here`s a good un

[doitall]

Unidirectional TRVs (no apostrophe!) judder with reverse flow when they are close to closing and the differential pressure is quite high (most other TRVs shut). Those of us who grub around at the boring domestic level know this only too well.

For starters it is not a unidirectional TRV, and most TRVs (no apostrophe!) will judder with reverse flow and not just when they are closing.

The reverse flow hasn't been proven only an I think.

We don't know the make of the valve and that makes a lot off difference.

Finally ask the manufacturers.

 

[doitall]

Since ballski keeps posting pics of antique Myson valves, the data for their new ones.

http://www.myson-htg.co.uk/install/TRVTEC.pdf


INSTALLATION INSTRUCTION
FOR THE MYSON THERMOSTATIC VALVES
Installation:
The Myson Thermostatic Valve allows flow through the valve in either direction. Therefore the valve can be fitted to either end of the radiator without reference to the flow direction of water flow.
It is an industry recommendation that an Automatic By-Pass Valve (a Myson Automatic By-Pass ABV22 is suitable) be fitted between the flow and the return immediately after the pump in systems having Thermostatic Radiator Valves installed. Where a Combination Boiler is installed or the differential pressure exceeds 0.6 bar it is essential that a Myson Automatic By-Pass Valve be fitted.




Thats because they will rattle ballski, ask them yourself as you don't believe me.

 

[Waterworxsw]

dia

hats because they will rattle ballski, ask them yourself as you don't believe me.

Quick question, do all makes of TRV rattle?

AL

 

[doitall]

dia

hats because they will rattle ballski, ask them yourself as you don't believe me.

Quick question, do all makes of TRV rattle?

AL

Most will under the right conditions.

As I have said, pick your favorite make and ask the maker, you don't have to take my word for it.

Just post their reply, in the meantime why do all manufacturers make a big issue about pressure differentials in their technical jargon.

 

[chrishutt]

DIA, I regularly flush out heating systems using mains water pressure, flowing alternately in each direction. I control the flow through the rads with the TRVs, so the differential pressure could be as high as 2 bar! The TRVs are fine when the flow is in the direction indicated on the valve body but they can judder violently when the flow is against the direction indicated.

 

[doitall]

DIA, I regularly flush out heating systems using mains water pressure, flowing alternately in each direction. I control the flow through the rads with the TRVs, so the differential pressure could be as high as 2 bar! The TRVs are fine when the flow is in the direction indicated on the valve body but they can judder violently when the flow is against the direction indicated.

Most valves can take anything up to 10bar, turning a valve on and off does not simulate a valve slowly closing, even so I bet it bangs if you shut it off quick.

What happens with bi-directional valves.

And I'll say the same to you Chris ask the manufacturer and post their reply

 

[clf-gas]

DIA Enough said on how a TRV will work, they in the Know understand your point.
Those not in the know (like the the cowboy/ imposter rip off merchant/ talk google water sales men) will insist on flow / RETURN! / Pump... Blar di blar.... Change the feckin TRV.....

 

[doitall]

Good news mod8 the thread is going nowhere without the information I asked for.

The OP can ask the manufacturer as can anyone else.

Best to leave it locked,