Stop valve question

[600rob]

I'm need to replace an old kitchen sink tap that's leaking at the base... (Could repair but the chrome has seen better days)

The tap has solid copper tails and no isolator valves so I need to isolate the hot and cold before removing and replacing the taps.

There's two stop cocks under sink that I assumed were for hot and cold however when I shut what I thought was the cold supply, the cold tap still works.

When I shut the hot supply both taps stop working. The cold also branches off to a outside tap that also stops working
Can't see the pipe work behind the cupboard panels so i'm confused as to how both how and cold taps are being shut off....surely I'd have a separate
stop valve for each tap??

can anyone explain what kind of set up I've got going on here?

last thing I want is to remove the tap and flood the kitchen.

p.s the ch/hw is on combi boiler system

 

[oldbuffer]

1. Shut off the stopcock that shuts hot and cold off. If you shut off the cold to a combi boiler, it also shuts off the hot, because no water flows through the combi to be heated.
2. Open hot and cold taps.
3. If no water comes out, change the taps.
4. You may well find you have to cut the copper pipes to the old taps above the point where they get narrower in order to get the old tap out.
5. The new tap is likely to come with flexible hose connectors.
6. I'd suggest you connect the flexible connectors to a piece of pipe or an adaptor, and the other end of the pipe or adaptor into new full bore isolation valve, and then connect the other end of the isolation valves to the existing pipe. How you connect and what bits you need depends on the new tap.

 

[600rob]

Cheers for the info. I wasn't aware of point 1 as I've always had isolation valves before each tap tail or Flexi in the past.

Will stick some full bore valves in when I swap out the taps