CPVC pipe, what is that?

[Walter R.]

I am installing a new water heater in my garage. Code requires that the drain from the pressure relief valve to the outside of the house be "galvanized steel, or hard drawn copper pipe or CPVC". (They stopped allowing the drain to terminate on the garage floor.)

I am used to working with # 40 PVC irrigation pipe. What is this CPVC stuff? Does HD sell the pipe and also the fittings? Do I use regular PVC cement? I have to run about 5' vertical and 12' horizontal.

Should I stick to 3/4" sweated copper pipe, although copper is kind of expensive and harder to work with ?

Thanks for your help

[Rich]

Clorinated Poly Vinyl Chloride. It has a higher melting point that PVC so it can be used for hot and cold water runs.

USES/APPLICATIONS CPVC piping which is suitable for hot and cold water distribution has a 400 psi pressure rating at room temperature, and a 100 psi pressure rating at

180 F.

Rich

[Ralph Mowery]

HD sells the CPVC. It is similar to the pvc pipe and should be located close to it. It uses glue similar, but not the same as pvc.

[Harry K]

Rich is correct. It is rated for hot water service, slightly different color than PVC, takes a different glue and is sized so pvc and cpvc fittings and pipe cannot be intermixed.

At one time there was IIANM a glue that could be used on either but I haven't looked in at least 20 years.

Harry K

[S. Barker]

Same glue works.

s

[Doug Miller]

Chlorinated polyvinyl chloride -- similar to PVC, but tolerant of higher temperatures. PVC pipe is not rated for use with hot water under pressure; CPVC is.

Yep.

Nope.

You need cement that's rated for use with CPVC. Most cements sold for use with PVC can be used with CPVC also, but not all. Check the label. You want one that's labelled for both.

That's totally up to you, depending on your budget, your skill level at sweat-soldering copper pipe, and whether you prefer the appearance of copper or plastic.

[Harry K]

Much too broad a statement. SOME glues will work on both, some won't. Last can I bought (which is not that old) specifies "PVC Pipe Cement". It is 'Christy's "Red Hot Blue Glue"

If it doesn't say CPVC on the label, don't use if for that or you WILL have failed joints. I have been using both CPVC and PVC since 1976 so I do have experience reading both labels and 'home repair' articles.

Harry K

[Harry K]

Budget is a big one. CPVC fittings and pipe are a pittance compared with copper.

Harry K

[Ralph Mowery]

Go with the cpvc pipe. This is just for the relief valve and hopefully it will never relief. It should be open on one end and not have too much pressure on the joints. Much cheeper and easier to work with. Even if the joints fail, most likely if you are not around to get burnt, the most dammage will be just water damage.

[S. Barker]

Well _I'VE_ NEVER personally seen a can of cement that did not include both pvc, cpvc, abs and all the others. Of course, i only use the name brand cements and not this off the wall stuff you mentioned....

s

Much too broad a statement. SOME glues will work on both, some won't. Last can I bought (which is not that old) specifies "PVC Pipe Cement". It is 'Christy's "Red Hot Blue Glue"

If it doesn't say CPVC on the label, don't use if for that or you WILL have failed joints. I have been using both CPVC and PVC since 1976 so I do have experience reading both labels and 'home repair' articles.

Harry K

[JC]

I don't think Oatey is off the wall and they have several different types all listed on the cans.

[Red]

Hold on a minute. Have you noticed HD & Lowes has CPVC that is labeled by the manufacturer as 'cold only'? Of course it's mixed in with all the other CPCV so most do not notice the label. That brings on many questions.

Red

[Doug Miller]

My guess would be you haven't been reading the labels too carefully. *Most* PVC cements are *not* labelled for use with CPVC, let alone ABS. Look around the next time you're at Lowes or HD, and you'll see what I mean.

[Harry K]

Then you haven't seen many brands of it. BTW Christy is only one of the major manufacturers of it. They put out more different glues than just 'Red Hot Blue Glue'

Harry K

[Harry K]

I'd like to check that but we don't have either in my immediate vicinity. Do you have a cite for it?

Harry K

[S. Barker]

I stand as stated. All the oatey cements i looked at were good for all the items i mentioned. And i have been to Lowes and HD. I live there. I'm in the process of replumbing a house some dumass stole all the copper out of.

s

[JC]

If you're willing to look at an attachment, I'll scan in a couple of can labels and you can see for yourself.

[S. Barker]

Send away. I don't really see the point however.

s

[Harry K]

Of course not. You made an erronious post and now refuse to back down. You look at a few cans of ONE brand and apparently it was a very limited selection from that brand at that. There is proof all over the net and an honest look at the glue shelf in any decent hardware store will show that you are in error.

Harry K

[JC]

Well, if there's no point, I guess I just misread your admonsion. I'll go on without you.

PLONK