How to Guide

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SUPPLEMENTAL INFORMATION
Combustion Gas Venting
Failure to properly vent combustion gas may result in
serious injury or death from carbon monoxide.
• Always install / use pipe or fittings as specified by the
appliance manufacturer's installation instructions to
vent appliances.
• Never use PVC cellular core, ABS cellular core pipe or
ConnecTite
®
fittings for combustion gas venting.
It is important to note that the chemical properties of all
thermoplastic materials change over time. Visually, this of-
ten means that the pipe may experience color variations. In
CTS CPVC applications the temperature of the water run-
ning through the pipe often determines the degree of varia-
tion, with hot water causing a more noticeable change. Ex-
posure to ultraviolet (UV) light may also cause the exposed
surface of PVC or CPVC to brown. Purple PVC, purple
CPVC or ABS pipe tend to fade with UV exposure (please
see Weathering / UV Exposure for additional information).
Color variations do not indicate that the pressure carrying
capabilities of the pipe have been compromised. In fact, the
pressure carrying capability of thermoplastic pipe increases
as the pipe ages.
What also changes over time is the impact resistance of ABS,
PVC and CPVC piping systems, which has little effect upon
installed systems. It does mean, however, that if a cut-in is
necessary, additional care should be taken to prevent dam-
aging the existing system. This is typically a greater issue
with thin-wall, smaller-diameter piping systems such as CTS
CPVC, PVC PR 200, PVC PR 160 or Schedule 40 PVC.
Ratchet cutters may compress the pipe and cause end cracks
on aged pipe. Even if the cracks are not visible, they can
eventually propagate through the fitting and cause a leak.
Charlotte Pipe recommends using a fine-tooth saw when per-
forming cut-in operations. Once the pipe is cut, continue with
standard installation procedures. Keep in mind that if the
area is wet, additional cure time is required and may be three
times as long. The inside and outside diameter of pipe and
fittings should be kept as dry as possible.
Repairs or Modifications to Existing ABS, PVC or CPVC Systems
Using Plastics in Multi-Story
Construction
Incorporating plastic piping systems into multi-story con-
struction raises special design considerations. Charlotte Pipe
plastic pipe and fittings are warranted to conform to ASTM
or other applicable product-based standard, not for any par-
ticular system design.
Products and materials selected for use in multi-story con-
struction (four floors and up) must conform to all applicable
building, plumbing and fire codes. Product selection and/
or specification should be made by an architect, engineer,
contractor, or other licensed professional. This must include
specification of a code-compliant, chemically compatible
firestop system with an appropriate service life, which must
be properly installed and inspected for conformance to build-
ing, plumbing and fire codes by the responsible governmental
authority.
In selecting products and material for multi-story construc-
tion, consideration should be given to Charlotte Pipe’s cast
iron soil pipe products, which are an excellent choice for
many multi-story applications. Charlotte Pipe recommends
noncombustible cast iron DWV piping systems in multi-story
construction.
Using Plastics for Combustion Gas Venting
Charlotte Pipe recommends that inquiries about the suit-
ability of plastic piping systems for venting combustion
gases should be directed to the manufacturer of the water
or space heating equipment being installed. As stated in the
International Code Council’s International Fuel Gas Code
503.4.1.1:
Plastic Pipe and ttings used to vent appliances shall be
installed in accordance with the appliance manufacturer’s
installation instructions.
The residential water heater certification and safety stan-
dard, ANSI Z21.10 1-2014/CSA 4.1-2014, has been modi-
fied as it relates to the use of certain plastic venting materi-
als and now prohibits the use of cellular core pipe. Charlotte
Pipe prohibits the use of its PVC and ABS cellular core pipe
for all combustion gas venting applications.
Furthermore, several of the ASTM standards applicable to
plastic pipe and fittings that Charlotte Pipe manufactures
include the following note: This standard specification does
not include requirements for pipe and fittings intended
to be used to vent combustion gases.