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SGH/SCH036, 060, 120, 240
Connect Gas Piping - SG Units
NOTE - Remove the cardboard shipping brace from the
flexible gas line in the power entry area before operating the
unit.
Before connecting piping, check with gas company or
authorities having jurisdiction for local code requirements.
When installing gas supply piping, length of run from gas
meter must be considered in determining pipe size for 0.5”
w.c. (.12kPa) maximum pressure drop. Do not use supply
pipe smaller than unit gas connection. For natural gas
units, operating pressure at the unit gas connection must
be a minimum of 4.5” w.c. (1.12kPa) and a maximum of
10.5” (2.60kPa) w.c. For LP/propane gas units, operating
pressure at the unit gas connection must be a minimum of
11” w.c. (2.74kPa) and a maximum of 13.0” w.c. (3.23kPa).
When making piping connections a drip leg should be
installed on vertical pipe runs to serve as a trap for
sediment or condensate. A 1/8” N.P.T. plugged tap is
located on gas valve for test gauge connection. See figure
30 for tap location. Install a ground joint union between
the gas control manifold and the main manual shut-off
valve. See figure 5 or 6 for gas supply piping entering
outside the unit. See figure 7 for gas supply piping
entering bottom the unit.
Compounds used on threaded joints of gas piping shall be
resistant to the action of liquified petroleum gases.
Pressure Test Gas Piping - SG 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 (3.48kPa).
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.
FIGURE 5
TO GAS
SUPPLY
MANUAL MAIN
SHUT-OFF VALVE
GROUND
JOINT UNION
COMPRESSOR AND
HEAT SECTION
BLOWER
SECTION
BOTTOM
POWER
ENTRY
TEE WITH
1/8' TAP
PRESSURE
REGULATOR
DRIP LEG
(REFER TO
LOCAL CODES)
TO GAS
VALVE
UNIT
PIPING
9” (229mm) MAXIMUM
DISTANCE PIPING
SHOULD EXTEND
FROM SIDE OF UNIT
9”
FIELD GAS
CONNECTION
SEAL
WEATHERTIGHT
SIDE ENTRY GAS PIPE CONNECTION
036, 060, 240 UNITS
FIGURE 6
SIDE ENTRY GAS PIPE CONNECTION - 120 UNITS
TO GAS
SUPPLY
MANUAL MAIN
SHUT-OFF VALVE
GROUND
JOINT UNION
BLOWER
SECTION
TEE WITH
1/8' TAP
PRESSURE
REGULATOR
DRIP LEG
(REFER TO
LOCAL CODES)
TO GAS
VALVE
UNIT
PIPING
9” (229mm) MAXIMUM
DISTANCE PIPING
SHOULD EXTEND
FROM SIDE OF UNIT
9”
FIELD GAS
CONNECTION
SEAL
WEATHERTIGHT
