the central heating is ok, but turn on hot tap and after about 20 seconds boiler stops, and then starts again, the water is not hot, could this be a blocked domestic heat exchanger,? and if so how do i de-scale it, or buy a new one,,,cheers for any help

Geoff Barwick, October 2006

if you descale it yourself you have to remove it. or get it powerflushed in which it can be done in the boiler

hi-spec plumbing, October 2006