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٩(͡๏̯͡๏)۶&#
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Discussion Starter · #1 ·
I do believe me and houseplumber have had a few discussions about using brass compression fittings on cpvc. This is a great example why it shouldn't be done.

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THE PLUMBN8R
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What's up PT ?

noticed the sawzall to cut the grout.

not saying you didn't do an awesome job removing the tile and backing..

Have you tried this tool yet ? or the Fein ?

might make that job a little easier

loads of other stuff it will do...
like notching out wood thats in your way under a sink

or removing old grout seal from tub to tile seam
 

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AKA house plumber
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Thanks for mentioning me. :thumbup:
Ok now that that's out of the way I want to bring up a few points of interest. And by NO means am I defending cpvc.

1. I noticed the leak was on the hot side. What did they have their heater set at. Specs say no brass ferrels over 140.

2. It looks like they really over tighten the couplings on the cpvc. If you look at the videos again you'll notice the compression coupling on the cpvc is kicked at an angle. The ferrel was straight but over tighening can kick the coupling over on one side.

3. Dope. They put dope all over the cpvc instead of the threads on the coupling. Maybe the dope they used isn't compatible with cpvc. It looks like Blue majic, which is what I use. That is rated for cpvc. If you read on a cpvc x brass male KBI fitting it says to use tape only.
 

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looks like they over tightened the couplings to me.

i would have used MIP adapters instead of compression couplings if i did that tub.

i am surprised you didn't change out the other side while you were there, we know it is going to leak sometime down the line LOL

nice trick using the torch to soften the CPVC up so you could move it
 

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We have been using brass by cpvc adpt in these places instead of the cpvc ones also they make a copper to cpvc stub out that you can use also . Also wonder if heating the pipe to move it will damage it
 

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Looks like it was overtightened to me you could even see where one side of the ferrule is straight and the other is a little bent. Could of led to the issue,they say to use teflon on the ferrule. I also think that if teflon was used they wouldn't of had to kill it like they did.. Nice job on the repair by the way..

Got this from FlowGuard Gold CPVC tech manual...

Brass compression ferrules
CPVC pipe can be used with standard brass ferrules to make compression connections.
The O.D. of copper tube size (CTS) CPVC pipe is identical to that of copper. We
recommend that Teflon (PTFE) tape be applied over the ferrule to allow for the
dissimilar thermal expansion and contraction characteristics of the metal ferrule and
the plastic pipe that could possibly result in a drip leak over a period of time. Do not
over-torque the compression connection as over-torquing may result in a cracked
pipe. Non-metallic or nylon ferrules are not recommended.
 

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٩(͡๏̯͡๏)۶&#
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Discussion Starter · #10 ·
We have been using brass by cpvc adpt in these places instead of the cpvc ones also they make a copper to cpvc stub out that you can use also . Also wonder if heating the pipe to move it will damage it

the pipe is rated for 180 degrees
 

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Cool did not know the temp rating
We have had a lot of prob with the old cpvc getting brittle but this new gen stuff is doing alot better we use pex cutters to cut it and it cuts wright threw with out cracking I was wondering why you were cutting the pipe with a hand saw
 

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٩(͡๏̯͡๏)۶&#
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Discussion Starter · #12 ·
Thanks for mentioning me. :thumbup:
Ok now that that's out of the way I want to bring up a few points of interest. And by NO means am I defending cpvc.

1. I noticed the leak was on the hot side. What did they have their heater set at. Specs say no brass ferrels over 140.

2. It looks like they really over tighten the couplings on the cpvc. If you look at the videos again you'll notice the compression coupling on the cpvc is kicked at an angle. The ferrel was straight but over tighening can kick the coupling over on one side.

3. Dope. They put dope all over the cpvc instead of the threads on the coupling. Maybe the dope they used isn't compatible with cpvc. It looks like Blue majic, which is what I use. That is rated for cpvc. If you read on a cpvc x brass male KBI fitting it says to use tape only.
It was the cold water side, not the hot water side. heater was set at 125.

How does one determine when it is overtightened?

The dope is JC whitelam blue which is listed as compatible on flowguards spec sheet. I have seen these same failures with tape as well. Guess I'll have to make another video the next time I run across them.
 

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٩(͡๏̯͡๏)۶&#
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Discussion Starter · #13 ·
Cool did not know the temp rating
We have had a lot of prob with the old cpvc getting brittle but this new gen stuff is doing alot better we use pex cutters to cut it and it cuts wright threw with out cracking I was wondering why you were cutting the pipe with a hand saw
cutting with a pex cutter or ratchet cutter leaves a ridge on one side of the face of the cut. this ridge can wipe away the cement from the inside of the fitting causing leaks later on. If you use a bladed cutter you must then chamfer the pipe end before assembly. Read you manufacturers instructions.
 

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I've seen plumbers that just kill compression fittings where you really don't have to tighten them to that point. You need to be able to hand tighten any compression fitting for a few turns,and if you can't get a few turns on it then the pipe isn't lining up with your fitting correctly and that will cause the favoring of one side of the ferrule over the other. I was watching the second video and a good example of over-tightening the fitting is when the ferrule compresses so much that it bends the piping in on each side of the ferrule and causes a ripple inside. Also if you just look at the ferrule you can see it is compressed way to much.
 
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I've seen plumbers that just kill compression fittings where you really don't have to tighten then to that point. You need to be able to hand tighten any compression fitting for a few turns,and if you can't get a few turns on it then the pipe isn't lining up with your fitting correctly and that will cause the favoring of one side of the ferrule over the other. I was watching the second video and a good example of over-tightening the fitting is when the ferrule compresses so much that it bends the piping in on each side of the ferrule and causes a ripple inside. Also if you just look at the ferrule you can see it is compressed way to much.
:yes:. Also I meant to change what I said from hot side to cold side but got side tracked and logged out and forgot about it.
 
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