Loctite 577 on radiator tails

[mitchino]

Fitted a towel radiator today, I ptfe taped the radiator tails, and after installation noticed the tails were leaking a tiny amount. So de-fitted, and smeared loctite 577 on the radiator tail threads. Reassembled, refitted and now wondering how long I have to wait until pressurising the system. It's only a 1 bar radiator circuit, do I have to wait 24 hours?

 

[SimonG]

What's it say on the instructions. I just use ptfe and paste, can pressurise immediately.

 

[mitchino]

there are graphs and charts showing curing time

https://docs.rs-online.com/27bc/0900766b8009020a.pdf

 

[ShaunCorbs]

Did you get the fitting tight or was it easy to put in

 

[mitchino]

The tails don’t fully tighten, if you screw them in too far they just end up inside the radiator. So after removing them and the ptfe I applied loctite and screwed them in again but they are not mega tight. Hoping the loctite creates a watertight seal

 

[ShaunCorbs]

24 hours

 

[oz-plumber]

If that's the case of rad tails screwing through the threads into the towel rail, I would question the company you bought it from.use

I personally don't like using paste sealants, and have had a few issues when joining dissimilar metals.
eg.. Brass and steel.

If I don't feel confident with a join, I wouldn't leave it

 

[mitchino]

all fine after 24 hours no leaks

 

[mitchino]

Spoke to soon, found new leak on one side, so stripped down and removed cured loctite 577, wound threads with a lot of ptfe, like 15 times round, and that seems to have finally done the trick. The radiator wouldn't get hot at first though, so now I'm enjoying a crash course in balancing, initial experiments have at least got heat to the thing.

 

[ShaunCorbs]

Yea ptfe normally requires anywhere from 15-22 wraps these days

 

[kristianB]

The tails don’t fully tighten, if you screw them in too far they just end up inside the radiator. So after removing them and the ptfe I applied loctite and screwed them in again but they are not mega tight. Hoping the loctite creates a watertight seal



Just fitting TRV to a 3 year old column radiator which required changing the tail from old style which requires you to tighten it from inside with large Allen key and you can tighten as per normal to a new tail has a square shaft allowing you to tighten from outside but as OP said the radiator has no end stop and the tail has no collar or end of thread so you can't tighten fully, so it leaks. About to try even more ptfe tape.

 

[Harvest Fields]

I only use loctite on rad tails now. Never have an issue. (Fingers crossed)

 

[kristianB]

Finally got it to seal - ptfe paste to fill the thread and then ptfe tape on top to kind of hold the paste in place. Loads of ptfe tape would have also worked I'm guessing but I hadn't much tape left.

It still feels like a bodge as I'm sure professional plumbers don't do it like this.

I'd emailed the place where I'd bought the radiator from saying how do I get a good seal and they just sent me a new radiator.