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View Full Version : Connecting CPVC to Galvanized piping


jong66
Mar 10, 2008, 10:02 AM
I am trying to connect new cpvc to old Galv. Piping. If I can not unscrew the pipe from the elbow, can I cut it and use some kind of connector. Galv. Pipe is 1/2'. I am replacing old gal. waterpipes for 3/4 CPVC, except for the drop downs. Do I need a inspection for this job?

massplumber2008
Mar 10, 2008, 10:32 AM
Got you, Jong

Hey,sorry, but you need to unscrew the joints.. ok? No getting around it. If this was a waste or vent line then we could discuss other options, but this is water piping and the fact is that there is just too much pressure on these lines to do anything but transition by using threaded adapters.

If this was brass piping we also have alternative fittings... but not for galvanized pipe/fittings.

Just use a large enough wrench and an even larger wrench to hold against yourself (so do not disturb any other joints below/above joint you are working on). Old galvi. Water pipes should come apart pretty easy, then use plenty of teflon tape on pipe thread or cpvc male adapter transition fitting (I use 3-4 wraps on cpvc fittings turned clockwise... I use more on galvi. Threads) and you should be all set. AND do not use wrenches on cpvc fittings...just go two turns or so past hand tight..no more (use pliers ora strap wrench or similar). Let us know your thoughts.

And if you are a plumber then you need an inspection on this...as homeowner upgrading to cpvc...maybe not??

Just be sure that if you go anywhere near a water heater or any other appliance (such as boiler) that you come off the units with copper piping first (for about 18") then transition to cpvc, or leave at least 18" of the galvanized pipe on these units, then transition to cpvc.. ok?

And be sure you read the can(s) of cpvc cement/primer... some types use primer, some types don't. The biggest mistake people make with this stuff is using wrong cement and/or primer and overloading the cement into the joints (no need to overload.. just read instructions and keep it light... will be best in long run).

I don't know which kind of cpvc you are using, but here is a link to the flowguard cpvc site... lots of good information.

FlowGuard Gold Pipe & Fittings (http://www.flowguardgold.com/)

Hope this helped... Mark