hot water fine except for some scale (not a lot) but central heating system noisy like air is trapped in it(gurlgling,popping, 'kettling'?) and takes time for water pressure gauge to rise to 1.5 on boiler.noise quietens down a lot after 15-20 mins sporadic popping and a water trickling type of sound.CH water system cleaned out 7 days ago not power flushed,- system preservative put in air vents fitted in pipes in loft by qualified CH fitter noise did reduce to what it is now(as described above) what can be the problem?

sim, January 2007

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