How to Guide

108
Plastics Technical Manual
2. Short-term elevated pressure performance
 CPVCmeetsthequalitycontrolprovisionsoftheASTM
D 2846 Standard (Table 5) which requires that CPVC-
CTS systems (pipe, fittings, and cemented joints) have
the capability of withstanding short-term pressure tests
at 180°F of at least 521 psi for 6 minutes and 364 psi
for 4 hours.
Flanges and Unions
Please see the section of this technical manual for complete
informationonFlangesandUnions.
Horizontal and Vertical
Support
Mostplumbingandbuildingcodesrequiresupportforhori-
zontalpipelinesevery3feetforpipein
1
⁄2”-1”diameters,and
every4feetforpipewithdiametersgreaterthan1”.Support
spacing should be in accordance with applicable plumbing
and building codes.
Vertical CPVC piping should be properly supported and have
a mid-story guide, unless thermal expansion requires another
design.
The pipe should not be anchored tightly by the support, but
secured in a manner to allow for movement caused by thermal
expansion and contraction. It is recommended that you use
clamps or straps that allow pipe to remain away from the
framing, thus reducing the noise generated when pipe is al-
lowedtorubagainstwood.Usehangersandclampsthatare
chemically compatible with CPVC.
HVAC Condensate Drain Lines
Exercise caution when using FlowGuard Gold
®
CPVC pipe or
ttingsforHVAC-orrefrigerant-condensatelines.Somere-
frigerant systems contain oils that may damage CPVC products.
In HVAC applications, some heat exchangers or condenser
coils may contain residual oils from the manufacturing process
which can cause cracking of CPVC. Caution should be exercised
wheninstallingCPVCincombinationhot/airhandlingunits
or as condensate-drain lines from air conditioning systems.
Confirm the compatibility of CPVC with residual oils prior to
installation. The interior of heat exchangers or the exterior of
condenser coils may be thoroughly cleaned with a detergent
solution to remove incompatible oils prior to piping installa-
tion. A rinse with clean water to completely clean the system is
advisable as a final flushing. Charlotte Pipe and Foundry will
not accept responsibility for failure resulting from exposure
tocompressoroilsinHVAC-orrefrigerant-condensatelines.
Low Temperature
Recommendation
Like most materials, PVC and CPVC become more brittle at
lowtemperatures,particularlyattemperaturesbelowfreezing
(32°F). Charlotte Pipe and Foundry recommends taking proper
precautions when installing systems at low temperatures
including providing proper insulation. If a system is designed
tooperateattemperaturesbelowfreezing(32ºF),Charlotte
Pipe recommends the following:
1. Reduce water hammer pressure surges to a minimum
by:
 a. Usingonlyslow-actingsolenoidvalves,ifany.
b. Reducing pump start-up pressure surges with slow
start-up motors and rubber expansion devices.
 c. Notexceedingmaximumuidvelocityof5-feetper
second for PVC and 8-feet per second for CPVC CTS.
2. Provide more than minimum Charlotte Pipe recommended
support spacing.
3. Thrust blocking at branches, changes in direction and end
of runs.
4. Use expansion/contraction devices when temperature
changes occur in runs.
5. Strictly follow chemical-resistance recommendations.
6. ProtectpipingfromUV,ifapplicable.
SPECIAL CONSIDERATIONS
Prior to installing PVC or CPVC piping in hydronic
applications, it is important to flush the interior of the heat
exchangers and the exterior of the condenser coils
thoroughly with a mild ionic detergent solution to remove
incompatible oils. Failing to do so could result in system
failure and property damage.
Verify that all boiler cleaning and sealing chemicals used in
hydronic radiant heating systems are compatible with PVC
or CPVC. Failure to do so could result in system failure and
property damage.
Equipment leaks in refrigeration or HVAC systems may
release POE oils or other contaminants into the piping
system. These oils and contaminants are incompatible with
PVC or CPVC and such exposure may result in pipe or
fitting failure regardless of flushing.