Sealing Parallel thread on Rad

[shaky1105]

H all, I've bought an Aeon Lunar Stainless Steel Radiator together with a pair of Ultraheat 90MFS Elbows (as the radiator feed pipes come from below) to fit in my Bathroom. However, I seem to have found a problem with attaching the elbows to the radiator in as such that the thread position makes it impossible to be able to tighten them correctly. Basically, when the O-Ring on the elbow seats against the radiator body, there is only about a sixteenth of a turn left before the elbow will be pointing down correctly on the left inlet and about three eighths of a turn (which may be enough to seal OK) on the right inlet. Attempting to turn the elbow another complete turn would be futile as it probably wouldn’t be possible and even if it were, it would more than likely crush & deform the O-Ring too much. I’ve tried starting the thread 180˚ out but it won't take.

I've been in touch with their technical department and one of their guys suggested using some Milliput on the threads to seal them but seeing as I've never used this stuff before (I believe it's a modelers epoxy putty ?) I was wondering if anything more plumbing-related, eg Loctite 55 or Flomasta thread sealer would be better ?

Any suggestions from you guys would be gratefully received.

TIA.

 

[oldbutnotdead]

Can you not use standard rad tails and put an elbow on them? Otherwise, yes loctite 55 or about 6 or 7 turns of PTFE will seal ok and make the O ring redundant.

 

[shaky1105]

Can you not use standard rad tails and put an elbow on them? Otherwise, yes loctite 55 or about 6 or 7 turns of PTFE will seal ok and make the O ring redundant.

Thanks for the suggestion buddy but the rad is only a max of 3" off the wall and the inlets into it face out to the rear, hence the need for the elbows to turn the feed downwards towards the feed pipes. I can't turn the elbows outwards either coz of lack of space.

I wouldn't want to trust PTFE as I've seen it get ragged up pretty well when fitting normal tapered threads but I've seen a few videos on Youtube and the like showing Loctite 55 but I wasn't sure if they were using it on parallel threads or not ?

It does look reasonably straight-forward to use, hopefully it's not just pro's making it look a lot easier than it actually is !

 

[fidom]

This stuff does irritate me as nobody seems to have noticed that we no longer plumb in radiators using iron pipe. Why can't they just come with short 22mm stub outlets that would go onto a compression or push fit plastic fitting?

 

[shaky1105]

This stuff does irritate me as nobody seems to have noticed that we no longer plumb in radiators using iron pipe. Why can't they just come with short 22mm stub outlets that would go onto a compression or push fit plastic fitting?

I am only a diy'er but I've thought the same as well, why have to mess about with tapered threads and PTFE etc etc when there MUSt be a better way ? I just presumed that, with me being a diy'er, there must be a good engineering reason for it that I don't know ?

 

[oldbuffer]

1. There are better ways, such as having a flat face to seat on and an "O" ring or flat rubber seal.
2. However, they are more expensive to produce than a rough and ready thread.
3. It is more difficult to produce a female tapered thread than a male tapered thread, which is why you normally find the female thread is plain, and only the male is tapered.

For the OP, check if Flomasta pipe seal will work with stainless steel (I think its fine, but probably not to be used with plastic). If it does then:
a. Clean male and female threads thoroughly.
b. Run a bead of pipe seal round the second, third and fourth threads of the male threaded part.
c. Screw together and leave in the correct orientation. Do this within a few seconds of application.
d. Leave for 1/2 hour and you've got a water tight seal and the right orientation.

 

[shaky1105]

Thanks for the reply @oldbuffer it's appreciated and sorry for the late reply and thanks from me but got caught up in some other stuff which took me away from the bathroom rad. I'll report back once I've had a go at it with how successful I was - cheers.

 

[Harry Bloomfield]

I've been in touch with their technical department and one of their guys suggested using some Milliput on the threads to seal them

The daftest idea I have heard this week so far. It is totally unsuitable, and impractical - there is no way you could possibly get it to stay put on the threads, long enough to even begin to screw the fitting in.

 

[shaky1105]

The daftest idea I have heard this week so far. It is totally unsuitable, and impractical - there is no way you could possibly get it to stay put on the threads, long enough to even begin to screw the fitting in.

I'm glad you said that Harry coz having never used it before (although I'd heard of it) and watching how it's applied etc on several youtube videos, I thought to myself it's time to either get the pros in or tell our lass we're having a different rad in the bathroom I certainly wouldn't have even contemplated trying it tbh. The guy from Pitacs seemed to believe in it though and said he'd tried it himself

Anyway, when I tested the tapered joint portion of the elbows, that I'd put together as normal with loads of PTFE, they hadn't sealed properly either (think I didn't nip them up enough really as I was a bit nervous of them getting damaged so prolly my fault) so I've dismantled them, cleaned them up and re-assembled them with a bit of the Flomasta thread seal so I'll have a test-bed to make sure that it's worked OK. I followed @oldbuffer's instructions and put some on the three threads then nipped them up reasonably tight with my Allen Key but will leave them until tomorrow before I test them.

Fingers crossed they'll be OK

Thanks again for the advice guys, much appreciated.

 

[shaky1105]

So, bit of an update. Some good, some bad . The thread seal worked perfectly so I'm well chuffed about that. Hopefully, it'll be just as successful on the rad elbows . The Ultraheat Elbows however, not so good put the joint together with a brass olive coz I'm using chrome pipe, half a turn after the olive had caught the pipe as I always do and my bloody spanner shot off the nut ! I thought maybe the nut had rounded-off but no, the thread on the fitting had gone oval and warped the nut with it . Thankfully, it's sealed OK but I can only assume that with the elbows being S/Steel, they ain't up to the job of withstanding the forces put on them by tightening the nut.

I certainly wouldn't recommend them now to anyone as I wouldn't have thought half a turn was over doing it.

Anyway, just got to hope that the elbows seal against the rad now with the thread seal but I'm gonna leave that until tomorrow seeing as I've had a decently successful day today.

 

[Justin Passing]

Milliput is stupid imo.
Rad bsp females are mostly tapered but they vary in diameter horribly, so ptfe tape only works with some if you use about 30 turns. Then it never goes properly tight on the wrench. Use the loctite 55 string instead. You can back it off, which isn't safe with tape. Don't use the thicker ptfe intended for gas. __ You should then get a full 360 of stopping position option.
For really awful rads you can put Fernox LS-X leak sealer or pipe thread liquid on as well. It works but you have to let it set.

FOr bad or slippery threads, roughen up the threads with a hacksaw to make the tape grip, if you're using a lot.

 

[Madrab]

Don't use the thicker ptfe intended for gas

Why not?

I use it all the time, have done for years - as that's what I carry with me - never had an issue. I think it looks terrible when a tail has had > 20 turns of water tape and it's all bunched up at the end.

 

[shaky1105]

Why not?
I use it all the time, have done for years - as that's what I carry with me.

I have been using the gas type tape as well. It's always worked for me in the past. These crappy elbows are the only tapered joint I've ever had a leak on and I'm not a pro.

 

[shaky1105]

Well, left the elbows attached to the rad for 24 hours before deciding to connect it into the rest of the system and I'm glad to say that there are no leaks at all and it's working fine .

Thanks again to all that offered their advice, it's really appreciated.

Just need to try and stop the general gurgling in the system now.......but that's another story