[submanx1]

Any plastic pipe that does not have an oxygen diffusion barrier, should not be used in a heating system that uses ferrous components. Lowering a systems operating temperature does not reduce the potential for oxygen permeability.

Don't know about the O2 barrier characteristics of the CPVC. Only know that CPVC with those ASTM ratings is specifically allowed in the code chapter 12 section 1202 table 1204.

[Mike45plus]

Cpvc has no O2 diffusion barrier, and, if it is used in hyronic applications that contain iron components , there will be corrosion...

[submanx1]

Here is the entire section

SECTION 1202 MATERIAL

1202.1 Piping. Piping material shall conform to the standards cited in this section.

Exception: Embedded piping regulated by Section 1209.

1202.2 Used materials. Reused pipe, fittings, valves or other materials shall be clean and free of foreign materials and shall be approved by the code official for reuse.

1202.3 Material rating. Materials shall be rated for the operating temperature and pressure of the hydronic system. Materials shall be suitable for the type of fluid in the hydronic system.

1202.4 Piping materials standards. Hydronic pipe shall conform to the standards listed in Table 1202.4. The exterior of the pipe shall be protected from corrosion and degradation.

TABLE 1202.4 HYDRONIC PIPE

MATERIAL

STANDARD (see Chapter 15)
Acrylonitrile butadiene styrene
(ABS) plastic pipe ASTM D 1527; ASTM D 2282
Brass pipe ASTM B 43
Brass tubing ASTM B 135
Copper or copper-alloy pipe ASTM B 42; ASTM B 302
Copper or copper-alloy tube
(Type K, L or M) ASTM B 75; ASTM B 88;
ASTM B 251
Chlorinated polyvinyl chloride
(CPVC) plastic pipe ASTM D 2846; ASTM F 441;
ASTM F 442
Cross-linked polyethylene/
Aluminum/cross-linked
Polyethylene (PEX-AL-PEX)
Pressure pipe ASTM F 1281;
CSA CAN/CSA-B-137.10


(continued)

TABLE 1202.4—continued—HYDRONIC PIPE

MATERIAL

STANDARD (see Chapter 15)
Cross-linked polyethylene
(PEX) tubing ASTM F 876; ASTM F 877
Ductile iron pipe AWWA C151/A21.51; AWWA C115/A21.15
Lead pipe FS WW-P-325B
Polybutylene (PB) plastic pipe
And tubing ASTM D 3309
Polyethylene/aluminum/polyethylene
(PE-AL-PE) pressure pipe ASTM F 1282; CSA B137.9
Polyethylene (PE) pipe, tubing
And fittings (for ground source
Heat pump loop systems) ASTM D 2513; ASTM D 3035;
ASTM D 2447; ASTM D 2683;
ASTM F 1055; ASTM D 2837;
ASTM D 3350; ASTM D 1693
Polypropylene (PP) plastic pipe ASTM F 2389
Polyvinyl chloride (PVC)
Plastic pipe ASTM D 1785; ASTM D 2241
Raised temperature polyethylene
(PE-RT) ASTM F 2623
Steel pipe ASTM A 53; ASTM A 106
Steel tubing ASTM A 254


1202.5 Pipe fittings. Hydronic pipe fittings shall be approved for installation with the piping materials to be installed, and shall conform to the respective pipe standards or to the standards listed in Table 1202.5.

TABLE 1202.5 HYDRONIC PIPE FITTINGS

MATERIAL

STANDARD (see Chapter 15)
Brass ASTM F 1974
Bronze ASME B16.24
Copper and copper alloys ASME B16.15; ASME B16.18;
ASME B16.22; ASME B16.23;
ASME B16.26; ASME B16.29
Ductile iron and gray iron ANSI/AWWA C110/A21.10
Ductile iron ANSI/AWWA C153/A21.53
Gray iron ASTM A 126
Malleable iron ASME B16.3
Plastic ASTM D 2466; ASTM D 2467;
ASTM D 2468; ASTM F 438;
ASTM F 439; ASTM F 877; ASTM F 2389
Steel ASME B16.5; ASME B16.9;
ASME B16.11; ASME B16.28;
ASTM A 420


1202.6 Valves. Valves shall be constructed of materials that are compatible with the type of piping material and fluids in the system. Valves shall be rated for the temperatures and pressures of the systems in which the valves are installed.

1202.7 Flexible connectors, expansion and vibration compensators. Flexible connectors, expansion and vibration control devices and fittings shall be of an approved type.

[Mike45plus]

Approval does not guarantee compatibilty! Spend some time tomorrow with technical support from US Boiler corp. Taco, or any other manufacturer of hydronic components, tell them you've been using cpvc on your installs, and I guarantee an eye opening learning experience for you...

[submanx1]

Approval does not guarantee compatibilty! Spend some time tomorrow with technical support from US Boiler corp., Taco, or any other manufacturer of hydronic components, tell them you've been using cpvc on your installs, and I guarantee an eye opening learning experience for you..........

I agree that mistakes can be made by anybody but... the code issuing organization is in my opinion is VERY to the point of overly conservative. Bottom line -- it is approved, I've been using it in this application for some time with no problems and intend to continue to do so. As for readers of this site they can evaluate the pros and cons for themselves. If they choose to use it and they get hassled by code officials they can point to the section of the code that allows it.

[Mike45plus]

There is a website that I frequent, Heatinghelp.com, it is a community of the most knowledgeable heating professionals in the world, who are very willing to share their expertise. I doubt that you will continue to challenge the laws of physics after spending some time there...

[submanx1]

There is a website that I frequent, Heatinghelp.com, it is a community of the most knowledgeable heating professionals in the world, who are very willing to share their expertise. I doubt that you will continue to challenge the laws of physics after spending some time there..........

I'll go there and thanks for the tip. Your comments have piquéd my interest in the potential O2 issue. BTW I have a BS in Physics and Math and 33 year career as a Physicist.

[Mike45plus]

The information available at the heating help website will be of great interest to you, as will the discussions regarding 02 permeation and the ensuing DIN standards, that I believe were developed by a consortium of German physicists. By the way, I'm only a plumber, how much could I know...

[submanx1]

The information available at the heating help website will be of great interest to you, as will the discussions regarding 02 permeation and the ensuing DIN standards, that I believe were developed by a consortium of German physicists. By the way, I'm only a plumber, how much could I know..............

Just responding to your physics comment. Did not intend to disregard your experience. Haven't gotten to Heating help yet but a review of the Charlotte Pipe web site indicates that CPVC can be used in Hydronic systems as long as the operating temps and pressures are not exceeded and providing that the pipe is properly installed. The O2 issue is not addressed in the tech lit that I reviewed.

[massplumber2008]

Don't worry guys, I have more undergrad and graduate degrees than anyone here and I am still disagreeing with the idea of CPVC for heat (approved or not), especially when someone can use O2 barrier PEX nowadays... just doesn't make sense to me!

Thanks for updating the page, Submanx1... makes for a great link for people to make an informed decision!

Have a good one guys!

[submanx1]

As I said before the O2 issue has put a different spin on the question.

I've been discussing this with Charlotte Pipe (Flow Gold) Here is a quote from them.

"CPVC CTS FlowGuard Gold does not typically require an oxygen barrier. In accordance with ASTM D 2846, CPVC CTS FlowGuard Gold is manufactured as a solid wall piping system and is not manufactured in a cross linked or co-extruded process like other materials that are prone to oxygen permeation. Unlike CPVC, some cross linked systems used in applications such as hydronic heating, require a layer of aluminum to be present to stop oxygen
diffusion through the polymer matrix."

I have been unable to get a CPVC O2 diffusion vs temp curve. Can any of you help? Flowgold provided some numbers for a specific temp but the units are in a form that is difficult to compare to the DIN standard.

[submanx1]

Yes I know that you think I am obsessed but this question has so many loose ends that need to be tied so --

I think that the Germans have approved CPVC for hydronic applications under DIN EN ISO 15877-1. However I do not seem to be able to to get a look at it without paying $150 or so. Any Ideas for getting a free copy of DIN EN ISO 15877-1?

[Mike45plus]

The community of professionals that frequent the " heatinghelp.com " website can help you answer your questions for free, and I think it will make for an interesting discussion.