radiator extension tube

[paddy1]

I have a 47 " single panel radiator to be installed and my problem is that it was a 49" radiator there previously and the pipesfeeding the radiator are bedded in concrete.

I was planning to get a couple of radiator extension tubes and fitting them to save any hassle.

On looking at these parts I am unsure as to how to fit them.
I expected both ends to be threaded and one end connect to the radiator and the other the the valve but only one end is threaded and the other just has a rubber washer attached.

Can someone tell me how these are to be fitted.

Thank you.

 

[JPC]

fit the threaded side with the rubber into the rad. that way u have extended the female thread outwardly. if it was male thread on both side u'd have changed the set up !

 

[Roddders]

The end with external thread and and rubber washer goes into the radiator. I tend to put PTFE tape round this as an extra measure to ensure no leaks.

The other end internal thread fits onto the rad valve connection. However this will depend what valve you have got.

 

[kevplumb]

methinks you have

instead of

 

[paddy1]

It sounds like you guys are talking about an extension tube that has one male end thread and one female end.

The tube i have, on the end with the rubber seal the seal sits in a groove at the very end of the tube and has no threads that would allow it to be threaded into the rad.
The other end is fine and will connect to the nut on the rad valve.

does this make any sense.

 

[paddy1]

here is a picture of what i have


http://www.heatandplumb.com/acatalog/40mm_Radiator_Extension.html

 

[ChrisR]

The male threaded end screws into the rad (allen key inside)

The other end is designed to fit a valve of this type

You keep the nut from the valve but discard the part which went into the rad. So you'll have to take the old valve parts out of the old radiator to salvage the nut.

Thermostatic, and some other valves, have smaller unions in the middle so you'd need a different sort of extension.

 

[paddy1]

The existing valve rad valve on my pipe work has no nut and a male thread. The current rad valve has a male thread which goes into the radiator and the other end has a compression fitting and the nut attaches to the male thread on the valve.

If i remove the existing rad valve and screw in the extension tube the other end is to wide to fit a nut onto in order to attach it to the valve.

It seems that i have the wrong extension tube for the type of valve i have (vogue), but i cant imagine what type of valve this extension tube would fit.

here is what i have


http://www.inspiredheating.co.uk/acatalog/STELRAD_EXTENSION_ADAPTORS.html

 

[ChrisR]

Now you've shown us two compeletely different things which you say are pics of what you have!

 

[paddy1]

sorry Chris - i put in the wrong link.. doh.

The correct picture is the first one. Although the part I have is variable from 20mm to 40mm. The section that goes into the rad can be tightened from the other end using an allen key and then the outer sleeve slides out to extend the tube.

 

[ChrisR]

I can assure you the first type fits the valve I pictured. They only work with 3/4" rad unions (as pictured) though, which are about 32mm across the flats of the nut. If your nut would only be about 25mm that's a 1/2" and you'll need the other type of extension - or a new rad valve.

Rad valves with 3/4" unions are much easier to use where the pipes are rigidly fixed by tiles etc - the smaller type have the pipe going inside, which can be hard to get out when you want to remove the rad! You can't get the same type of sliding 1/2" size extensions.

 

[paddy1]

Youve hit the nail on the head.
so the fitting i have would have a 3/4 " nut go over the end which attaches to the rad valve, but in my case this would not work cause my nuts are 1/2" - don't laugh. so the bottom line is i have an extension suitable for a 3/4" rad valve.