Leaking compression joint at calorifier

[John_Clarke]

The compression fitting on the copper pipe coming out of my calorifier has been leaking for several years. I have tried tightening it but it still leaks. What should I try next?

Would some Sikaflex around the olive ring be worth trying?

 

[richardh10]

Some PTFE tape around the olive would be better

 

[KellysEye]

>Some PTFE tape around the olive would be better

Agree.It's either leaking from vibration or being over tightened. If the PTFE tape doesn't work then you will need to replace the olive, you can do that if you have slack in the copper pipe. If you do have slack use a pipe cutter to cut just behind the olive and be careful not to over tighten the replacement olive. If you don't have slack it's a new pipe and olives.

 

[ctva]

I had to use quite a bit of PTFE tape to seal the thread joints when I installed a Nautiquick calorifier a few years ago. If it does not stop the leak first time, don't keep tightening too much, take it off and put on a bit more. I split one fillting tightening it up too much!!

Also, wrap the tape in the same direction as the thread as it stays in place better.

 

[John_Clarke]

Thank you - 3 in favour of PTFE. I will try PTFE tape next. I read somewhere that PTFE is for use on tapered threads to reduce friction so they can be done up tighter but it sounds like it can be used to seal an olive joint too.

 

[michael_w]

As you've probably overtightened the fitting it'll leak for evermore. Cut it off and try again, just a bit more than hand tight will do the trick.

 

[RobinBirch]

A good clean up, some Hylomar Universal Blue around the olive and the threads then tighten up would be my recommendation.

 

[Plevier]

A good clean up, some Hylomar Universal Blue around the olive and the threads then tighten up would be my recommendation.

Or Red Hermetite or Calortite (which I always suspect is Red Hermetite anyway) I use whichever is handy. Prefer that to PTFE tape.

 

[VicS]

+ another vote for a jointing compound

Something heavier than Hylomar I think, excellent though it is

"Boss White" perhaps

 

[Sandyman]

Take it from an old plumber Hemp & Boss White will do the trick lol but in the long term best to replace with new pipe & olive
.............and a dab of Boss White on the thread.

 

[PCUK]

You can bodge it with jollop or do it properly with a new olive and pipe as already said.

 

[John_Clarke]

I am reluctant to bodge it but it may be worth trying hemp and Boss White first to see if it does the job. I will have a look to see what is involved in replacing the pipe - I think the joint at the calorifier tank is covered in green foam insulation.

 

[superheat6k]

Loctite grade 577 is the best thread sealant I have ever used, simply brilliant. I use it on all plumbing and threaded fittings, and once applied the fittings simply do not leak.

 

[John_Clarke]

Loctite 577 is expensive but if it stops the leak it would be worth it to save a lot of work. I have been impressed with other Loctite products so I have ordered some to give it a try.

 

[ostell]

It's not the thread that stops leak in compression joint so PTFE round the thread will not help much. Take the fitting apart and clean all the jointing surfaces with wire wool, including the surfaces inside the brass fitting. Smear all mating surfaces with Boss White and assemble but not overtight. If that doesn't work then it's going to have to be replaced.

It's probably failed because it has been overtightened.