Installing a towel rad on a sealed system Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[Gene12]

I want to replace my bathroom radiator with a towel radiator and will need to alter the pipework. I am reasonably ok with soldering fittings etc but is it ok for a novice to work on a sealed system (no tank in loft or h/w cylinder)? I have read of problems with boilers/c/h after work has been done and am a bit wary.
Assuming it's ok for me to do, is it better to drain and refill the system or use a pipe freezing kit. Obviously I will use push fit fittings if it is better to freeze the pipes.
Thank you

[marrtin]

It's probably easier to work on a pressurised system than it is a conventional type as they often empty and refill easier. Personally I have had mixed results with freezing kits as they often are at best unpredictable if not expensive. Easier just to drain what you need, fit the rad then flush and refill with inhibitor.

[chris_on_tour2002]

absolutely agree with marrtin, draining down and refilling is much easier on a sealed system, as you are refilling from the main via a filling loop you are far less likely to get airlocks and its generally much quicker. i've used pipe freezing kits on a few occasions but only where shutting off is more trouble than freezing (siezed cock for example). i once burst a pipe whilst freezing as the ice expands inside the pipe. beware! better to drain down and a good opportunity to add inhibitor. don't forget to turn off your boiler when draining down.