My Potterton performa 28 is leaking from 2 places and has a pressure of 30 bar , this pressure increases when the heating is on and the hot tap is used ? Does anyone know what the problem is and whether it is expensive to fix ? Or do I need to replace the bolier ?

Mark H, January 2009

the problem maybe that with the pressure too high the filling loop may be passing. release some pressure from the central heating system back down to 1 bar, and then check when heating is on if pressure rises over 3 bar, it maybe that you vessel has gone, this can be sorted by fitting a remote vessel near to the boiler, as sometimes the boiler has to be removed off of the wall to replace the old vessel!

jb, c&j plumbing&heating sheffield, May 2009

1 check the filling loop is not letting any water pass through the valve....disconnect it.....free
2 expansion vessel may have lost its pressure....drain primary system and recharge to 1 bar ...refill system £30
3 expansion vessel diaphragm may be split....replace vessel £200
4 plate leaking from primary to secondary....replace plate heat exchanger...£150

brandon, January 2009