two things, its either the expanssion vessel needing recharged causing the pressure to rise when in use or the main heatexchanger has a hole in it allowing the water and heating sides to mix causing the pressure to rise.
Martin MRH Gas
July 2012
filling loop may be letting water so diaconnect it and cap it and than see
k
July 2012
I can answer this question...
how can i stop my worcester 24i junior from constant pressure rising itself?
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