TRVs banging

[Taylortwocities]

I have problems with TRVs on my CH system.

From time to time the systems starts making loud vibrating noises. This turns out to be coming from one of the TRVs. A slight adjustment to the valve will stop the noise. This does not happen from one TRV, it can be from any one of them.

I've tried changing the pump adjustment but its still the same. System is free or air, as far as I can tell as all rads are hot from top to bottom.

Grateful for your advice.

 

[Andy165]

Is trv bi-directional ? If not it is on the ch return pipe instead of the ch flow pipe. swop the lockshield over . Alternatively you have purchased a cheap brand that is not working too well . Try turning it around i.e. instead of the trv valve & head pointing upwards, pointing to the side, that usually sorts it out

 

[Andy165]

You have got a bi-pass valve on the system i presume

 

[Kristoflampie]

bet they are danfoss............ mine infuriate me , its just as they are trying to shut down, Ive tryed swopping them every which way..... nae difference

 

[Andy165]

Is that the brand with the flow direction arrow underneath the trv head ? Plumbcenter ***** Forgot about that one, they were crap If it is, take the trv head off , with the ch on, feel both rad. pipes to see which gets hot first and turn the valve to point in the direction of the flow. Sorted

 

[Taylortwocities]

Thanks for the prompt replies!

The ones we fitted have 'Tower' written on the top and look like this:

Untitled

• Taylortwocities
• 6 Sep 2008
• 1

They were here when we moved in. The flow arrow is on the metal elbow under the TRV. On this one (this one of the valves that makes the noise) the arrow points downwards (ie away from the rad).

Can't turn some of them round as (like this one) the TRV would stick out past the wall.

If I read the responses above right, the solution would be to change the TRVs to a make that works on either flow & return. Which make is best? Or is there another solution.

 

[twgas]

I would do as earlier post, turn off all TRVs - turn on heating - go round turning rads on, one at a time and feel the pipes as you do so - the first pipe to get hot is the flow - any that are not on the flow need to be swapped with lockshields.