`t Not realy cos I haven`t a clue how to. I imagine I need to move the cold feed possibly tie it into vent from BBU. There must have been probs before because there is a second vent in 10mm coming off flow where it enters cylinder this goes to airjec then up to f&e tank, thought it was strange having two vents. Would anyone agree about moving cold feed? pump is downstairs in fekkin fireplace, that`s handy. Cheers.
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check pump/bleed pump and check speed setting
some wally`s seem to always leave them on 3 no matter the system
some wally`s seem to always leave them on 3 no matter the system
It`s been fine for yonks, just started being a pain,pump is fine it`s drawing in air somehow that`s why i mentioned repositioning cold feed.
sounds like an old FEP system....seen quite a few piped with 10mm revolvers.
Pump is on flow, what`s the point about high limit stat? thanks.
The criteria I would always apply , before combining a cold feed & vent , is has the boiler got a high limit stat .
In an overheat (fault ) situation , boiling water / pressure is relieved via the open vent pipe , the coldfeed stops (in theory ) the boiler boiling dry , with a combined cold feed & vent e.g 1 pipe this is unlikely to happen , there fore a high limit stat / over heat stat , shuts boiler down .
In an overheat (fault ) situation , boiling water / pressure is relieved via the open vent pipe , the coldfeed stops (in theory ) the boiler boiling dry , with a combined cold feed & vent e.g 1 pipe this is unlikely to happen , there fore a high limit stat / over heat stat , shuts boiler down .
Sorry to sound thick but all boilers have an overheat stat for this don`t they?
No , depends on age of boiler , alot of the older boilers did not have overheat stats , older Baxi back boilers for example .
So you might be advised to check this out ?? some boiler manuf ' used to supply overheat kits for there boilers so as they could be used on sealed systems off the top of my head , Halstead Bentleys was one e.c .t .
So you might be advised to check this out ?? some boiler manuf ' used to supply overheat kits for there boilers so as they could be used on sealed systems off the top of my head , Halstead Bentleys was one e.c .t .
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