radiator valves All aspects of plumbing questions and answers, help, tips and information

[bezthedog]

Hi i am wanting to replace a couple of radiator valves the trouble is i dont want to drain the system if possible. i have heard you can buy a spray that freezes the pipe for about 20 mins while you work on the radiator is this true

Thanks :oops

[Steve the gas]

Sort of ............. but I wouldn't bother.
If your'e not confident get someone in by recomendation.

[screech]

Search Screwfix for "Pipe Freezing Kit"

never used the stuff myself, but also never drain a system. i also bung it and create a vacuum instead.

[htg engineer]

So you freeze the water - fit the new valve, what happens if one of the joints is leaking ?

You cannot freeze moving water, draining takes time - carpets/flooring ruined ????

htg

[plumbbob]

I only use freeze kits if I think a) if they will work, b) alternatives are likely to be awkward.

You cannot freeze close to the working area and won't work reliably in vertical pipes.

Freezing is difficult, unreliable, and expensive. One £6 can freezes one 15mm pipe for 20 mins (you hope) so two rads = 4 pipes = £24 and there is no guarantee it will work.

If you have a pressurised system simply dropping the pressure and emptying the rad may be sufficient to stop any water escaping so you can change the valve.

Best way to a heart attack is to freeze a pipe then get stuck trying to do the new connection.

[chris_on_tour2002]

you can also be overzealous with the freezing agent, overexpand the water and burst the pipe - as happened to me recently when changing a stuck gate valve on a CWSC mains feed. had to use another freezing kit to repair the damaged pipe!

not for the uninitiated.

[plumbbob]

Not for the faint hearted either.