Noise of running water

[suirs400]

I've just moved into a house with a modern (3 year old) oil-fired central heating system where all-bar-one of the radiators are equipped with thermostatic valves.

The system seems to work very well except that there is a more-or-less constant noise of water running through the system. The noise is most noticeable at each radiator; it goes away when the valve is turned down and gets progressively louder as the valve is turned-up.

I have bled all the radiators that have bleed valves at the top, which means those upstairs. All of the rads downstairs have valves at the bottom and so I assume they don't need bleeding?

Anyone got any bright ideas because my wife is unhappy about either being slightly cold or having the background noise of running water!

Thanks in advance.

[Steve the gas]

Hi,

Sounds like air.
Bleed all rads with CH off, all rads have bleed points.


Hth