bleeding not as easy as it seems

[chefnotplumber]

I have just bled one of the rads in my house because it was cold at the top . I bled with the key and let the air out slowly (heating was still on ) . Since doing that a high pitched humming noise came from the pipes around the boiler unit. The rad is right next to the boiler and i have turned the heating off ( now in cold house with grumpy wife).The boiler looks old not sure of age the only thing writen on it is , Potterton netaheat 10-16 mk II F . The boiler had been checked about april 2006 .

 

[gavinda]

not that this'll help with the noise... but id start budgeting for a new boiler

 

[uknokianut]

Try checking the expansion tank in the loft , the ball valve could be stuck, maybe theres no water in system .

 

[chefnotplumber]

The rest of the water system seems to be fine.Is there some other pressure valve on the way to the radiator ?

 

[ChrisR]

Did you/can you get water out of all the rads? And the vent by the hot water cylinder? Do it with the boiler OFF.

Your boiler is early 80's.

 

[chefnotplumber]

I only bled the one rad I can get water out of all of them . from the boiler there are about five pipes all coming from the same side . one of the pipes has a red box called a super selector could this need adjusting?

 

[ChrisR]

If it's a roundy sort of box which hums a bit that's the pump!
No obvious reson why your boiler should have stopped following simple bleeding of a rad, time to call someone in perhaps.

 

[chefnotplumber]

could it be the pump then thats humming loudly? It was very hot before I turned the boiler off.