can i fit stopcocks in my central heating

[Mechanical Mike]

hi , i am refurbishing a room which currently has two radiators in it. i want to remove both, bin them, and carry out a load of work e.g. soundproof one wall knock all the plaster off the opposite wall fit insulation and then fitted wardrobes etc. At the end of the work i'll move the position of one of the rad so they are both located on the soundproofed wall, (i'll probably run the pipework in the sound proofing so they look neater).
FIRST QUESTION:
Can i cut the two 15mm feed and returns into the room and fit brass compression fitting stopcocks to them , then re do the pipework at my leisure and then when i'm ready refill these two rads from the main sealed system ? i.e. is it ok to have stopcocks permanantly in my central heating hidden under floorboards?
SECOND QUESTION:
Do I have to drain down the system below the level of these two rads ? or is there a way to cut this pipework wiithout flooding the living room below with ch water?

thanks in advance for any help.
(sealed system, weissman vitoden boiler in four pipe mode with hot water tank , ch in 2 zones (upstairs and down) plus with underfloor heating to 3 rooms)

 

[oldbuffer]

1. Don't fit stopcocks to CH, they can't take the heat for long periods. Same goes for isolation valves, except ones rated for central heating. If using isolation valves, fit full bore ones. You could use gate valves, but they tens to seize, and, in my experience, rarely shut off the flow fully after a year or two in place. Personally prefer to have no valves in the CH circuit except the motorised one and the TRV and lock shields on the radiators.
2. Better to either drain down below the level of the radiators, or freeze the pipes each side of the radiators. In either case fit compression stop ends and repeat drain down / freeze when refitting radiators.

 

[Mechanical Mike]

Hi , thanks for the response. I got the idea because the guy who did my bathroom fitted what looked like stopcocks or gate valves when he was adding two extra rads to the ch.
Are you saying there are CH rated isolation valves? Note they'd only be in isolation mode for 3 months then they would be full bore till the next idiot bought this house e.g. decades .

 

[oldbuffer]

Unless you get isolation valves rated for central heating temperatures (say continuous 85 degrees C, which is a bit over) there is a high probability they will leak, particularly once they have a flow through them.

Have a look at Pegler PB300T 25501 which are rate to 5 bar at 120 degrees. They are full bore.

 

[Mechanical Mike]

thanks, I hope the bathroom fitter used something appropriate! I've gone with the original advice and fitted compression stop ends. Thanks for the advice.