Shutting off water supply to toilet

[Egmond]

Hello I'm a new poster (with, I think, an entry level question).

I'm trying to shut off the water going into the upstairs toilet cistern so that I can replace a faulty inlet valve in it. This is proving difficult.

On my loft tank there are 2 pipes emerging at the bottom, both with taps. One is a simple T-shaped tap head and the other is one of the red round type tap handles. They were stiff but I've managed to close both. However, the toilet cistern is still filling up as normal after 3 flushes - not even any apparent slowdown in the inflow. The sink and bath taps are also both still working. The only difference seems to be that the sink tap (a mono tap) isn't working when pushed to the 'cold' position, the mono bath filler tap seems unaffected. Have I missed something?

[EDIT (sorry, actually there are 3 pipes coming out of the bottom of the loft tank but I think the third (with no tap at the tank) is the cold inlet for the power shower pump. ] There are a couple of other taps in the bathroom cupboard where the hot water cistern is. These are on pipes going (I think) into the shower pump. These are Cold Inlet and Hot Inlet into the shower pump. None of these seem movable and I assume they're irrelevant.

Thanks in advance for any advice.

 

[HERTS P&D]

Is there an isolation valve under the toilet?

If not then turn off the mains and drain down then fit a new isolation valve and go from there.

Andy

 

[matt1976]

Are you sure they are supplied from the tank and not the mains water supply?

 

[Egmond]

Is there an isolation valve under the toilet?

If not then turn off the mains and drain down then fit a new isolation valve and go from there.

Andy

Thanks. There isn't but thanks anyway.

 

[Egmond]

Are you sure they are supplied from the tank and not the mains water supply?

No, I assumed they had to be supplied from the tank. (I'm a proper noob at this). I'm not sure where the mains itself is turned off but now I know it's not necessarily the tank I will investigate but it will have to be tomorrow.

Thanks for this.

 

[HERTS P&D]

You do have a stopcock.........................some where!

Andy

 

[RogerMellie]

Finding that stopcock would be wise, if you do have an unexpected plumbing emergency ( nail through pipe for example !) being able to get to the stopcock and isolate the water supply is going to save you a lot of grief.
Suggestions of where the stopcock is hiding, near your water meter if you have one, in the cellar, under the kitchen sink (sometimes hidden behind a panel by kitchen fitters) or maybe in a downstairs toilet.

 

[HERTS P&D]

Or front garden/pavement.

Andy

 

[Egmond]

This is now sorted, courtesy of the advice above, using the tap under the ktichen units, I knew there was one there but thought it would only affect cold water downstairs (+ appliances etc) so now I know for the future.

Thanks again to all who posted.