the potterton envoy i know ae on open systems maybe itsa sealed system if not what gary says checkin thecylinder cupboar for a silver loop with sme sort of valve on
shauny
July 2007
you should find a silver flexi pipe connected between the mains and one of the heating pipes, on one end of this pipe will be a balafix isolating valve, if you open this valve slowly it will repressurise the system, normallly found under the sink or below the boiler.
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