Plumbing glue: Educate me
#1
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Thread Starter
Plumbing glue: Educate me
I didnt know there were so many glues, primers & cleaners.
I got home to a water leak outside. Dug up the area & found it was a PVC connection that had come apart. So, I went to the shop grabbed the few PVC plumbing repair items I had & figured this would be a simple fix..... except, the glue I had was dried up. So, made a flying trip to the hardware store across town & found greens, purple & yellow labels. I found Cleaner (that I know to about), primer (that I dont know about) & then the different glues. I grabbed the familiar green label PVC glue & a can of cleaner & out the door (well, I did stop to pay for it).
I did notice there was CPVC (?) glue. Then primer that I think was optional in various colors (purple was one) the cleaners. Then cleaner.
Any of you teachers want to educate me (us) on the differences & uses? (I dont know about primer specifically)
I got home to a water leak outside. Dug up the area & found it was a PVC connection that had come apart. So, I went to the shop grabbed the few PVC plumbing repair items I had & figured this would be a simple fix..... except, the glue I had was dried up. So, made a flying trip to the hardware store across town & found greens, purple & yellow labels. I found Cleaner (that I know to about), primer (that I dont know about) & then the different glues. I grabbed the familiar green label PVC glue & a can of cleaner & out the door (well, I did stop to pay for it).
I did notice there was CPVC (?) glue. Then primer that I think was optional in various colors (purple was one) the cleaners. Then cleaner.
Any of you teachers want to educate me (us) on the differences & uses? (I dont know about primer specifically)
#2
Group Moderator
I hope you also bought and used primer. Cleaner is an optional step but priming is required.
Purple primer is required by code for connections made in the home and mains connecting it to the meter. The purple color is so inspectors can verify that primer was used before gluing the joints. Clear primer is also available but it shouldn't be used on things needing a inspection so it's most often used for air lines and irrigation systems out in the yard.
Purple primer is required by code for connections made in the home and mains connecting it to the meter. The purple color is so inspectors can verify that primer was used before gluing the joints. Clear primer is also available but it shouldn't be used on things needing a inspection so it's most often used for air lines and irrigation systems out in the yard.
#3
Forum Topic Moderator

CPVC glue can only be used with CPVC. They do sell one can of glue that can be used for both CPVC and PVC. I rarely use primer and have never noticed any difference between the joints that were primed and those that were not. AS PD stated - most inspectors want to see the primer [if it needs to be inspected]
I don't know why but it seems like the glue dries up in the can quicker than it used to. ... and locally they quit selling the small cans.
I don't know why but it seems like the glue dries up in the can quicker than it used to. ... and locally they quit selling the small cans.
#4
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Thread Starter
Thanks for the response PD. Obviously, I am no plumber. I did not use primer. I didnt even know what primer is or what its used for. The little bit of plumbing I have done, I've just always used a cleaner, then glue. Now I know to use it from this point forward.
I understand that purple primer is for visual inspection but does it serve any other purpose?
So, you're saying my procedure should have been to use cleaner, then primer, then glue.
My 1st thought was, purple primer is going to get on my clear glue "mop" then get in my glue can from the mop. Is this going to happen or does primer dry pretty quick? What should I expect?
I understand that purple primer is for visual inspection but does it serve any other purpose?
So, you're saying my procedure should have been to use cleaner, then primer, then glue.
My 1st thought was, purple primer is going to get on my clear glue "mop" then get in my glue can from the mop. Is this going to happen or does primer dry pretty quick? What should I expect?
#5
Group Moderator
Thread Starter
Mark, I am only familiar with PVC. Just white pipe for plumbing water lines. Whats the differents? Anything I need to know about that?
Maybe CPVC is the gray electrical plastic pipe?
Maybe CPVC is the gray electrical plastic pipe?
#7
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I’m no expert so see what the other guys say, but I believe the primer sets up and softens the pvc so it is ready for the glue (well really it’s a solvent but we all call it glue). So you use the primer and then the glue right after that.
That’s what I do and I haven’t had any problems.
CPVC for the home I believe is usually white (or cream color) and has a yellow stripe on it and can be used for hot water in the house. Home Depot Lowes etc carry it. PVC can’t be used for hot water.
That’s what I do and I haven’t had any problems.
CPVC for the home I believe is usually white (or cream color) and has a yellow stripe on it and can be used for hot water in the house. Home Depot Lowes etc carry it. PVC can’t be used for hot water.
#8
Forum Topic Moderator
My house is plumbed with cpvc. Most plumbers don't like it but it works well for a dummy like me. It goes together just like regular pvc except the fittings are slightly different. As mentioned above cpvc can handle hot water while pvc can not. cpvc is off white and it's made so you can't accidentally use pvc fittings. The cpvc I'm used to has blue lettering and no stripe - might be brand dependent.
#9
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Yep you're right. Charlotte pipe has the yellow strip, but Home Depot also has Genova CPVC pipe which doesn't have the stripe - just blue lettering. My bad, it all doesn't have a stripe. Good to know.
#10
I don't know why but it seems like the glue dries up in the can quicker than it used to. ... and locally they quit selling the small cans.
#11
#13
Forum Topic Moderator
I read an engineering study a while back about PVC cement and whether primer is needed based on shear strength after it cured.
Basically the result was if the pipe is clean, dirt/grease removed, the glossy finish removed slightly - use of a primer didn't significantly add to the strength. But, on a construction site, we all know no one takes the time to clean the PVC before cementing it. So trying to use just cement on a dirty pipe, resulted in low strength connections.
This is the reason for most inspectors requiring the use of primer, it helps ensure the pipe is clean enough for the solvent/cement to actually 'melt' the plastic and make a secure bond.
Separately, from Oatey's website:
The most commonly accepted 'correct' method for joining PVC is:
* Manually clean the pipe (with a rag, rarely with 'cleaner')
* Apply primer (usually purple)
* Wait for the primer to look dry, but not long enough for it to actually dry out (less than 5 min)
* Apply cement (solvent) to both sides of the connection
* Make the connection and hold until it sets.
Basically the result was if the pipe is clean, dirt/grease removed, the glossy finish removed slightly - use of a primer didn't significantly add to the strength. But, on a construction site, we all know no one takes the time to clean the PVC before cementing it. So trying to use just cement on a dirty pipe, resulted in low strength connections.
This is the reason for most inspectors requiring the use of primer, it helps ensure the pipe is clean enough for the solvent/cement to actually 'melt' the plastic and make a secure bond.
Separately, from Oatey's website:
Can you use cleaner instead of primer?
No. Cleaner is only designed to remove surface dirt and grease from the pipe where as primer actually starts the chemical reaction needed to bond the pipe and fittings together.
No. Cleaner is only designed to remove surface dirt and grease from the pipe where as primer actually starts the chemical reaction needed to bond the pipe and fittings together.
* Manually clean the pipe (with a rag, rarely with 'cleaner')
* Apply primer (usually purple)
* Wait for the primer to look dry, but not long enough for it to actually dry out (less than 5 min)
* Apply cement (solvent) to both sides of the connection
* Make the connection and hold until it sets.
#15
Actually the recommended method for priming and gluing is to apply the glue to the material before the primer dries.
When I repaired my spa last year I called a couple of glue/solvent suppliers to inquire because I read that and never did it that way and absolutely wanted it done correctly, they all agreed.
1) For primed joints only, apply a coat of primer around the outside of the pipe and the inside of the fitting. While the primer is still wet, immediately proceed to step 2.
2) Apply a coat of cement around the outside of the pipe and the inside of the fitting.
3) Push the two pieces together and twist 90°. Hold the joint for 15 seconds to ensure that the pieces do not slide apart.
When I repaired my spa last year I called a couple of glue/solvent suppliers to inquire because I read that and never did it that way and absolutely wanted it done correctly, they all agreed.
1) For primed joints only, apply a coat of primer around the outside of the pipe and the inside of the fitting. While the primer is still wet, immediately proceed to step 2.
2) Apply a coat of cement around the outside of the pipe and the inside of the fitting.
3) Push the two pieces together and twist 90°. Hold the joint for 15 seconds to ensure that the pieces do not slide apart.