For the last few months there is a sound of running water coming from our pipes. No taps have been left on and there are no signs of leaks inside or outside the house. Where could the noise be coming from? Please help, it's driving me mad!

Ali, January 2009

possibly air in heating system are rads cold at top in places - bleed radiators top up system again if required i.e. closed.
possibly open vent heating system running over into tank, look in loft when happening is water running into small tank? if so check pump.
possibly is leak in other system turn of mains and check when house is quiet and tank not filling does water sound stop and tank level stay the same? are you on a meter does meter turn when all taps off and tank not filling? try these as diagnostic steps

Kenny F, January 2009