Installation Guide

35
Underground Installations
Performance Testing
A performance test of the regulator should be conducted to conrm that adequate pres-
sure reaches all appliances. During the test, all appliances should be running at full load to
make sure that adequate pressure is maintained under full-load conditions for the gas piping
system. The inlet pressure for gas appliances should be equal to, but not greater than, the
appliance's recommended inlet pressure range. If the pressure is not within this range, adjust-
ments to the service regulator or the pounds-to-inches gas line regulator may be required to
adjust line pressure.
Regulator Adjustments
Regulators can be adjusted to deliver dierent
outlet pressures downstream of the regulator.
To adjust a regulator, remove the seal cap to
expose the adjusting screw. Turn the screw
clockwise to increase outlet pressure, or
counter-clockwise to decrease pressure. (Fig-
ure 4.25)
If the spring adjustment doesn’t result in the
desired pressure, make sure the supply pressure is at least equal to the desired outlet pressure
plus the pressure drop of the regulator. If this pressure is adequate, contact to the manufac-
turer. DO NOT continue to turn the screw clockwise if the outlet pressure reading doesn’t
increase as this may result in over-ring should there be an increase in inlet pressure.
4.9 Underground Installations
Building codes require that gas piping runs that come in contact with earth or other material
that could corrode the piping be protected from corrosion. Piping installed beneath (under-
ground) or within the slab of a building must be encased in a nonmetallic water-tight conduit
that is vented. Fittings and couplings are not permitted when HOME-FLEX® is installed under-
ground.
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
conduit 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 ter-
mination 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 4.26, Figure 4.27, and "" on
page 36). 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.
Figure 4.25 Pressure Regulator Diagram
Gas
Flow
Spring
Cover
Closing Nut
Adjusting Screw
Vent Limiter
Diaphragm
Appliance
Pressure
Body
Balancing
Seat
Gas Pressure Pushes up
Pushes downSpring
Figure 4.26 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 4.27 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