Will this drain off tail piece leak?

[BobbyBrown]

Hello,

I'm in the process of changing all my radiators which are supplied by pipes which come out horizontally from the wall. I need to add a drain off valve to each radiator as they are drop fed from upstairs.

I've seen this https://www.screwfix.com/p/drayton-...gclsrc=aw.ds&dclid=CO7KwZnC3NgCFY0TGwodxFYA_Q

tail piece from Drayton. Unfortunately if you use a non-Drayton TRV (they don't do any angled versions), the thread on the valve side does not fully screw into other makes lockshield valves.
Before I order a job lot and start fitting them, is it likely to seal properly?

 

[John D v2.0]

the left hand side will be a compression fitting not a tapered/conical. With enough gunk on the olive it might seal, but it isn't the right way. The olive on the "pipe" part needs to be squashed into the gap between the nut on the drain valve and the threaded fitting that you have supplied.

 

[terryplumb]

Re the chrome fitting ,held by your hand in pic , can you take a pic of this ,showing the inside shape of the open end ( where the nut connects ). And did that part come with a nut and olive ? I can't tell if its a compression fitting or just a bsp thread.

 

[BobbyBrown]

To be honest It's probably not the best valve I've shown. It was just one I had knocking around. These are the valves I'll be adding:
https://www.theheatingboutique.co.uk/hb-signature-talus-trv-white-thermostatic-valves-corner.html.

This is the same one from an existing radiator I've just fitted:

So instead of the normal tail I'll be using the Drayton drain off tail.

 

[terryplumb]

This pic is showing a compression joint , if you remove from the " drain off" ,the nut and olive supplied with it ,you are left with a 15 mm " tube" section.this will go straight into the chrome valve ,using the nut and olive that comes with the valve.

 

[BobbyBrown]

Got it, cheers