
Parker Hannifin Corporation
Parflex Division
Ravenna, Ohio
Bulletin No. 4660-PGP2T
Parflex
®
Flexible Gas Piping System
Design and Installation Guide
2.1 Parflex System Description
The Parflex Flexible Gas Piping System, Parflex System, has a number of essential hardware and design differences
from conventional gas piping systems using rigid steel (Schedule 40) pipe. These differences can be described as
follows:
a) The system uses CSST made of 300 series type material.
b) The CSST is connected using special patented FastMate™ quick connect mechanical fittings designed specifi-
cally for Parker Parflex CSST.
c) In many applications, the CSST is sized for individual gas appliance loads and is, therefore, usually small in
diameter. CSST can be piped in parallel from a distribution manifold and in series like common steel pipe sys-
tems.
d) The small diameter CSST is suitable for use with elevated pressure systems (above 1/2 psi up to 5 psi).
e) Different practices are required in the handling and installation of semi-rigid tubing compared to steel pipe.
The Parflex System may be Applied in combination with schedule 40 steel pipe using approved threaded couplings
at the interface.
CSST can be used for both the low-pressure system (below 1/2 psi) and elevated-pressure system
design. It is approved for propane and natural gas applications.
The final Application depends on local plumbing restrictions and codes, floor plan, appliance locations, availability
of elevated street pressure and total gas load. This design manual does not dictate the type of the gas distribution
system configuration. The configuration is left up to the system designer. This manual will aid in sizing tubing for the
system once the configuration has been selected. The installer should contact the local gas distributor to confirm
available service pressures.
Section 2.0 System Components