Gas Piping; Pressure Test Gas Piping - Lennox LCH036 Installation Instructions Manual

joint union between the gas control manifold and the main
manual shut-off valve. See figure 4 for gas supply piping
entering outside the unit. Figure 5 shows complete
bottom gas entry piping.
Compounds used on threaded joints of gas piping shall be
resistant to the action of liquified petroleum gases.
OUTSIDE OF UNIT GAS PIPING
GROUND
JOINT UNION
MANUAL MAIN
SHUT-OFF VALVE
TO
GAS
SUPPLY
(REFER TO
LOCAL CODES)

GAS PIPING

SUPPORT
BOTTOM ENTRY GAS PIPING
TO GAS
VALVE
EXISTING
SUPPLY
FIGURE 5
TO GAS
VALVE
DRIP LEG
FIGURE 4
GROUND
JOINT UNION
MANUAL MAIN
SHUT-OFF VALVE
DRIP LEG
CAP
Pressure Test Gas Piping (Gas Units)
When pressure testing gas lines, the gas valve must
be disconnected and isolated. Gas valves can be
damaged if subjected to more than 0.5 psig (3.5kPa).
See figure 6.
NOTE-Codes may require that manual main shut-off
valve and union (furnished by installer) be installed in
gas line external to unit. Union must be of the ground
joint type.
After all connections have been made, check all piping
connections for gas leaks. Also check existing unit gas
connections up to the gas valve; loosening may occur
during installation. Use a leak detection solution or other
preferred means. Do not use matches candles or other
sources of ignition to check for gas leaks.
Some soaps used for leak detection are corrosive
to certain metals. Carefully rinse piping thoroughly
after leak test has been completed. Do not use
matches, candles, flame or othe sources of ignition
to check for gas leaks.
PRESSURE TEST GAS LINE
MANUAL MAIN
SHUT-OFF VALVE
GAS VALVE
Danger of explosion. Can cause injury
or product or property damage. Do not
use matches, candles, flame or other
sources of ignition to check for leaks.
NOTE-In case emergency shut down is required, turn off
the main manual shut-off valve and disconnect main
power to unit. These devices should be properly labeled
by the installer.
Page 6
CAUTION
CAP
FIGURE 6
WARNING