Installation Guide

HOME-FLEX CSST 37
Electrical Bonding
HOME-FLEX® should never be buried directly underground without a conduit. To route
HOME-FLEX® tubing underground, it must be protected within a nonmetallic water-tight
conduit that is at least ½" larger than the outer diameter of the CSST tubing. Fittings and
joints are not permissible in such runs; the run must be one unbroken line of tubing.
For outdoor underground installations, the annular space between the CSST and the nonme-
tallic conduit must be sealed to prevent entrance of moisture, dirt, debris, and insets.
For indoor buried installations, the annular space between the CSST and the nonmetallic con-
duit does not have to be sealed. In the event that local code requires the conduit to be vented,
the use of a tee designed for use with nonmetallic conduit may be placed at the termination
end of the conduit. One end of the tee should be sealed while the other outlet can be used to
connect a vent line that is routed outside (See Figure 4.28, Figure 4.29, and Figure 4.27). Vent
lines routed to the outside of a structure must be installed in such a manner to prevent
entrance of moisture, dirt, debris, and insects.
Note: If installed underneath mobile homes or in
crawl spaces, HOME-FLEX® should be installed in
accordance with Section 4.3, Outdoor Installa-
tion Issues.
4.10 Electrical Bonding
Proper bonding and grounding may reduce the risk of damage and re from electrical arcing
to CSST as a result of a lightning strike. Lightning does not have to strike a structure directly
to cause damage. Conductive systems, like piping or wiring, can become energized indirectly
by a lightning strike. When systems are not properly bonded, the current from the energized
line can cause electricity to arc (or jump) from one system to another and damage the CSST.
Proper adherence to the bonding instructions should lower the risk of electrical arcing and
related damages.
Table 4.7 Burial Depths for Underground Routing
Outdoors Minimum of 12”
In slab
1-½” minimum concrete
coverage
Under slab
No minimum burial depth
below slab, or in compliance
with local codes
Table 4.8 Conduit Termination Height for Under-
ground Routing
Indoors
Conduit to extend a minimum
of 1” above nished oor
height
Outdoors
Conduit to extend a minimum
of 4” above nished grade
Ends of conduit to be
sealed
Vent
Figure 4.27 Installation in Nonmetallic Conduit with Venting
Figure 4.28 Installation in Nonmetallic Conduit Under Slab
Ends of conduit do not have
to be sealed
4" Min
PVC or PE Conduit*
No minimum burial depth beneath slab except
as specied by local code
Recommended minimum bend radius: 6"
*ID of conduit should be at least 1/2" greater than OD of CSST
Figure 4.29 Installation in Nonmetallic Conduit In Slab
Ends of conduit do not have
to be sealed
CSST
4" Min
PVC or PE Conduit*
1
1
⁄2" minimum concrete cover
1
1
⁄2" Min
Footing
Recommended minimum bend radius: 6”
*ID of conduit should be at least 1/2” greater than OD of CSST