Unvented system isolating procedure to fix leak

[Njcart]

Hi guys,

Wondering if anyone might be able to help... I have an unvented system and a leaking hot water tap for the upstairs bath. To sort this I am hoping I can just isolate the hot and cold water to the upstairs (to reach the bath taps I will need to disconnect both pipes) fix the leak and then turn the valves back and let the water flow again. Based on the isolation valves being the red and blue handled points at the top left of the image below (the pipes feed hot and cold water to upstairs), would anyone know if this is OK to do?

There is also a showers balance pipe (see second image) do I need to do anything with that?

Any help greatly appreciated and I can supply more phots/info if needed. If the answer is get a plumber I will do that just if its as easy as turning these valves then I should be able to fix the leak myself.

Thanks

 

[SpecialK]

Just try it and see if the water stops flowing? It will more than likely be the two valves top left.

 

[Njcart]

Thanks for the reply. I tried it and the water stopped practically immediately. This makes me wonder what happens to the water in the pipes between the valves and the taps. Is it just sitting in the pipes because there is no longer pressure to force it through? When I opened the valve again I heard the rush of water coming through the valve and the taps were running again.

When I take the pipe apart I assume this means some water will come out of the pipe. When I put it back together again there will then be air in the pipe up to the tap. When I turn on the valves again should I have the bath taps open to let this air out, or is it fine to keep the taps closed?

Thanks!

 

[SpecialK]

Yes it just sits in the pipes unless you can open a tap that is below the ones you are working on? Its fine to turn it back on with the taps open or shut. Sometimes its best to just open the valve a little in case you left something off where you were working. Less mess then!

 

[Njcart]

Thanks SpecialK.
Reassured!
I think I am working on the lowest tap so I will have a bucket at the ready!

 

[SpecialK]

Thanks SpecialK.
Reassured!
I think I am working on the lowest tap so I will have a bucket at the ready!

If its the lowest maybe open one above so it drains out...