Portsmouth valve connection

[slioch]

I am sure this will have been asked a number of times before, so sorry if it has...

I needed to replace the portsmouth valve on the cold water tank that feeds the hot water tank recently. As the old one was prehistoric, and wouldn't budge, I cut it off, so also had to replace the brass 90 degree elbow as well.

However, I cannot seem to get a watertight seal between the 2 parts (both threaded - 1/2 inch). I made sure there was no vertical stress on the joint so that it would be in line and i've wrapped PTFE tape around the male part of the thread (6 or 7 times round), but there's always a slow drip. I've tried varying the number of times the tape is wound round the thread, removing the old stuff each time, but to no avail. Should it be wound round a lot more, or is there another method of creating a watertight seal?

Many thanks in advance.

 

[ChrisR]

Well the regs say you should be using a BS1212 opart 2,3 or 4 valve and not the old pompey.
That apart, yes they can be a pain.
Are you using a tap connector type fitting or an olive?
Both can work.
If you're using a red fibre washer with the former, put some leak sealer like Fernox LS-X around it and allow 15 mins to set.

 

[slioch]

Hi Chris,

I called it a portsmouth valve as that's what I identified it as. I am 99% certain the replacement I bought is a BS1212 part 2 (not at home to check it).

No olive involved. The brass elbow attaches to the copper pipe using a compression joint, and that is fine. The valve has a thread (male part), as does the brass elbow (female part), so I guess that means a "tap connector" type fitting.

All I have used is PTFE tape - no red fibre washer. Should I have bought this separately? Can the Fernox LS-X be used on it's own successfully?
Sorry, only had minimal plumbing experience, and not had problems like this before.

cheers

 

[kevplumb]

View media item 25330 View media item 25329
just a thought your not using a 1/2"" female iron by any chance (left pic)

 

[slioch]

Hmmm, possibly. Again, I am not at home, but I am certain it was brass, and I know that it does not have the hexagonal grip around the threaded end of the elbow.

What should I have got?

 

[kevplumb]

View media item 25333
bent tap connector and fibre washer

 

[slioch]

Ahh, so, my approach of standing in B&Q and employing a jigsaw type approach (this bit fits into this bit) wasn't correct then...

Not helped by the fact that the old one looks elbow looks exactly like the one I bought, so presumed it would be OK.

So, on that basis, I will be stopping by B&Q on the way home to buy something like this?:
http://www.diy.com/diy/jsp/bq/nav.j...refview=search&ts=1282138314222&isSearch=true

 

[kevplumb]

thats the beastie

make sure you get the fibre washer with it

 

[slioch]

Cheers - knew that something wasn't right, and wasn't convinced that more and more ptfe tape was the answer. Now I know. Thanks!

 

[kirkgas]

I am sure this will have been asked a number of times before, so sorry if it has...

I needed to replace the portsmouth valve on the cold water tank that feeds the hot water tank recently. As the old one was prehistoric, and wouldn't budge, I cut it off, so also had to replace the brass 90 degree elbow as well.

However, I cannot seem to get a watertight seal between the 2 parts (both threaded - 1/2 inch). I made sure there was no vertical stress on the joint so that it would be in line and i've wrapped PTFE tape around the male part of the thread (6 or 7 times round), but there's always a slow drip. I've tried varying the number of times the tape is wound round the thread, removing the old stuff each time, but to no avail. Should it be wound round a lot more, or is there another method of creating a watertight seal?

Many thanks in advance.

thats the prob change the number to 12-14

 

[slioch]

Wanted to say thanks - now have a watertight system! Bought the correct connector - part of the problem was that I replaced like-for-like. The existing connector was obviously wrong as well, but somehow the previous owners of the house got it watertight. Anyway, all sorted now, cheers.