DHW diaphragm has most probaly split. An easy job to replace if it is
Mr A
November 2007
Most proably your diverter valve diaphram has split. They have a plunger on them you can lift with a small screwdriver which should tell you if it's this.
Steve
November 2007
I can answer this question...
my radiators are all working, but cannot get any hot water out of taps?
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