Impossible to turn off water at mains- what can be done?

[rsatterley]

While waiting to speak to our plumber, I thought I'd post my problem here to see what people think.

Essentially, there is a falling main which brings cold water from a
roof tank into the bathroom taps. This tank contains gallons of water and serves multiple properties. Because of this, it can not
realistically be turned off (i.e. it would take days to empty it and
would affect other properties). We have done a 'rush job' and
affixed a ball-fix valve on, to be able to stop water coming to the
taps, but we are not 100% confident that this is sufficient. The
offending pipe has an old stop gate valve, which is broken. This pipeis an old-fashioned one, measuring approximately 28 mm in diameter. The property is a maisonette, part of an estate built in 1965. So there are maisonettes on both sides, and small flats above us.

Is there a way to fix the stop gate valve without turning the mains water off??

 

[GuessMan]

Hire an electric pipe freezer and fit a new 28mm stopcock. Bear in mind it is VERY hard to freeze running water, a gas one will cost a fortune and may not work!

 

[picasso]

If the tank is accessible you could try bunging the outlet to the broken valve from inside the tank, good luck whatever with your problem, always a bit nerve wracking dealing with this sort of stuff

 

[gasbanni]

You may find if you inspect the tank it has a large stop valve on the outlet,

As it only serves bathrooms and wouldnt cut the water off totally to other properties I would have no hesitation in letting everyone know the waters going to be off for "Essential maintenance work".

Ps whilst this is going on look in the tank it might need cleaning out, you might want to use fresh water to clean your teeth !

 

[HERTS P&D]

Phone around for a plumber who has a Freeze Master who can freeze the pipework.

Andy

 

[rsatterley]

Thanks everyone. The plumber is coming by today. If he's unable to freeze it I'll go back to the porters and see if we can turn off the water at the source of the tank. And **** off all of my neighbours for the next couple of days...

 

[dazza87]

snatch it live live on the edge.
Pipe slice ,bag to catch water,new gate valve.
piece of cake.

 

[rsatterley]

We'll give that a go if freezing doesn't work!

 

[HERTS P&D]

snatch it live live on the edge.
Pipe slice ,bag to catch water,new gate valve.
piece of cake.

What on 28mm pipe work???

Andy

 

[diyAlex]

This pipeis an old-fashioned one, measuring approximately 28 mm in diameter

If it really is "approx 28mm" OD then are you actually dealing with 1" imperial (which is measured on the internal diameter) ?

 

[Dan Robinson]

So 28mm will fit, but with a little "persuasion".

Wouldn't catch me doing it live though

 

[picasso]

Probably a 100 gallon tank and you cant turn the mains off to it, what could possibly go wrong snatching it.

 

[Valve]

Maybe you could try the Aladdin Easyfit Isolator - I've just asked in another post if anyones used this. I'm trying to isolate a leaking pipe that won't freeze. Not sure if they do it in this size.

 

[Valve]

errr - that wasn't spam, that was my post to see if anyone has tried this product - wondered why it disappeared!

 

[Charnwood]

Maybe you could try the Aladdin Easyfit Isolator

Or maybe not.

DO NOT fit to 15mm steel or any pipe that is not 15mm.
This product is only for 15mm copper pipe (Hard or Half Hard, 0.7mm or 1mm walls) or plastic pipe (PEX and Polybutylene).