R
racdan
I have recently had a new Oso mains pressure tank installed.Since the installation i am getting a dreadful humming in the cold feed pipe when opening or closing taps or using toilets.It can be intermittent but normally happens a few times after using a tap.The Plumber who installed the new tank has asured me it can not be anything to do with the tank as he has closed the stop tap on the cold feed as it enters the tank and the humming still continues which is true.He says it must be main stop tap,ballvalve on toilets or washers on taps.We have already tried washing mashine and dishwasher and ruled these out.He is coming tomorrow to replace main stop tap which he thinks could be the problem.Any advice would be greateful as it is driving me to distraction!!