Changing a radiator

[Gizmo_68]

I am in the process of changing the bathroom radaitor (10mm pipe) to a towel rail (15mm pipe),
with the CH system turned off is it possible to swap the current radiator valves for 10/15mm reducers (already connected to the towel radiator) without draining the system or freezing the pipes?
This is on a non pressurised boiler, so would it be possible to do this "live" without too much water loss, the floorboards are up at the moment so i can place a large bowl under the joints whilst changing them over,
or would this just be a bad idea?

 

[kevplumb]

dream on

 

[Gizmo_68]

Thought not but if you dont ask!

Are the pipe freezing kits any good?

 

[kevplumb]

get yoursen a 22mm speedfit stop end and a carrot
sure somebody will tell you why

 

[plumb_boy]

Drain it and use brass reducers!
I once "froze" my 10mm coated CH pipes to change a rad, using top notch rothenberger freezing kit down to about -15! I thought if it looks like an ice-pop then ALL IS SWEET.
Not so, with coated 10mm pipe it does an excellent job of insulating the pipe. Took the valves off and got totally covered in black rad water, not to good on a white polo shirt.

 

[Paul Barker]

What Kevplumb means is bung it. You can get a pair of purpose made rubber bungs or the wine cork tool with a lever, the carrot hadn't occured to me before, stop end is for the vent pipe.

Basically turn it into a sealed system by blocking the cold feed at bottom of f/e tank and blocking open vent. Draw some water from the drain off until it is held in suspension. Close drain off. Now you can break into the system one place at atime and there will be nothing more than a small puddle.

 

[breezer]

, the carrot hadn't occured to me before, stop end is for the vent pipe.

parsnip is better

 

[Gizmo_68]

Thanks guys , i knew there must be a simple way of doing it

 

[ChrisR]

Put the bungs in then let out whatever water comes from a drain cock - which you should have somewhere. You're trapping air in the vent pipe, and that'll always expand, letting some water out.
Close the drain cock - or leave it open!

 

[chrishutt]

Any chance of connecting the radiator valves into the towel rail? Then you wouldn't have to drain or anything.