Plumbing – Soldering soft copper to hard fitting

copper-tubinghvacplumbingsolderingwater

I'm trying to solder a soft copper coil to a regular fitting and its not working, (I did already a lot of soldering and never had a problem) is there any tips or tricks for soft copper? Do I have to work with it in a special way?
Thanks for any reply.

Best Answer

My guess is either the joint wasn't cleaned enough and/or not fluxed properly. I have had problems when my old tub of flux got dirt in it. When heating, the dirt burned and ruined the flux preventing a good solder joint. Check your flux and flux brush for dirt and replace or clean as needed. Then clean all of your joints thoroughly with one of those wire brush cleaners for copper tube or scotch bright.