Excessive noise but only upstairs

[glucke]

Hi,
new to the forum - have looked at old posts but can't find anything relevant to the problem that I have.
As soon as central heating comes on the upstairs radiators start humming. If all upstairs rad valves are closed humming stops leaving downstairs rads quiet.
Opening any rad valve (upstairs) and the noise restarts.
Rads have been bled numerous times - all rads heat up correctly - turning speed down on pump has no effect.
Upstairs manifold changed but this has made no difference.
Boiler and central heating system regularly serviced - the system was fine and then not.
Any suggestions as to what the problem may be would be appreciated - can't turn my telly up any louder to drown out the noise our the neighbours will complain.
Cheers

 

[AWheating]

check the lockshield valves on the upstiars rads, they are normally closed down to almost off to balance the heating system. Open them up abit.

 

[glucke]

Thanks for the advise, will take and look and post the outcome.
cheers

 

[MP plumb]

You say you have a manifold upstairs, it is possible there is air in the pump of the manifold. Have u listened to the pump?

 

[diamondgas]

Hi glucke, :welcome: to the forum

Humming when any radiator is opened you say? Are they old style thermostatic valves by any chance? Most likely not the issue if it's all or any that cause the mumming. More probably something associated with supply to all upstairs. Would you know if a none-return valve has been fitted on that pipe circuit?

 

[glucke]

Hi,
made adjustment to lockshield valves but this unfortunately has made no difference
Cheers

 

[glucke]

Hi,
The manifold has recently been changed but there is no pump on it.
cheers

 

[glucke]

Hi and thanks for the welcome.
Yes humming when any upstairs radiator is opened - downstairs works quietly without issues.
The humming starts the second the heating swithches on.
Thermostatic valves are approx 3 years old and they are bi - directional (if that is the right term). The thermostatic valves are on the rediators at present.
A none-return valve has not been fitted.
Thanks for the help so far
cheers

 

[stevetheplumber]

take any trv heads of and see if that stops it

 

[Dannyparty92]

Hmmm my guess would have been incorrectly adjusted locksheild valves but as that's not the case I don't know :s.

 

[glucke]

No worries,
thanks for trying to help
cheers

 

[glucke]

take any trv heads of and see if that stops it

Trv's are permenantly off but no difference
cheers

 

[galaxy_plumbing]

Hi,
As soon as central heating comes on the upstairs radiators start humming. If all upstairs rad valves are closed humming stops leaving downstairs rads quiet.
Opening any rad valve (upstairs) and the noise restarts.

Trv's are permenantly off but no difference
cheers

sorry, dont get this? di you try to remove trv's heads as Steve asked to do?

 

[glucke]

sorry, dont get this? di you try to remove trv's heads as Steve asked to do?

Hi,
yes trv's have been removed from rads

 

[galaxy_plumbing]

is this happening when you open any valve upstairs?

 

[glucke]

yes opening any valve upstairs

 

[galaxy_plumbing]

were there any changes in heating pipework etc. before symptoms started?

 

[glucke]

no, it was literally a case of one day quiet next day (and forever after) noisy

 

[galaxy_plumbing]

what happens if you shut downstairs rads and open upstairs?

 

[bewsh]

sounds like the water is being restricted some where.Have you checked the TRV pins aren't jammed?