FLARE Fittings on soft copper for water lines?
#1
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Anyone have any longterm experience using flare fittings on soft copper pipe for domestic water? Do they hold up over time? Leaks / catastrophic failures? Just looking for feedback since they don't seem too commonly used for water.
I'm looking to connect some new type L 1/2" soft copper lines in a tiny attic space. Objective: Don't burn the house down, or flood it. Water pressure is 75psi from main.
Options are: 1. Solder -space is very tight, inches from wood and insulation. 2. Compression ferrule fittings -never had good luck with these, also possibly not for use with soft copper? 3. Sharkbite -not for use with soft copper. 4. "ProPress fittings" -manufacturer says soft copper is ok, but the tool is $2k new and $200 to rent. 4. Flare fittings -seems better than standard compression fittings but I have no experience with them.
Thanks
I'm looking to connect some new type L 1/2" soft copper lines in a tiny attic space. Objective: Don't burn the house down, or flood it. Water pressure is 75psi from main.
Options are: 1. Solder -space is very tight, inches from wood and insulation. 2. Compression ferrule fittings -never had good luck with these, also possibly not for use with soft copper? 3. Sharkbite -not for use with soft copper. 4. "ProPress fittings" -manufacturer says soft copper is ok, but the tool is $2k new and $200 to rent. 4. Flare fittings -seems better than standard compression fittings but I have no experience with them.
Thanks
#2
I would use compression... But you can flare if you want. As a plumber its not something I do with water lines... It was old days we flared the copper 1" underground soft copper water mains/ service..
Why dont you just run pex...Thats what I would do...
Why dont you just run pex...Thats what I would do...
#3
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It's probably been 30 yrs since I've used flared fittings on copper water lines but I don't recall ever having any issues when it was done correctly. If it didn't leak in the first 5 minutes it wasn't likely to leak 5 yrs later.
#5
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Absolutely nothing wrong with using flared fittings. Before the advent of the pre-made flexible hoses faucets were connected to the stop valves with soft temper copper tubing and "slip" washers with nuts. There were no "coned" flexible tubes and the straight tubing ends could, and would on occasion, pop out of the nuts and washers making a huge mess. Going with flared fittings cured that problem once and for all.
Further, with the quality, or more correctly, LACK of quality in the commonly available compression fittings I simply refuse to use them.
I have a flameless means of soldering copper piping but it has a fairly steep price, north of $100.
Further, with the quality, or more correctly, LACK of quality in the commonly available compression fittings I simply refuse to use them.
I have a flameless means of soldering copper piping but it has a fairly steep price, north of $100.
#6
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Kiss
KISS is an acronym for "Keep it simple, stupid" as a design principle noted by the U.S. Navy in 1960. The KISS principle states that most systems work best if they are kept simple rather than made complicated; therefore simplicity should be a key goal in design and unnecessary complexity should be avoided.
Now that I've learned to solder I like doing that but I also have flared fittings and they last forever.
Now that I've learned to solder I like doing that but I also have flared fittings and they last forever.

#7
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Thanks for the responses. Got a little of everything but I was glad to hear that there's nothing wrong with flares. My local Home Depot didn't have lead free flare fittings so I first tried compression fittings, and all 4 connections leaked. Either the pipe was slightly deformed or I over tightened them, or more likely the fittings were poorly made. They seemed to hold until I jostled the pipe a bit and saw them weeping. After tightening further I got a nice little stream going. My opinion now is that compression fittings are terrible for soft copper larger than 1/4".
Second shot was with flare fittings. Drove all over town to find some Watt's Lead Free 5/8" comp, x 1/2" male. Flaring copper for the first time was surprisingly easy, the tool was $26 from Home Depot. Did one practice run and then made the 4 connections in the tight attic space. No leaks at all, I even jerked the pipes around a bit as a test. I'm not sure why flare fittings are not more commonly used, just looking at them they seem like a much more mechanically sound fitting. Anyhow, it's done and I feel confident they're going to hold up well.
Cheers!
Second shot was with flare fittings. Drove all over town to find some Watt's Lead Free 5/8" comp, x 1/2" male. Flaring copper for the first time was surprisingly easy, the tool was $26 from Home Depot. Did one practice run and then made the 4 connections in the tight attic space. No leaks at all, I even jerked the pipes around a bit as a test. I'm not sure why flare fittings are not more commonly used, just looking at them they seem like a much more mechanically sound fitting. Anyhow, it's done and I feel confident they're going to hold up well.
Cheers!
#8
They seemed to hold until I jostled the pipe a bit and saw them weeping. After tightening further I got a nice little stream going. My opinion now is that compression fittings are terrible for soft copper larger than 1/4".
#10
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I've never used a compression fitting but to me it's pretty hard to screw up a simple flare fitting as long as you remember to slip the nut part on before you do the flare. 
Good job you got 'er done..

Good job you got 'er done..
