Third hot water compression fitting's center keeps cracking

[not_plumber]

There's a 30 foot run of 1/2" copper hot water pipe that was cut where a compression fitting was installed. I replaced this hot water fitting 3 times with a new one of the same type that was on there that had gotten old and rubber seals dryrotted away which means it was leaking badly. The new ones keep cracking in the center. One lasted 3 days. Another lasted 6 hours. Then, the previous one lasted over a week. This is the exact product actually https://www.lowes.com/pd/AMERICAN-VALVE-1-1-2-PVC-Compression-Coupling/3132327

I was asked why don't I just use Sharkbite brass 1/2 push to connect (https://www.lowes.com/pd/SharkBite-...ect-dia-Slip-Coupling-Push-Fitting/1000182689). I knew it wouldnt crack in the center and thought it would be great. Turns out it won't even slip onto either pipe. It butts up to the pipes because they're the same diameter. I sanded "deburred" the pipes ends, washed off, then used vaseline on the pipe and the sharkbite entry and neither pipe would enter. I've read somewhere this could be from the pipes have frozen and expanding in the past but all I know is those pipes weren't going in. Link to pic: https://imgur.com/gLWNWPE

If I try to solder next, what materials will I need to solder besides a torch, solder, flux, and like a 5/8 copper pipe to fit over the ends of the pipes I'm joining soldering?

Is there a way I can join these two copper pipes using pex connectors and pex even though its only like 3-4 inches gap from pipe end to end? What would a plumber do to join these pipes at this point? Is there a way I could be installing the compression fittings wrong if they are cracking in the center? I do not think so since it is too simple and tighten them just enough that they wont leak and will hold onto the pipes.

So I'm not a plumber and its shitty to squeeze under neath house but considering replacing the whole 30 foot run with pex. I do not see a plumber taking this job because there is no room to work or get to pipes unless you dig beforehand and are skinny. That copper pipe is old anyways. My only concern though is the two end connections. One of the ends I have to dig to even get underneath that area of the house to see how it's joined. The other end is shown in the picture below which goes to the bathtub. Do I disconnect that copper pipe's end just by turning that upper brass nut CCW with an the open end of a wrench and gripping the brass center with channel lock pliers? See my concern is that I will not find locally at Lowes a connector for connecting PEX tubing to the faucet assembly as the copper pipe has what looks like a fitting screwed onto it and onto the brass faucet assembly. What connector connects pex tubing to this bathtub assembly? Link to pic: https://imgur.com/DmP0ttl

 

[Reach4]

This is the exact product actually https://www.lowes.com/pd/AMERICAN-VALVE-1-1-2-PVC-Compression-Coupling/3132327

That one is for 1.5 PVC and not for hot water.

Turns out it won't even slip onto either pipe. It butts up to the pipes because they're the same diameter. I sanded "deburred" the pipes ends, washed off, then used vaseline on the pipe and the sharkbite entry an

Don't use vaseline on rubber. Instead get some silicone grease. The Sharkbites are supposed to come pre-greased.

If you really have 1/2 inch copper (5/8 OD) you would want one SharkBite U3008LF repair coupling, a regular U008LF coupling, and a short piece of pipe. The repair coupling can only bridge 2 inches if I read correctly. The thing I wonder about is whether the pipe is really normal -size 1/2 inch copper. If it is, then I presume you did not debur the ends sufficiently. http://www.sharkbite.com/product/slip-couplings-slip-end-only-suitable-for-copper-and-cpvc/

You need a water pressure gauge. See what pressure you have that helped crack those units. They can be pretty cheap. Also, I suspect you are on city water, and that you may not have a working thermal expansion tank. Read up on those and the need for them.

 

[Sponsor]

 

[Master Plumber Mark]

you are installing JUNK... what do you expect it to do???



Just go get a 1/2 shark bite coupling and try that... and if that does not work
which is should then run a new PEX line..

 

[not_plumber]

The pipe was swollen. I cut it out using a cutter tool. Put a sharkbite 1/2 pushon that is connecting copper pipe at one end where it was not swollen to 1/2 pex tube that is 20 feet to where I made the next copper pipe cut where it was not swollen. Except that this cut did not make as clean of a cut as the one previously done on the copper pipe. Deburred the end as previously done but the second sharkbite would not accept the copper pipe. Reason being the pipe is not as perfect as the cutting tool did some bending not just cutting. This is underground and cannot make another cut on the copper pipe to chance a better cut as I barely was able to cut it in this location too close to concrete and a metal drain pipe where I cant turn the cutting tool a full rotation without hitting either of those.

Since I couldn't fit the second sharkbite onto the other copper pipe, I needed a way to connect copper to pex. So I am using this same plastic compression coupling (https://www.lowes.com/pd/AMERICAN-VALVE-1-2-in-dia-Coupling-CPVC-Fittings/1000364871) to make the final connection instead of the sharkbite that wouldnt go over the copper. Not without trouble though. I inserted the PEX and copper equally deep into this coupling and hand tighten. When I turn water on else after using the water for some time (likely when I close a faucet valve off) it shoots out the PEX tubing. Then it floods the whole area. This has happened five times where I have swapped cap ends and tightened down on the PEX side of the coupling. My water pressure is not high. It just keeps shooting out the PEX. Is this coupling not meant to join PEX and copper? It is holding right now for a few hours but I dont know how long that it will last from experience. Copper side never has shot away from. Water is coming from the copper to the PEX though.

I've thought of finding a reshaping tool for the copper end so that maybe I can retry the sharkbite.

What are ways for connecting this 1/2 copper pipe to 1/2 pex? Can I use a nut and ferrule? I've used nut and ferrule for smaller diameter tubing and copper piping and never leaks. What would a plumber do to connect a slightly deformed copper end to perfectly straight cut PEX?

 

[Reach4]

I've thought of finding a reshaping tool for the copper end so that maybe I can retry the Sharkbite.

What are ways for connecting this 1/2 copper pipe to 1/2 PEX? Can I use a nut and ferrule? I've used nut and ferrule for smaller diameter tubing and copper piping and never leaks.

Sounds like your pipe cutter was dull or it was made for steel pipe.

Reshaping can work. Maybe use an angle grinder to take a little off of the end. Or just use a file to take the burr off.

If you can get the nut and ferrule over the pipe, you can definitely use a compression fitting if you find the one you want. You have to use a fair amount of torque. When you put a compression fitting on copper, no insert is used. When you put a compression fitting on PEX, you need an insert.

Are you sure you can't solder it?

 

[Master Plumber Mark]

if the pipe is swollen due to freezeing you are kinda screwed....

you will have to find an old fashoned tool called a swedger which you pound into the
copper pipe and enlarge the copper to the OD diameter of a fitting... Then you clean out the
inside of the copper with a brush and solder a peice of copper into the swedged pipe....

it if swelled up due to freezing that is the only way its gonna happen

 

[Terry]

What people will do on a hot day to cool off.