Noisy Check Valve

[grstafford]

Noisy Check Valve.

I've just installed a check valve (sprung loaded) and it stops the unwanted gravity feed to a bedroom radiator but it is noisy.

Will it settled down? The system has just been refilled and there maybe some air to be bled out and I haven't put the inhibitor in yet in case I need to drain the system again.

Questions,

Will the valve get quieter with time & the added inhibitor?
Is there another type of valve (other than sprung loaded) that will do the trick?

Thanks,

 

[ChrisR]

What sort of noise? They'e inclined to "moan" as the piston part vibrates.
You only need a single check valve of course, so if you've used a double get inside and remove one section. Also you could knobble the spring (heat it up) which will weaken it, but I expect it'll still do the job.

Swing check valves don't moan and are normally used for that job. Needs adaptors, see site for sizes:
http://www.bes.ltd.uk/products/graphics/7518.gif

 

[grstafford]

A hissing noise as the water is pumped passed the spring diaphram. This is amplified in a nearby bedroom radiator.
I guess you can't mount a swing check valve to stop upwards gravity unless you create a dog leg in the piping so the valve in the right way up. Maybe the pump is not powerful enough?

 

[ChrisR]

They can go horizontally too.
But I'd try spring knobbling as you already have a valve.

 

[grstafford]

Thanks for the info, I'll drain the system again! and nobble the spring.

 

[bab]

what speeds the pump on. will it turn down? if at a slower speed all the rad's work ok it will help with the noise. Alternativley try cranking the locksheilds on the rads the check valve supply right down to reduce the flow through the check.

 

[Nige F]

you don`t need/want a spring valve for anti grav....a proper anti grav valve fitted vertically will be the thing .......if you`ve got a vert sect. of pipe and they still make them

 

[doitall]

I would want to know much more about the system, before fitting any valve.

Is the radiator designed to get hot by gravity (heat sink).
What controls are on the heating circuit, if any.
What boiler is it.
Any restriction on the pump will create noise.
An auto by-pass will cure 90% of the problem.

 

[grstafford]

A bit more information for you all.

I made the problem initially for myself I guess by combining the return flow from the Underfloor Heating (UFH) & the return from the normal radiators at a point where the rads return comes down from the first floor.
Everything is pumped. The UFH is designed to operate at times totally independant of all else. So when the UFH is on and the Rads off the return gravity feeds up to the first floor up the rads return. I cannot put a separate return into the boiler because I've laid a new kitchen floor. So an antigravity feed valve I guess is required, this is where we started with the noise. The noise is much less now that I've weakened the spring but I feel that the resistance is still too much and hot water is slow to come down from the first floor.