Bit of radiator plumbing advice needed

[a]

I have a towel rail which has a heating element, and which I intend at a later date to plumb in to a CH system.

There's a fair gap between the bottom of the rail and the floor. When (in the long run) I bring CH pipes up from under the floor, they won't reach the rail, a gap of two or three inches.

((This is because, as I don't want to take up the section of floor under the rail, I'll be manoeuvering pre-bent L-shaped pipes into place from the room next door, so the vertical sections cannot be much longer than the few inches under the floor.))

On one side of the rail this problem can be neatly overcome, as I've found a nice chrome "extension" that screws directly into the towel rail, and to which the tail can be connected, then the straight-line valve. Very neat and tidy.

On the other side is the heating element. There is a T-piece, so the valve needs to be L-shaped to connect to the rail and then down towards the floor.

I could put an extension piece between the T-piece and the rail, but this would bring the element head too close to the floor for my liking.

I could connect a nice chrome "elbow" to the T-piece, and then use a straight valve - but as "elbows" all appear to be female-female, as are valves, I'd need a little fragment of copper pipe between elbow and valve. Although this would prob. be okay, it would all be so much easier if I could find a female-male elbow, or a female-male valve, or just a particularly long L-shaped valve... but no luck...

Any suggestions as to the best solution, with the smallest number of joins? Thanks very much!

[Kevin]

hide the copper pipe

[Roger Mills]

Why not feed the bent piece of the pipe *down* from above - then the vertical piece can be the right length. You'll have to join it under the floor, of course - but if you use push-fit, that shouldn't be too difficult. The hole in the floor will need to be slightly bigger than the pipe diameter - but would anyway, using your method - to allow a bit of manoeuvring. You can get covers which fit round the pipe and cover up a slightly over-size hole.

[a]

Sorry to follow up my own question with another one.

Now have my towel rail in place (not plumbed into heating circuit yet) and have put some water in.

Unfortunately I'm getting some weeping from the bottom of the rail.

One side I have a tail extension and straight valve, followed by a sealing cap.

The other, I have the T-piece for the electric element, then from the horizontal arm of the T, an elbow, then short piece of copper tube, then another straight valve, followed by a sealing cap.

Two questions:

How tight can I safely tighten things into the base of the rail? I am scared of stripping the thread in the rail and I assume this would leave it quite useless (and it was fairly expensive).

I know I can tighten the side with the T-piece a bit more, but if I do then the horizontal part of it will face the wall, which is no good. What's the best way to have it fully tightened, but with the horizontal exit facing where I want it to face??

Thanks for any help!

"Roger Mills" wrote:

[DavidM]

Get a tube of Fernox LS-X from plumbers merchant or (maybe) a DIY shed. I often had problems with radiator tails and now always use this stuff. Apply a generous smear to the thread and screw in firmly but it doesn't need to be "grunt" tight. This way you can adjust the T piece to face the right way. The Fernox stuff is a bit like silicone sealant, only is designed for this sort of use and will set even under water and resist the pressure in the system. Try to not disturb the joint when you come to connect the pipes up. David

[Chewbacca]

Did you put plenty of PTFE tape onto the thread? If not make sure you remember to wrap in the right direction or it may leak. If you did it gets nice and snug - does not leak - but you can still manage another turn or so to allow you to point bits in the right direction.

[Roger Mills]

You don't mention what method of thread sealing you're using - so I fear you're not using any, and can thus expect leaks.

If you want this type of joint to be leak-proof whilst still giving scope to point it in the right direction, your best bet is to put some liquid PTFE on the threads before screwing it together. That will do the trick nicely, and is better - for this purpose - than the Fernox LS-X suggested by someone else.

[a]

Hi, thanks for the replies everyone... I had put a few turns of PTFE tape on the threads, but it seems this was not enough - I will give the Liquid PTFE a try next weekend and see how it goes!

[Chewbacca]

The tape is best as it will pack out the joint. Put plenty on a wrap following the thread so the tape is pulled tighter as you screw it in

[Roger Mills]

If you're using tape rather than liquid PTFE, the type intended for gas joints is best. It's thicker than the ordinary stuff and less likely to get shredded by the threads. But liquid is best if the final orientation matters.