Cure Time For CPVC "Glue?"

[MuddlingThru]

I have to add a section of pipe to both my hot and cold lines on Friday for a bathroom remodel. I was wondering what the consensus of all of you experts is as to how long after I glue the new CPVC pipe to the old before I pressure the system back up. Also, would it be any longer for hot than cold? I was thinking in terms of several hours to be safe, but I am curious what you pro's think.

 

[Finnegan]

I do not know what the recommended cure time is, but I have had the water back on in about 10 minutes with no trouble.

 

[Sponsor]

 

[Jimbo]

Not familiar with CPVC glue. The can will probably say "allow to cure complely before use." That varies a lot with temperature.

PVC "hot" blue glue can be used to 70 PSI with an hour ( usually much less!)

 

[Finnegan]

I have never used hot or blue glue. I take it it is different from regular clear pvc cement? The clear sets up pretty quickly. I can't imagine wanting something that sets up faster.

 

[MuddlingThru]

I'm using the Flowguard Gold CPVC glue. I thought maybe a couple of hours, but perhaps I could get by with an hour if I'm running out of time.

The reason I'm asking is that I read somewhere recently (can't find it now) someone complaining that he preferred copper over CPVC because he could have water back on in minutes versus CPVC where he had to wait for up to five hours! I thought that was a little ridiculous, but the guy was a certified plumber. Heck, I prefer copper too for the same reason, but my house was repiped to CPVC a little over a year ago because water is very aggressive on copper down here. No one uses it anymore.

 

[hj]

cpvc

CPVC glue is usually a yellowish color. You cannot use clear, blue, or any other PVC glue on CPVC.

 

[Cass]

If you read the fine print on the back of the can it will tell you.

I think it mentions a couple of hours, not positive.

While I don't use it, what what I gather is if you glue on the hot side and then use it under pressure it may pop out if the solvent has not evaporated by adding heat and pressure while it is soft.

 

[Jimmym]

I have to add a section of pipe to both my hot and cold lines on Friday for a bathroom remodel. I was wondering what the consensus of all of you experts is as to how long after I glue the new CPVC pipe to the old before I pressure the system back up. Also, would it be any longer for hot than cold? I was thinking in terms of several hours to be safe, but I am curious what you pro's think.

I just replumbed with FlowGuard Gold too. Way too easy. I'll never use copper again if I can avoid it.
There are 2 methods of joining. Primer and Cement or One-Step.
The Primer you use is either clear or purple. The solvent cement for CPVC is ORANGE.
The One-Step cement (by FlowGuard) is yellow.
You can pressure test @100 PSI using the One-Step cement in about 10-15 min.

See this link.
http://www.flowguardgold.com/Guides/FGGdesign.pdf

Don't let anyone kid you. This stuff is strong. I read that during a test on 1/2" FlowGuard Gold. The pipe ruptured before the joint failed. That was at ~1600 PSI, if I remember correctly.

 

[Finnegan]

I have never used the one step, but it sounds like it performs just as well as two step. I have only used cpvc a few times, but it was very easy to work with. Cement is orange and a little thicker than clear pvc cement.

 

[Gary Swart]

Something many people either don't know or forget that this is not actually glue. CPVC like PVC and ABS are joined by chemically welding the materials together. The "glue" liquifies the surfaces of the pipe and the fitting briefly. You slide the pipe and fitting together and hold things in position for a few seconds while the surfaces fuse together. It takes a very short time for this to occur. While I wouldn't have someone with their hand on the valve to instantly return water to the line, you don't have to wait for a cure.

 

[Dunbar Plumbing]

Every container I've seen relating to CPVC and otherwise states the ability to AIR test after 2 hours and the mfg usually states 24 hours for water. I don't work with it much but every time I have to I tell the customer that I cannot turn the water on for at least 12-24 hours. They usually get another plumber at this point which is awesome. I'll keep my liability insurance right where I want it, unused.

 

[MuddlingThru]

I just replumbed with FlowGuard Gold too. Way too easy. I'll never use copper again if I can avoid it.
There are 2 methods of joining. Primer and Cement or One-Step.
The Primer you use is either clear or purple. The solvent cement for CPVC is ORANGE.
The One-Step cement (by FlowGuard) is yellow.
You can pressure test @100 PSI using the One-Step cement in about 10-15 min.

See this link.
http://www.flowguardgold.com/Guides/FGGdesign.pdf

Don't let anyone kid you. This stuff is strong. I read that during a test on 1/2" FlowGuard Gold. The pipe ruptured before the joint failed. That was at ~1600 PSI, if I remember correctly.

Thanks for the link. According to them, it will take between 10-30 mins for cure time, depending on ambient temp. I'll go the extra and wait a couple of hours. It does mention "increased cure time for hot water."

As to glue vs cement .. yeah .. I actually meant cement but was suffering from temporary brain asphyxia and couldn't think of the word "cement." Thus the reason I put "glue" in quotes.

BTW -- I've been using the purple primer throughout. The additional cost is negligible and I like the extra "insurance."

 

[Jimmym]

Thanks for the link. According to them, it will take between 10-30 mins for cure time, depending on ambient temp. I'll go the extra and wait a couple of hours. It does mention "increased cure time for hot water."

As to glue vs cement .. yeah .. I actually meant cement but was suffering from temporary brain asphyxia and couldn't think of the word "cement." Thus the reason I put "glue" in quotes.

BTW -- I've been using the purple primer throughout. The additional cost is negligible and I like the extra "insurance."

I used the purple primer and the orange cement. The Lowes didn't have the one step. I just used the purple so I wouldn't forget what I had primed and not primed.
No regrets, no leaks, no sweat (pun intended). They also say it's perfectly suited to hydronics. We'll see. I read that the original makers of CPVC just had a joint fail after being under 400 PSI for something like 30-40 years. I don't think longevity should be an issue. Oh, well. Happy plumbing!

 

[hj]

cpvc

I can't imagine how it would be "perfect" for hydronics. They even advise that a domestic hot water system not use a circualtion system, because it does not respond well to a constant hot temperature.

 

[Jimmym]

I can't imagine how it would be "perfect" for hydronics. They even advise that a domestic hot water system not use a circualtion system, because it does not respond well to a constant hot temperature.

Who says this? The documentation on the FlowGuard site says their product is just fine. I don't know how you run your hydronic system, but mine is 180 Deg Max at 20 PSI.

See page 18 of the PDF document listed above. Also, page 15 says it can be used for direct connections to water heaters as well. I don't know what you guys are worried about.

"FlowGuard Gold® pipe and fittings are ideal for both hot
water recycling systems and hydronic heat applications.
FlowGuard Gold® pipe and fittings are rated for
continuous pressure service of 100 psi at 180°F."

 

[Mikey]

Who needs cement?

I replumbed my house from under-slab copper to overhead CPVC using Oatey purple primer and Flowguard Gold pipe and one-step cement. Waited a day or two before pressure testing (air). Started at 60 PSI and it held fine for a few minutes, so I got frisky and cranked 'er up to 80 PSI. That lasted for about 5 seconds, when there was a loud explosion from the attic and the pressure dropped quickly to zero. I dashed upstairs and quickly found the problem -- one joint at a 3/4" valve that I had primed but neglected to cement (I had the pipe stuck in the valve for alignment purposes prior to cementing). I cemented it, waited another day, and tested everything at 100PSI for 3 days OK.

I'm sure there is at least one moral in this story.

 

[Jimbo]

temperature

I was not aware of the issue that you had to cure longer before pressurizing a glued pipe with HOT water.

I do know that cure time per se is related to the ambient temp. of the air, the pipe itself, and the glue. In very hot weather, you actually have to work very fast to put a joint together, as the cement on the pieces can start to gel quickly. If the weather is very cold, the cure time will be much longer.

I wish the manufacturers would put out a definitive chart of X temp, W PSI in X minutes. I think there are too many variables which they cannot control, so they play it safe and say wait "until it is cured" and don't tell you how long that is!

I agree with all the comments from the seasoned professionals. Lots of years of experience talking, and that's what counts.