Freeze and Brazing pipework?

[sg86]

Hi, is this possible to do? I'm trying to install a towel rad and need to move pipework, and i really want to avoid draining down the system at this time of year. Pipework is also microbore if that make any difference.

I guess there are some ways to join plastic pipe to this but i didn't think that was good to leave such joints inside walls, hence the question about brazing

many thanks!

 

[Paulus]

You would need to freeze a good distance from the soldering site, I would guess about a metre, but it can be done. I would have some push-fit stop ends at the ready just in case.

 

[SimonG]

Is your system open vented or sealed?

 

[cr0ft]

I've successfully soldered pipes within 10cm of an ice plug before, on a sealed system too. The sort of pressures an ice plug will hold back are well in excess of the pressures you find in any heating system. The secret to it is heat control, make sure you use an adjustable torch and it's not on full flame! Also, make sure you have a damp towel wrapped around the pipe near the heat plug. This stops the pipe there overheating and the plug melting.

With microbore you will have the fitting soldered before the rest of the pipe near it has even started to get warm. You can then control the heat transfer using the damp towel above!

And have a speedfit stop end/wet vac handy in case it does go.

 

[Riley]

Did my first frozen solder today. Was a bit twitchy bum but all good in the hood