Clear vs Purple Primer?

[Kengar]

I didn't see a better forum, so question is here.

Any difference in quality of the joint?

I'm going to be joining some schedule 80 that will be visible, so aesthetics are important. Oatey makes a medium gray cement, that should blend nicely, but I want to make sure the clear primer will be okay to use with it.

Thanks.

 

[Fritzhamer]

The purple is so that the building inspector can tell that the plumber used primer by visual inspection. Clear is fine to use.

 

[Kengar]

ahhhh. thanks. (wish they made a grey primer; didn't seem to see it)

 

[Fritzhamer]

There's grey. I think weld-on makes grey primer and grey glue/solvent.

 

[Big G]

Used clear on my last build. Worked great. Couldn't find it locally, had to order it through Amazon.

 

[Kengar]

There's grey. I think weld-on makes grey primer and grey glue/solvent.

I just checked, but don't find that they have grey primer. I'll go clear.

Thanks for replies

 

[Fritzhamer]

Yeah, here's grey cement but I don't see grey primer on Amazon either.

Weld-On 10121 Pint 711 Heavy Duty PVC Cement, Gray, 1-Pack https://www.amazon.com/dp/B00FIYR75O/ref=cm_sw_r_cp_api_jAk5zbF3ABRV4

I went with clear primer and cement on my build and it came out really well. I don't know that I'd trust the greys to perfectly match up. Clear is a pretty safe bet in terms of aesthetics.

 

[Brew12]

I didn't see a better forum, so question is here.

Any difference in quality of the joint?

I'm going to be joining some schedule 80 that will be visible, so aesthetics are important. Oatey makes a medium gray cement, that should blend nicely, but I want to make sure the clear primer will be okay to use with it.

Thanks.

Have you considered not using primer at all?

I regret using primer on my first system and will not be using it when I build my new system this winter.

Here is an interesting read.
https://www.plumbingsupply.com/the-great-pvc-primer-debate.html

If I had a basement build I might consider using primer on only the return but my plumbing is all under the tank.

 

[Idoc]

Have you considered not using primer at all?

I regret using primer on my first system and will not be using it when I build my new system this winter.

Here is an interesting read.
https://www.plumbingsupply.com/the-great-pvc-primer-debate.html

If I had a basement build I might consider using primer on only the return but my plumbing is all under the tank.

Interesting study... there's some question to the studies results since it was not conducted in a controlled environment, but our applications aren't in a controlled environment either... and actually more like how the examiner actually performed his tests! It's definitely a good case for skipping primer usage... especially in our low pressure systems!

 

[Fritzhamer]

I wouldn't trust joints without primer. You can join fittings with just primer. If anything you don't need the cement. The cement is there just to fill in any gaps.

Code requirements exist for a reason. PVC isn't a pressure rated pipe. Code requires primer for a reason. Most primer is purple because people misunderstand it's use and importance and skip it.

The inspector needs to be able to quickly notice such an error and say "what the heck!? You didn't use primer? You have to redo all of this."

 

[mfinn]

I didn't see a better forum, so question is here.

Any difference in quality of the joint?

I'm going to be joining some schedule 80 that will be visible, so aesthetics are important. Oatey makes a medium gray cement, that should blend nicely, but I want to make sure the clear primer will be okay to use with it.

Thanks.

I use clear primer on most joints, and I use clear glue on all joints. Why use a colored glue? Use clear and wipe the excess off for a clean looking build.

 

[Idoc]

I wouldn't trust joints without primer. You can join fittings with just primer. If anything you don't need the cement. The cement is there just to fill in any gaps.

Code requirements exist for a reason. PVC isn't a pressure rated pipe. Code requires primer for a reason. Most primer is purple because people misunderstand it's use and importance and skip it.

The inspector needs to be able to quickly notice such an error and say "what the heck!? You didn't use primer? You have to redo all of this."

Take a look at that study conducted in @Brew12 post above. It's a long read, but you can read the Introduction and then the Conclusions section and get the results of the study. Actual testing is showing opposite of what you are saying... the primed joints all failed before the non-primed joints. The point of the study is to see whether the codes need to be altered and adjusted. It would be interesting to see the studies/test data that were used to justify the current codes (if there were any).

 

[Brew12]

I wouldn't trust joints without primer. You can join fittings with just primer. If anything you don't need the cement. The cement is there just to fill in any gaps.

Code requirements exist for a reason. PVC isn't a pressure rated pipe. Code requires primer for a reason. Most primer is purple because people misunderstand it's use and importance and skip it.

The inspector needs to be able to quickly notice such an error and say "what the heck!? You didn't use primer? You have to redo all of this."

Yes, but even the 2015 IPC code doesn't require primer for piping under 4" in diameter. It may still be required by local code though.

I think it is important to understand the role of primer. The PVC glue has the exact same softening agent as the primer just in a less concentrated form. The primer provides a little more softening of the pipe. If you are making your joints in cold weather or on dirty or sun aged pipes primer is necessary. Prior to primer hitting the market the requirement was to use sandpaper on the pipe to prepare it. This exposed fresh pvc to ensure the glue had enough solvent to get a good bond.

I will also add that if you use CPVC you must use primer or a glue specifically designed not to use primer.

 

[Fritzhamer]

I here ya, Bill knows a thing or two about this as well. Interesting video from someone with decades of experience in building PVC run biological systems:
https://www.bulkreefsupply.com/vide...s-but-were-afraid-to-ask-macna-speakers-2017/

 

[Brew12]

I here ya, Bill knows a thing or two about this as well. Interesting video from someone with decades of experience in building PVC run biological systems:
https://www.bulkreefsupply.com/vide...s-but-were-afraid-to-ask-macna-speakers-2017/

I'll have to watch that tonight, I don't have access to videos here right now.

 

[Randy Holmes-Farley Verified Community Expert]

I prefer the purple look and coated the exposed white surfaces with it since it looks more like coralline and blends in better.