Loud humming noise when hot taps run All aspects of plumbing questions and answers, help, tips and information

[lorna p]

Last week I had a leaky main stopcock replaced, which seems fine but since then when I run hot tap there is a loud buzzing/humming noise coming from the attic. I called the plumber who did the repair and he just said he had no idea what would cause that. Any ideas on how I can fix this?

[stoneyboy]

Hi lornap,
The most likely problem is that when the hot tap is opened the ball valve allows water into the tank which causes ripples on the surface of the water in the tank.
The ripples cause ball valve bounce which creates the hum noise, This problem is generally worse with part 1 valves. Bend the arm of the float valve sideways (about 5deg) and the resultant friction should solve the problem.
Regards S

[lorna p]

I have been wanting to thank you for ages but for some reason couldn't get website to open. Your solution worked, so saved me a plumbers bill - thank you so much!

[stoneyboy]

☺️