Boiler noise like vibrating/buzzing

[silvertabbies]

[h=1]Boiler noise like vibrating/buzzing Gloworm Combi Ultracom 38cxl?[/h]Combi boiler works ok but after about half an hour or more it suddenly makes a noise which sounds like vibrating and I can hear the sound also in the radiators. The sound will stop of it's own accord after ten mins or so but sometimes start up again.

I have found if I just turn the hot water tap on for a second it will stop making the noise.

I have bled the radiators twice and no air in them. The system is only two years old and recently serviced.

Any ideas what is wrong? I can't understand why the boiler works fine and just kicks in with that sound after about half an hour - what is triggering that?

• 1 hour ago
• - 4 days left to answer.

 

[SimonJohns]

What you mean 4 days left to answer

Not my problem

 

[vern]

What you mean 4 days left to answer

Not my problem

Lol I know Exactly what it is but ain't telling!
This answer will self destruct!

 

[silvertabbies]

Sorry the '4 days left to answer' line was not intended and got pasted in by mistake = my mistake

All I can add is that TRV valves are fitted to the rads except one.

Boiler noise like vibrating/buzzing Gloworm Combi Ultracom 38cxl?

Combi boiler works ok but after about half an hour or more it suddenly makes a noise which sounds like vibrating and I can hear the sound also in the radiators. The sound will stop of it's own accord after ten mins or so but sometimes start up again.

I have found if I just turn the hot water tap on for a second it will stop making the noise.

I have bled the radiators twice and no air in them. The system is only two years old and recently serviced.

Any ideas what is wrong? I can't understand why the boiler works fine and just kicks in with that sound after about half an hour - what is triggering that?

• 1 hour ago
• - 4 days left to answer.