Leaking top connection of heating coil on hot water cylinder

[flinty]

I have a pre insulated hot water cylinder with a central heating coin going through it to heat the water.
The connection at the top has started to leak.
There is a nut that sits directly against the cylinder and seems to hold the coil in place. This looks like where the leak is coming from.
Can the nut be undone and then PTFE wrapped around the threads and the nut replaced (obviously draining down the cylinder first).
Or is ther another solution.

 

[gas4you]

I dont think ptfe around the threads will help. You will need some form of seal or washer aginst the cylinder. The thread is just the mechanical device to hold it in place, but no doubt ptfe would be a useful extra.

 

[flinty]

I would hope there is something behind the nut already and it is that thats failed.

 

[Agile]

You need to see the tightness of the nut.

They always seem very tight when supplied and there is some type of sealing washer on the INSIDE of the cylinder.

Whatever you do DONT allow the threaded part to turn as that will twist and flatten the heating coil inside.

If it feels loose then I would drain the cylinder and run the nut back about 15 mm and dry and put silicone grease on the threads and flange to lubricate them so that they exert more force when its retightened.

That might work!

Tony

 

[flinty]

This isn't a new cylinder.. it has been in for 10 years (since the house was built), but looking at the nut there is a fair amount of scale around it.

 

[wilhelm]

undo nut.

put in insurance claim for resultant flood.

buy villa in majorca.


or get new cylinder.

 

[moliver34]

Quicker to replace it then

 

[namsag]

As gas4you says replace the washer between the nut and the cylinder, easiest way to undo nut is drain cylinder and loosen nut if you can get into it while all pipewok is still attached to it, this will help to support coil. Hardest thing will be finding the corect size washer or get a sheet of gasket material and make one.

New cylinder minimum £160, washer pennies so know what route i would try first.. We used to use pump washers as we had about half a dozen types and one used to fit, but the ones that come with pump valves now are not any use (too thin)

 

[flinty]

Problem fixed... and only 10p for the washer (I just trimmed it to fit)

Thanks for the help.