CPVC leaks

[Fred Herndon]

I'm hoping someone here has some answers to this. I got a call this afternoon from a customer I inspected for last year. Since moving into the home he has had multiple leaks from joints in CPVC water lines. The house is 11 years old and on city water supply. The pictures show one of the leaking fittings that was replaced, a repair to supply lines to the whirlpool tub and the living room ceiling underneath. There have been at least 3 other leaks, all between the first and second floors of the house, and another new one is starting to come through the breakfast room ceiling now. This has gotten so bad he turns off the water before they leave for work each day, probably a smart move.

I looked in the crawl space just to be sure and there was no evidence of leakage or repairs underneath. Piping in the crawl space is the Crestline Flowguard Gold, but piping observed under the whirlpool is a similar looking product manufactured by Charlotte Pipe. Has anyone heard of any defective pipe or glues? I am assuming both brands of pipe use the same adhesives, and it looked like there was plenty of primer where I could see.

Water temperature measured 135 degrees, pressure measured 75 psi, both within acceptable operating ranges of the pipe (100 psi @180 degrees). Ideas????

[James Duffin]

Looking at the first picture...there is a hole between the pipe and the fitting at the top of the elbow. It looks like they did not twist the pipe when it was inserted in the fitting. Also the globs of glue looks like the glue may have been old/thick and did not flow properly. I would take a hack saw and cut the elbow in half longways so you can see how well the glue is spread out inside the fitting.

[Rick Hurst]

Just by the looking at the destruction of the wood support in the second picture tells you what kind of Plumber did the work.:eek:

[Robert Foster]

Details matter....I agree with the sloppy work/ old glue/ no twist diagnosis above.

[Dom D'Agostino]

Probably poor workmanship or improper procedures. Someone used skinned-over cement, partially evaporated cement, let it puddle in the joints, pressurized the system prematurely, etc. etc.

I'd replumb the house with those problems.

[Bruce King]

Along with the possible bad glue job they may have used that spa tub several times which leaves the water heater full of cold water that expands during the reheat cycle. If a thermal expansion device was not present and no one used a fixture during the reheating cycle the pressure would have gone over 200- 300 psi easily.

[James Duffin]

Most of the water heaters I have seen have relief valves set at 150 PSI. Hopfully that would have kept the pressure at 150 or below.

[Fred Herndon]

Looking at the first picture...there is a hole between the pipe and the fitting at the top of the elbow. It looks like they did not twist the pipe when it was inserted in the fitting. Also the globs of glue looks like the glue may have been old/thick and did not flow properly. I would take a hack saw and cut the elbow in half longways so you can see how well the glue is spread out inside the fitting.

Yes, I saw that. Cutting the fitting longways is a good idea, just to see what kind of glue distribution they have. What gets me, though is that the house is 11 years old. You would think these problems would have showed up long before. Also, everything is on the second floor, no problems in the crawl space.

One thing I read about CPVC is that it expands much more than other piping materials when it is hot. If it is clamped too tight, or there is no room for expansion, bad things can happen. Expansion because they had the water temperature set too high, coupled with defective glue joints could be the problem. When we were in the crawl space we could hear the pipe "popping" at the support clamps as it shrunk back to size. Their plumber was to come out and look at it again today. I am interested to see what he says.

[David Bell]

The color of the cement looks like all purpose was used. Given the way that and the primer are applied, a plumber having a seizure may have installed it. The tub was fixed once or replaced. Shark Bite fittings used to transition to pex.

[Fred Herndon]

Yes, the tub was fixed last week after it leaked and ruined the living room ceiling. Now they have a new one (leak, that is). Ceiling to be replaced after framing dries out.
This house has been jinxed as far as water is concerned. Since moving in a year ago he as replaced the water heater, repaired 4-5 leaks from the CPVC, replaced the pull stop water cutoffs for a bath vanity that leaked (see below) and the drip pan on his new refrigerator leaked onto the oak floors in the kitchen.
The only sign of a leak at the inspection last year was a small water stain under the upstairs hall bath. The sellers said it was water leaking around the shower controls and had been repaired. Turned out the fitting I showed in the first picture was the problem. Luckily he has a home warranty, but they still charge him $50.00 per trip.

[John Kogel]

I have never seen that degree of failure with CPVC. The correct glue is a solvent the welds the fittings to the pipe. Unbreakable. I have used it successfully without any primer, although not in recent years. I agree with the others, bad glue and a major change in pressure is occurring. An expansion tank may help, but none of those fittings are trustworthy at this point.

Replace all with PEX.

[Bruce King]

Was that PEX already present at the spa tub?
Looks like some PEX may have been glued to CPVC before where the sharkbite connectors now are.
The first picture also may have some white PEX for that right section with no lettering present. Look at the clean edge where it was cut, cpvc does not cut that cleanly.

I found some white PEX glued to CPVC a few weeks ago, its not as easy to recognize as you would think.

[Garry Sorrells]

Possible scenario, real case. CPVC being installed by plumber apprentice. Failed to hold glued joint together till glue set. Joints backed apart. Glue held water for a year. Then leaks started. First with most used lines. Chased leaks, ended replacing all lines. Did cut apart failed joints to see problem.

[Fred Herndon]

Was that PEX already present at the spa tub?
Looks like some PEX may have been glued to CPVC before where the sharkbite connectors now are.
The first picture also may have some white PEX for that right section with no lettering present. Look at the clean edge where it was cut, cpvc does not cut that cleanly.

I found some white PEX glued to CPVC a few weeks ago, its not as easy to recognize as you would think.

Bruce,
The Pex you see under the tub is part of the repair done by the warranty company's plumber. I can verify that it was all CPVC originally because I can see the pipe it was cut from. Good idea, though. I have referred him to a plumber I have known for several years for a second opinion, so if we find out anything I will let you know.

[Fred Herndon]

Possible scenario, real case. CPVC being installed by plumber apprentice. Failed to hold glued joint together till glue set. Joints backed apart. Glue held water for a year. Then leaks started. First with most used lines. Chased leaks, ended replacing all lines. Did cut apart failed joints to see problem.

Garry
Sounds plausible, judging from the overall sloppiness of the work. Only problem is the house is 11 years old. Why did it take so long to show up?

[Garry Sorrells]

Fred
I would think it was just the time required for the expansion and contraction to work on the fittings, could have been 5 years or 19yrs The glue is supposed to stay a little flexable to compensate for the contraction and expansion. Why do some people have a heart attack at 35 an others at 85, predisposition of the plumbing.

I have had discussions with plumbers about their opinion that the joints receive shocks from the water and they have the fear that those pressure shocks will over time cause the joints to fail. There fore they prefer to use copper to prevent the joint failure.

Many opinions many people.

[Jeff Zehnder]

Fred,

Another piece of information that you may already be aware of... CPVC pipe tends to become brittle over time and cracks more easily if there are any adverse conditions present. I don’t know if this is particular to NC but IO have experienced this a few times over the last few years.

[Ken Zapen]

Not gonna happen. The T/P valve on the water heater will go off at 150PSI. The T/P valve is not a thermal expansion device. If the potable water distribution system lacked BOTH a T/P valve on the water heater and a thermal expansion valve/tank, then the static pressure could go above 150 PSI.

Failures on CPVC caused from thermal expansion usually occur at or near the heater. The pipe usually expands under the heat and pressure (mainly the pressure) and it looks like and inflated balloon. Some times little hernias just balloon out by themselves.

I don't see any evidence of damage from thermal expansion in the photos.


Along with the possible bad glue job they may have used that spa tub several times which leaves the water heater full of cold water that expands during the reheat cycle. If a thermal expansion device was not present and no one used a fixture during the reheating cycle the pressure would have gone over 200- 300 psi easily.

[Ken Zapen]

Fred, how exactly are the leaks occurring? Are the fittings themselves cracking? Is the pipe cracking right at the line of glue as it enters the fittings? Are there random cracks occurring along straight lengths of pipe? Is the pipe "ballooning" up and bursting? Is the pipe just pulling out of the fitting hubs? Each type of failure indicates a specific cause. The determine the cause of failure, I would need to know how the pipe/fittings failed.

[Bruce King]

Not gonna happen. The T/P valve on the water heater will go off at 150PSI. The T/P valve is not a thermal expansion device. If the potable water distribution system lacked BOTH a T/P valve on the water heater and a thermal expansion valve/tank, then the static pressure could go above 150 PSI.

Failures on CPVC caused from thermal expansion usually occur at or near the heater. The pipe usually expands under the heat and pressure (mainly the pressure) and it looks like and inflated balloon. Some times little hernias just balloon out by themselves.

I don't see any evidence of damage from thermal expansion in the photos.


The house is 11 years old, I bet it has the original water heater and original TPR valve which is probably frozen shut or badly out of calibraton at best.
Testing thermal expansion pressures starting with a cold tank and zero water usage during the test is not advised but can be done for enlightment.

[Ken Zapen]

It's possible. If the system has a backflow preventer on the water service and/or a PRV without a bypass mechanism built it and the T/P has built up with galvanic cell corrosion and there is no thermal expansion device (working bladder tank or pressure relief valve) it could happen.

In that case, the pipe will tend to swell up and burst at or near the water heater due to the pressure de-rating of the pipe from heat.


The house is 11 years old, I bet it has the original water heater and original TPR valve which is probably frozen shut or badly out of calibraton at best.
Testing thermal expansion pressures starting with a cold tank and zero water usage during the test is not advised but can be done for enlightment.

[Bill Hetner]

Hi, I have seen posting on here that refers back to the water pressure in the system. I have installed a whirpool bath and it has no bearing on the water pressure in the plumbing system! it has it's own pump which takes water from the tub and pressurizes it and is a closed system. Water temp is something that a average person can stand with out being scalded saying water temp is full blast on and at 135dreg is usually not right. who has a bath at that temp?? not me I like my skin on. this is a whirpool bath it is a closed system once water is in there, the closed system takes over and then it drains out. there is a possiblity of a heater on the unit but the regular water pressure in the regular plumbing system is not used in the whirpool bath. These systems are factory tested and then shipped out. if they get banged around or leaks develop that is a closed system that has to be dealth with. the piping on this unit may be old and defective but has no bearing on the rest of the plumbing. deal with it as a separate system.
fyi imo

[Bruce King]

Hi, I have seen posting on here that refers back to the water pressure in the system. I have installed a whirpool bath and it has no bearing on the water pressure in the plumbing system! it has it's own pump which takes water from the tub and pressurizes it and is a closed system. Water temp is something that a average person can stand with out being scalded saying water temp is full blast on and at 135dreg is usually not right. who has a bath at that temp?? not me I like my skin on. this is a whirpool bath it is a closed system once water is in there, the closed system takes over and then it drains out. there is a possiblity of a heater on the unit but the regular water pressure in the regular plumbing system is not used in the whirpool bath. These systems are factory tested and then shipped out. if they get banged around or leaks develop that is a closed system that has to be dealth with. the piping on this unit may be old and defective but has no bearing on the rest of the plumbing. deal with it as a separate system.
fyi imo

Bill, different subject, I was referring to the pressure that builds up when a cold water heater is heated up with no fixtures being used. The spa tub was only mentioned because that is the most typical item that will use up all of the hot water in the tank and cause the most thermal expansion.

[Bill Hetner]

Hi Bruce I have no arguement with your posting about the hot water tank, I just saw the whirpool tub pictures and got off track about the leaks. I still stand behind what I said about the tub but apon rereading the op thread realize there were other leaks in the house in other places. Seems like the owner needs to reassess the plumbing connections and get some good qualitfied help in redoing the lines. the shark bite connections are expensive route to take but I have used them too. A system you can't trust is a system you don't want even when you are there.

[Fred Herndon]

Fred, how exactly are the leaks occurring? Are the fittings themselves cracking? Is the pipe cracking right at the line of glue as it enters the fittings? Are there random cracks occurring along straight lengths of pipe? Is the pipe "ballooning" up and bursting? Is the pipe just pulling out of the fitting hubs? Each type of failure indicates a specific cause. The determine the cause of failure, I would need to know how the pipe/fittings failed.

Ken,
The leaks are occurring at the glue joints. No broken or ballooned pipe. The water heater was replaced this year, with a new thermal expansion tank. I am leaning strongly toward bad workmanship (letting glue skin over and/or not holding joints tight until glue sets), time and pipe expansion combining to cause the leaks.

More bad news last night: the new leak they found was from the shower pan, but when they cut open the wall to find it they found evidence of a previous repair. It is starting to look more and more like there have been problems in the past the seller "forgot" to tell anyone about.

Thanks to everyone here for the ideas. I have referred my client to a local plumbing contractor for a thorough evaluation of the system. If they figure this out I will let everyone here know.

FH

[Widdershins Saunders]

Ken,
The leaks are occurring at the glue joints. No broken or ballooned pipe. The water heater was replaced this year, with a new thermal expansion tank. I am leaning strongly toward bad workmanship (letting glue skin over and/or not holding joints tight until glue sets), time and pipe expansion combining to cause the leaks.

More bad news last night: the new leak they found was from the shower pan, but when they cut open the wall to find it they found evidence of a previous repair. It is starting to look more and more like there have been problems in the past the seller "forgot" to tell anyone about.

Thanks to everyone here for the ideas. I have referred my client to a local plumbing contractor for a thorough evaluation of the system. If they figure this out I will let everyone here know.

FH


Judging by the amount of cement puddled around the hubs of the fittings, I'd say the installer failed to bevel the edge of the piping before assembly.

Cutting CPVC with a wheeled cutter or even a shear cutter can leave an upraised, ridge on the pipe -- The ridge needs to be beveled, otherwise it will push the glue out of the hub of the fitting during assembly.

Ridgid and a few other trade related companies make a coned deburring tool that eliminates this upraised ridge.

[Mike Clarke]

Looks like wrong glue type was used.
CPVC if installed correctly will last a long time, I have never had leaks with installation that is over 30-years now, not even close to being brittle.
I even installed in a green house hot bed under sand using hot water system in a closed loop system (Wish I had pex then). Pulled it out recently and was still in good shape.

As for the pressure, I think 75psi at the house would be a little on the high side, I usually do not like to be over 55. may want to check and make sure a proper working regulator and surge tank is installed, usually around the cold side of the hot water tank, this will keep back pressure from the hot water expansion from blowing out pipes.