as said before if hes qualified why didn't he powerflush the heat exchanger. its no good filling it with preservtives if the problem hasn't been cleaned out to start with.all the time there is air/muck in system it is corroding. you will never move limescale / muck out of system completley by just flushing or beable to use the right cleaning chemicals. did he suggest fitting a combiguard before the boiler mains inlet. that will help your limescale, as fitted to most systems now with bad limescale.
( so hes had a nice little earner, and your'll be no better off by next week )
hi-spec plumbing
January 2007
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