Failed gate valve: how to stop hot water supply in flat?

[ianm]

Hi,
I need to replace the back nut on my hot bath tap. However, the gate valve on the cold water supply to the HWC seems to have failed and still allows a flow through the hot tap even when closed. I live in a flat, presumably with a shared cold water tank somewhere in the loft to which I don't have access. Is there any way I can stop the hot water supply to do this repair? Or failing that, is it a terrible idea to disconnect the pipe to the hot tap with the water still flowing slightly, quickly replace the back nut and reconnect the pipe?

Thanks,
Ian

 

[Dotty]

Gas. The trusted advisors are that for a reason. Please don't accuse them of giving daft responses or scare mongering on a thread such as this.

The OP would be best to get a plumber in as advised. And snatching in this scenario is most certainly not to be advised.

 

[Killy Bing]

Use a local plumber, he can decide with the best route to take and in the event there is a leak it would be down to him and his insurances.

Hey gas, you might be local!

 

[ianm]

Hi,
OP here, thanks for all the replies. They were all very helpful and I can understand the different points of view. My feeling is that as a DIYer I most probably could manage to do the job, but just to guard against the small chance of something going horribly wrong I should this time get in a plumber and also get the faulty gate valve replaced, so that next time I CAN do it myself.

Cheers,
Ian

P.S. Some kind of hinged or two-piece back nut would indeed solve the problem, but my googling failed to find any such thing.

 

[Dannypipe]

The guys are talking about a top hat washer, a split type like this:SplitKlick - Home

But that's only useful if the backnut is still useable and not cracked.

 

[Dannypipe]

If you do want to buy some top hat washers, you can order them online here:
Split Klick Top Hat Washers Pack of 10 | NoLinkingToThis

 

[Bunker]

Ian, as you are obviously interested in achieving this (hats off for that), why not speak to whoever manages the freehold etc and find out how to access the tank - they really should facilitate that and you'll probably find your plumber might want to anyway.

 

[solutions]

Would this not be a perfect situation to use one of those new clamp on replacement lever valves? Would allow you to issolate the cold supply to the hot tank that the faulty gate cant. Golden rule of plumbing "isolation" fulfilled and work can comence with gusto.

 

[Mike Jackson]

It would if they were available in 22mm. As far as I'm aware they only make them in 15mm at present.

 

[Dotty]

It would if they were available in 22mm. As far as I'm aware they only make them in 15mm at present.

Beat me to it Mike.

 

[Leo21]

It would if they were available in 22mm. As far as I'm aware they only make them in 15mm at present.

Couldnt you snatch a 15 x 22 comp reducer in and then fit one?

 

[Phil]

Couldnt you snatch a 15 x 22 comp reducer in and then fit one?

A diy snatch to end up with a 15mm clyinder cold feed Leo?

 

[Gas]

A diy snatch to end up with a 15mm clyinder cold feed Leo?

Yeah, it be alright, he is gassafe, look under his user name.

 

[Gas]

Two piece back nuts, designed just for this application.

It is probably a no, but have you got a link for this?

 

[Leo21]

A diy snatch to end up with a 15mm clyinder cold feed Leo?

If I was being serious and not joking. Yes!
And just to clarify I was joking. If you were going to snatch it, you'd snatch a new valve in! 22mm of course.

 

[Howsie]

Sorry, I am not going to treat the op like an idiot, he knows the gate valve is passing from cwsc, thus in the past month alone, knows more than a fair few plumbers arms members

You think?

 

[Mickyplumb]

Try a Nerrad Jet Swet. Go to the youtbe video, the guy sticks it through an open gate vale.

 

[solutions]

It would if they were available in 22mm. As far as I'm aware they only make them in 15mm at present.

That I did not know. I guess 22 is just too hard to crush down away from the valve insert when its been cut. either that or they just haven't released it yet. Seems strange to have a potentialy game changing product but only offer it in a 15mm size.

 

[Gas]

Try a Nerrad Jet Swet. Go to the youtbe video, the guy sticks it through an open gate vale.

Video cuts and resumes right at the point that we actually wanted to see, what a terrible promotional video.