Main Combi 30 HE
My boiler is only about 3 years old. Recently when the heating has been on, a really loud noise has occured.. like a whirring, vibrating thing seemingly in our living room in a pipe going upstairs. It also happens sometimes when the toilet is flushed. Running the hot tap stops it.. but the noise is deafening me and my neighbours.. Have bled the radiators already, any help?

Ali Johnston, November 2010

check ball valve in main cold water tank may be noisey and flushing W C or open cold water will stop it. replace it with part two ball valve. boiler should be ok

k, November 2010

Yes I agree, it sounds like the incoming stop tap needs turning down a little-a half to a whole turn. Then see what happens! If no improvement,then I'm afraid you will have to seek professional help on site.

Reggie, November 2010

Sounds like water hammer rather than a boiler problem, try adjusting the mains stop tap.
Fitting a non-return valve and mini-expansion vessel to the water main often helps.
Best advice, seek a plumber rather than a gasman.

Carefree, November 2010