Adjustable Rad valve tail - have I bought the wrong ones?

[aclivity]

Hi There

first post, looking for a little advice. I have searched but I couldn't find the specific thing that I am looking at.

I'm replacing a rad in one of the bedrooms, the one I bought was a couple of centimetres narrower than the one I was replacing. Not a problem, I thought, as there was some flex in the pipes, and a longer rad tail would bridge any gap.

I bought a pair of these:

today, but I can't see how they can work? The valve nut goes over it fine, and the thread (on the left of this picture) fits into the radiator, but there is no "shoulder" for the tail to tighten up to, so it just goes on turning until it's right into the radiator bit. I'm not explaining this too well ... perhaps a drawing would help:

I can make the one I bought go tight, but the "shoulder" bit is then quite far into the radiator, and I don't think it's really making a decent seal.

Have I bought the wrong thing, or am I using it incorrectly?

Thanks in anticipation

Andy Hill

 

[tonybhoy]

It pushes out mate, the internal part, or you might have to use an Allen key and turn it out. Can't really remember but it's one or the other.


Yeah looking at your pic the thin end moves to reveal a nut on the end of the threaded end, I'm sure it just pushes forward. have a couple in the van but it's a bit too late to go out right now

 

[glasgowgas]

It pushes out mate, the internal part, or you might have to use an Allen key and turn it out. Can't really remember but it's one or the other.


Yeah looking at your pic the thin end moves to reveal a nut on the end of the threaded end, I'm sure it just pushes forward. have a couple in the van but it's a bit too late to go out right now

must be a right rough area where you are Tony, ya sh ee itebag!!!!!!

 

[aclivity]

Thanks for the quick answers ...

I think perhaps I'm not explaining myself too well here - I've taken some pictures to explain what I meant:

Tail partially screwed into rad, all looks well and good:

Then tightened into the rad, it goes in quite far and I'm not confident that there is a seal:

In the second picture, it doesn't seem to actually push up against anything, just reaches the end of the threaded bit. I was under the impression that the PTFE tape was just to protect the thread, not form a seal - something should be in compression to form a seal?

 

[kevplumb]

when you tape them try to get the tape in a cone

like 2 turns right on the end and taper it up

 

[gas_man_gaz]

id use longer tail's cut to size, the telescopic kind are bound to leak over time

 

[aclivity]

option 2 is to get a plumber to move the pipes for me - this would be the "best" solution but money isn't irrelevant (hence DIY'ing). How much would a decent plumber charge for this, if I fit the short valve tails to the Rad, and it's already hung on the wall so only needs the pipework doing? The pipes are 9mm rather than 15mm.

 

[tonybhoy]

must be a right rough area where you are Tony, ya sh ee itebag!!!!!!

Aye very funny sonny I'm sitting here in my pjs in deepest darkest Clarkston

 

[tonybhoy]

option 2 is to get a plumber to move the pipes for me - this would be the "best" solution but money isn't irrelevant (hence DIY'ing). How much would a decent plumber charge for this, if I fit the short valve tails to the Rad, and it's already hung on the wall so only needs the pipework doing? The pipes are 9mm rather than 15mm.

If the pipes are 8MM can you not just pull them over a bit? I've used those rad tails before and never had that problem of them disappearing into ther rad hnowever BES do a different type that are fixed and come in lenghts up to about 50MM but you can join a few of them together to make up any lengh you need. I've also used straight tap adaptors to extend to the pipes.

 

[bathstyle]

id use longer tail's cut to size, the telescopic kind are bound to leak over time

Snap, a much better option

 

[TicklyT]

In the piccies, the problem is the clearance between the tapered threads appears to be a little on the generous side, so the fitting runs too far into the rad before the clearance takes up.

If you can see the thread through the PTFE tape, you need more tape on the fitting.

I would try lots of PTFE tape until you can't see the threads of the fitting, then add some more tape, then wind some PTFE tape over the top of that before trying it in the rad. again.
Sometimes 20 turns of tape isn't enough.

Sometimes the threads in the rad. are so poorly finished, they just tear the PTFE to pieces as you start to wind the tail in.

If there's a lot of clearance in a thread, or the finish is poor, my preferred jointing is hemp and boss white.