As title really, have a couple of rads I need to repipe which are in the plasterers way.

I don’t want to drain the whole thing down to remove them and then have to do it again to repipe the rads.

Can I do this live by freezing the pipes or some other clever method? Was thinking of doing that and slapping some push fit or compression stops on to tie it over till it gets redone properly.

With speed fit you can do it so fast you could just put a few towels down. I’d do it with the heating off though, hot and pumped water would be no fun

I’d just drain the system, only takes 5 mins…

If you are just moving the radiator and the plasterer is OK with the pipes sticking up from the floor, just turned off both valves and remove the rad, draining it into a bowl. PTFE tape and caps on standby incase the valves are dribbly.

Obviously heating will be off! Hot pumped water would not be much fun no…
I could drain the system, but it’s not really a 5 minute job and then i’ve got to put inhibitors and things in, re bleed all the rads and faff only to do it again in a couple of weeks to do the job properly.

Not just as simple as pulling the rads off – the pipes for some reason run back and forth between 2 walls really stupidly so there’s no point the plasterer doing it until the pipes are gone.

you could freeze, cut and then cap with compression fittings.

I’d drain it and not bother with inhibitor for 2 weeks…

I’ve done it several times, using one of those twist pipe cutters and push on fittings. It’s quite exciting lol! If a sealed system I’d de-pressurize it a bit first mind or they’ll be a bang. I also recommend you use a push on isolating valve rather than an end cap if you want to connect back up at a later date, makes doing new plumbing simpler.

It is possible, but have everything to hand, including an assistant.

I needed to remove a live rad a while ago, under the instruction of a local college plumbing lecturer. He suggested that I could use the ‘ninja’ method. Sounded good to me, bring it on.

Step one, clean pipe at point to be cut. Remove paint etc, wire wool.
Step two, have cap to hand. Push fit will be best. I used a compression fitting isolating valve. If cutting high up on a vertical run, place a zip tie around the pipe to stop fittings falling out of reach.
Step three, with the isolating valve closed, tools to hand, assistant at the ready, cut the pipe. Immediately place the isolator/ cap onto the upper/ pumped/ pressurised end of the run.
There will be water. If the system is live it will be hot, possibly very hot indeed. This was an unexpected surprise to me, so I managed to drop all the fittings. Nothing for it but to shove my thumb over the squirting end. Ouch, that’s hot. Actually, it’s really, really hot. So I backed off a bit, only to be squirted with hot fluid. Push harder my plumbing friend said, so I did, putting in a slight twist as I did so.
Needless to say I had neglected to consider that the end might be sharp. It was, I sliced my thumb open, I pulled away, hot water squirted, I had to shove my thumb back.
Step four. Fit isolator whilst local expert rolls around on floor laughing his nuts off.
Step five, apply dressing to lacerated digit whilst dog cleans blood from wall and floor!

The lesson to be learned from this is not to listen to any suggestions about ninja shortcuts.

@Ambrose, is there a youtube link to this?

I replaced a rad. The rad I replaced was at the bottom of the system. I read on the internet that if I just released the pressure the water wouldn’t leak out because the top of my system is sealed. Like putting your finger over the top of a straw.

With trepidation, I tried it – and it worked. Had to let out the pressure first, but no spillage. Just undid the pipes.

I’d suggest you turn off all your radiators and then drain just the pipework. That way you can keep the bulk of the water and inhibitor trapped in the rads and you’ll only have to refill the pipework. Then you can safely cut and cap without worrying about ice plugs giving way. A few thick black plastic bags can be your best friends.

depressurise it then its easy. water will only trickle out and plenty of time to fit a compression fitting. Done it loads of times

Its a regular vented system so i dont think i can depressurise it as such? Im also cutting a vertical pipe 6ft below the flow/return so im assuming I’m going to get wet. Ah well, Like the idea of shutting off all rads, there is a drain point handily on the 2 rads im taking out so i think ill shut rads off, turn pump and heating off, drain from that pipe and see what happens. If it reduces to a trickle chop and ill be done!

Ah – if its a vented system then what I said will not work

Drain it down, and see it as an exuse to:

a) practice
b) use your intermediate fill is kind of a flush out – see how black it goes in a week
and c) won’t hurt to change the inhibitor anyway

Jeez Ambrose, I did say turn the heating off!

I have ninja fitted a t (well, 2, one on flow, one on return) to add a new rad to a system. Was easy, using Hep2O. I was uder the floor downstairs so if it all went wrong I was only draining the system out under the floor, no disaster. Oh and I shut every rad valve too, so then you are oly going to drain the pipe work which isn’t that much anyway. It really isn’t hard to do fast with pushfit fittings, but does take a bit of nerve.

Its a regular vented system so i dont think i can depressurise it as such?

You might have a tap to isolate the top tank. Mine has loads of taps that can isolate various bits.

Tank bung?

On my vented CH system, I usually close off all rad valves (making a note of the number of turns on each rad lockshield valve), fit a bung on the vent pipe in the loft, then just go for it with a few small containers and cloths to hand. You’ll get a bit of initial water loss, then it will subside significantly.

On completion reset all the rads valves back to their original setting to maintain the previous ‘balance’. One valve should always be fully open (or a TRV), the other is used to set the balance (which just makes sure the water flows are similar in each rad on the system). You’ll still need to chase a bit of air in the system afterwards but it’s much better than a full system drain down.