TPR Drain up and out of crawl space???

[William Warner]

Originally Posted by rray

Actually, some PVC will. Most PVC here has the temperature and pressure ratings printed on the pipe.

Yes, and most often lower than the TPR release rating.

[Russel Ray]

Originally Posted by wwarner

Yes, and most often lower than the TPR release rating.

I'll have to disagree with that. Many people, including myself, have found that the better PVC with the higher ratings is not significantly more expensive that the lower-quality stuff, and the thicker pipe means fewer breaks and other problems over the long run, so that small initial increase is earned back very, very quickly. When I do find PVC used as TPR drain pipes, it's always the better grade stuff with the higher temperature and pressure ratings. And there also are many jurisdictions in my area that have no problem with PVC for TPR drain pipes under the premise that the drain pipe doesn't have to take the pressure and/or temperature for an extended period of time since it has an open end.

[William Warner]

Originally Posted by rray

I'll have to disagree with that. Many people, including myself, have found that the better PVC with the higher ratings is not significantly more expensive that the lower-quality stuff, and the thicker pipe means fewer breaks and other problems over the long run, so that small initial increase is earned back very, very quickly. When I do find PVC used as TPR drain pipes, it's always the better grade stuff with the higher temperature and pressure ratings. And there also are many jurisdictions in my area that have no problem with PVC for TPR drain pipes under the premise that the drain pipe doesn't have to take the pressure and/or temperature for an extended period of time since it has an open end.

CPVC (melon or tan in color) is rated for 100 psi at 180 degrees F.
PVC (white in color) is rated at 73 degrees F. (not sure of psi)

The TPR on my water heater is set for 150 psi and 210 degrees F.

Yes many jurisdictions allow CPVC. I just feel it's better and safer to install copper for only a couple monkeys ($) more. After all, what is the price on safety?

I simply picture a noodle in boiling water when it comes to plastic and high temps.

[Michael R. Boyett]

http://www.ppfahome.org/products.html

[Russel Ray]

Originally Posted by wwarner

CPVC (melon or tan in color) is rated for 100 psi at 180 degrees F.
PVC (white in color) is rated at 73 degrees F. (not sure of psi)

The TPR on my water heater is set for 150 psi and 210 degrees F.

Yes many jurisdictions allow CPVC. I just feel it's better and safer to install copper for only a couple monkeys ($) more. After all, what is the price on safety?

I simply picture a noodle in boiling water when it comes to plastic and high temps.

In a quick trip outside in the pouring rain and 30 mph winds to my irrigation pile, I found Schedule 40 PVC rated at 125 psi, 310 psi, and 600 psi, and temperature ratings from 73°F to 210°F. The higher psi rating goes with the higher temperature rating.

Many jurisdictions here allow both PVC and CPVC, irregardless (love that word) of color.

[Russel Ray]

Originally Posted by mboyett

http://www.ppfahome.org/products.html

From that site (useful site, by the way; thanks):

Other PPFA Products: ABS | Cements | CPVC | Fittings | PE | PEX | PVC | TIPS

GENERAL
Polyvinyl Chloride (PVC) piping is the most widely used plastic piping material. PVC piping systems are:

• Environmentally sound.
• Provide long service life.
• Easy to install and handle.
• Corrosion resistant.
• Cost effective.
• Widely accepted by codes.

PVC pipe is manufactured by extrusion in a variety of sizes and dimensions and generally sold in 10' and 20' lengths. PVC pipe is available in both solid wall or cellular core construction. Cellular core construction involves the simultaneous extrusion of at least three layers of material into the pipe wall: a solid outer layer, a cellular core intermediate layer, and a solid inner layer. PVC pipe is made to conform to various ASTM standards for both pressure and non-pressure applications.

USES/APPLICATIONS
PVC piping is used for:

• Drain-waste-vent (DWV).
• Sewers.
• Water mains.
• Water service lines.
• Irrigation.
• Conduit.
• Various industrial installations.

It can be used under ground or above ground in buildings. It can also be used outdoors if the pipe contains stabilizers and UV inhibitors to shield against ultraviolet radiation and it is painted with a water-based latex paint.

PVC materials are resistant to many ordinary chemicals such as acids, bases, salts and oxidants.
Because PVC piping system components can be manufactured in a variety of colors, identification of application is easy. A common color scheme (although not universal) is:

• White for DWV and some low pressure applications.
• White, blue, and dark gray for cold water piping.
• Green for sewer service.
• Dark gray for industrial pressure applications.

This color scheme has an exception in that much of the white PVC pipe is dual rated for DWV and pressure applications.

PVC piping systems should not be used to store and/or convey compressed air or other gases. PVC piping systems should not be tested with compressed air or other gases either. CODE STATUS
PVC piping is recognized as acceptable material for DWV, sewers, and potable water services and distribution in all model plumbing codes. These Codes normally identify acceptable products for specific uses based on the ASTM Standard designation.

[William Warner]

I guess a comparison between the TPR ratings and the in use PVC ratings should be made then before calling them out. All CPVC that I have seen including what is in my house and new construction is rated at 100 psi at 180 degrees F. I just checked a new stick of 1/2" I recently purchased and it is the same rating. I guess the better quality stuff hasn't made it our way yet. Until then, I'll keep calling out the lesser rated CPVC and PVC regardless of jurisdiction allowances. I personally don't feel it's safe and will at least alert my clients to it. Let them make their own decision.

[Russel Ray]

Originally Posted by wwarner

. . . PVC . . . CPVC

They are two different materials. I don't believe they are interchangeable. I have no experience with CPVC. I did read the link above about both PVC and CPVC, so I do now have a little knowledge about CPVC.

[William Warner]

Originally Posted by rray

They are two different materials. I don't believe they are interchangeable. I have no experience with CPVC. I did read the link above about both PVC and CPVC, so I do now have a little knowledge about CPVC.

Very true and I am guilty of using them interchangibly as are many others.

CPVC is what is used mostly around here for plumbing pruposes. It is very inexpensive and easy to use. I don't have issue with it's general use, just use as a TPR drain line.

p.s.
I did'nt intend for you to go get wet on my account.

[William Warner]

Originally Posted by mboyett

http://www.ppfahome.org/products.html

That is a very good site. Thanks for the referance!

[Russel Ray]

Originally Posted by wwarner

CPVC is what is used mostly around here for plumbing pruposes. It is very inexpensive and easy to use. I don't have issue with it's general use, just use as a TPR drain line.

Considering that the TPR drain line typically would only have to take a short burst (five gallons is what I generally hear plumbers use) of high pressure, high temperature water because it has an open end, and because it is sooooooooooo easy to change, the type of material that the TPR drain line is made out of is one of my least concerns. I will always call out unapproved materials, but the TPR drain line doesn't rank anywhere at all on my list of major concerns that I find during a home inspection, unless it's currently plugged. The mud wasps like to create homes in the ends of the drain lines here.