F4 LEAK SEALER

[CTM]

I have installed new hot water cylinder "direct" used only with an immersion, not connected to any boiler, however, I have a slight weep from the fittings. No matter how much PTFE tape I use it still weeps.

Can you use F4 LEAK SEALER on a direct hot water cylinder.

 

[Whitespirit66]

No you can't. F4 is for adding to sealed systems like combis, via the radiators etc.

No additives should ever be added to a direct system like yours, as unlike a sealed system, whatever is added to your cylinder will be in the hot water that comes out of your taps. It is not designed to come into contact with skin, or possibly even be drunk.

Which of the connections on your cylinder is giving problems?

 

[CTM]

It is the supply and 2 off blank fittings that are leaking, the immersion and the outlet are OK.

The leak is only a slight weep and only when under the addiotiona pressure of the hot water tank head, the cylinder on its own doesn't leak if you isolate the supply at the bottom of the cylinder.

 

[seco services]

is it leaking on the mi side (thread) or the compression side of the fitting

 

[CTM]

It is leaking on the Mi threaded part, the compression fitting (olive) is Ok

 

[seco services]

did you wrap the ptfe the oppersite way to screwing it in ?
stops it coming undone when fitting.

 

[blondini]

Someone once recommended Fernox LS-X external leak sealer when I had a problem with a compression fitting that would not seal on a new cylinder. It worked a treat and now I always keep a tube handy.

http://www.fernox.com/?cccpage=ls_x&sub=4

 

[CTM]

I did wrap the PTFE tape the correct way, i.e. not causing it to unwrapp.

 

[seco services]

how many times did you go round

 

[CTM]

i have got some Fernox LS-X external leak I have had some sucess with it, however, I suppose I will just have to add more.

 

[CTM]

I can't remember how many times exactly, however it was a significan t no.

How may times would you recommend?

 

[seco services]

about 8