Noisy TRV advice please.

[Fastra]

We've had our central heating system installed for 11 months now and all is fine, except for 2 TRV's that persistently make a scretching/hissing noise when turned to a certain level.

Its no big deal really, but it's loud enough to determine when its turned on and off during the day because it wakes you up.

Just reading through a few forums it seems that the constant advice is to make sure they are 2-way valve and placed in the correct postion. I mentioned it to the fitters when they were back recently to look at banging pipes but they just fobbed me off with 'some just do that..'.

Before I get back onto them can I just ask someone to tell me if my valves are 2 way or not.

Heres a pic (I've highlighted the markings on it - and forgive the dust, Mrs Fastra has been ill ):


This particular valve is fine and is placed on the left hand side of the rad, whereas the one in my bedroom is placed on the right hand side of the rad with the markings on the back of it - this one makes a noise. But one thats placed the same as in the pic in another bedroom also makes a racket!

What suspects me to believe they are in the wrong position is that when the system was being installed I asked for one valve to be moved to the other side (for ease of access), which he did straight away using the same valve.


Or course, when you now tell me these are 2-way valves then all my theories are shot to bits...!

[Ricky_M]

They are two way valves, so doesn't really matter which end they are placed.

Check the lockshield valves are open fully.

[Gingerbread Man]

That Drayton TR4 TRV can be put in either direction of flow. You'd be very hard pressed to find a TRV in todays shops that is single direction model.

[Arthur Jackson]

Just because it's a bi-directional valve doesn't mean it'll be silent. The instructions clearly state the reverse flow rate they will tolerate. My plumber pointed this out to me on a system and we had to fit a bypass valve despite there being no reason otherwise.
You could either move the offending valves to the other end of the radiator, or lie them down.

Edited by Arthur Jackson on Saturday 12th March 17:06

[Fastra]

Ricky_M said:

They are two way valves, so doesn't really matter which end they are placed.

Check the lockshield valves are open fully.

Is that the valve on the other side?
Isn't that meant to have been set and balanced - which I doubt it was? Worth doing though - I'll count the turns, so I can put it back if it makes no difference.

Arthur Jackson said:

My plumber pointed this out to me on a system and we had to fit a bypass valve despite there being no reason otherwise.

How much was it to fit a bypass valve?

[Arthur Jackson]

I can't recall, I'm afraid. It was on a Honeywell Y-Plan system, which theoretically has an open port at all times therefore requires no bypass, BUT my plumber showed me the TRV instructions and it does have some quite clear parameters under which the valve can reverse flow. Seems not everyone reads them!!