Radiator thread/tail problem Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[officersmess]

In preparing to include a towel rail in my system I found that, whilst one of the radiator tails fitted perfectly the other was somewhat "slack", the thread being oversize (I suspect). No amount of standard PTFE tape would provide a leak free joint, and after much investigation I am to try a PTFE gas tape/Fernox LS-X combination. Is this a sensible solution? Would I smear the tail thread, then apply the gas tape, and also smear the radiator thread?
I had thought of having the joint brazed. Could that be done?

Your thoughts will be most welcome

officersmess

[htg engineer]

If you think the threads are wrong / damaged to either the towel rail or radiator valves, return them to where you bought them from for an exchange.

It is possible to get faulty goods bue to poor workmanship, damage in transit, or maybe the items you bought have been returned by another customer after damaging them.

3-4 layers of PTFE tape should be enough to make a watertight seal on any radiator valve.

[officersmess]

For fixing reasons I needed a radiator which was 1000mm wide and the only one I could find on the internet was in London, although it was probably manufactured in the Far East.
It is too much hassle for me to return it and I will therefore persevere with making it leakproof somehow.
I have no doubt that your solution is the correct one and who knows I may well have to cut my losses and buy another one.

officersmess

[The Heating Doctor]

If its not from the UK or made specific for the UK market the threads may not be BSP threads. Many other threads exist such as NPT, whitworth etc and even in tapperd threads rather than straight, This may be where the problem lies.

[officersmess]

I am satisfied that the threads are 1/2 BSP so that is not the problem

officersmess

[rosebery]

Just fitted a towel rail with exactly the same problem. No amount of PTFE would seal it even though the other sealed up fine with just two wraps.

The solution? Good old fashioned Bosswhite. Worked a treat.

Cheers

[officersmess]

Well done. I am probably too thick for that simple solution - I have just used Fernox LS-X. Will report again when I fit and open the valves tomorrow.

officersmess

[officersmess]

AHA!. Installed my towel rail today and WHOOPS! the fernox LS-X on the threads has solved the problem.

officersmess