central heating high pitched whine

[gb1966]

Hi wonder if anyone can help when i switch heating on and rooms get
to temp i start to get a high pitched whine from boiler one of two things stop
this 1 turning hot water tap on stops the whine and 2 one of the radiators being turned fully up stops it , turning the radiator up seems to be the strange thing as its a specific radiator that only takes noise away which is on our top landing of the the house
Here is what i have tried so far
bled all radiators
took said radiator off and flushed out
changed thermostatic valve on radiator
bled tank on bolier which seemed to have a lot of air in it
and drained system 3 times
All of the above still doesnt stop the whine when valve on said radiator is set at anything
but high all other radiators can be set at different levels
I have an old boiler but has been working great for past 12 years that i have been in house its had the usual things replaced over years such as flow switches and fan, thermostats etc but cant get to botttom of this its a vokera 20/80rs flomatic

Thanks
Gary

 

[footprints]

Does sound like it might be a thermostatic valve, most new ones can go either end, but many old and possibly a few odd new ones are directional.



Look on the valve body for a direction marker and see if the direction of flow is correct, also might be the lock shield valve if it happens when the thermostatic valve head is removed and the valve is the right way around, try a 1/4 turn either way and if no improvement set back the same as before.

 

[hanns21]

U

 

[hanns21]

It's

 

[jeff the gasman]

If you lived next door to me I would have told you not to worry.
It would have been my missus!
Jeff