9
Refer to the Roof Curb Installation Instructions for proper
curb installation. Curbing must be installed in compliance
with the National Roofing Contractors Association Manual.
Lower unit carefully onto roof mounting curb. While rigging
unit, center of gravity will cause condenser end to be lower
than supply air end.
Unit should be lifted by the
4 holes
located at the
base
frame corners.
Lifting cables should be attached to the
unit with shackles. While rigging unit, center of gravity will
cause the condenser end (heavier) to be lower than supply
air end. The distance between the unit and the crane hook
up should not be
less
than
60”
. The spreaders bars should
span over the unit to prevent damage to the cabinet from
the lifting cables.
Rigging
GAS PIPING
IMPORTANT NOTE: This unit is factory set to
operate on natural gas at the altitudes shown on
the rating plate.
The rating plate is stamped with the model number, type of
gas and gas input rating. Make sure the unit is equipped to
operate on the type of gas available.
Natural
Min. 5.0" W.C., Max. 10.0" W.C.
INLET GAS PRESSURE
Inlet Gas Pressure Must be within the Minimum and the
Maximum Value Shown in the Inlet Gas Pressure Table.
The minimum supply pressure should not vary from that
shown in the table because this could prevent the unit
from having dependable ignition. In addition, gas input to
the burners must not exceed the rated input shown on the
rating plate. Overfiring of the unit could result in premature
heat exchanger failure.
CAUTION
To prevent unreliable operation or equipment damage, the
inlet gas supply pressure must be as specified on the unit
rating plate with all other household gas fired appliances
operating.
Piping
WARNING
To avoid possible unsatisfactory operation or equipment
damage due to underfiring of equipment, use the proper size
of natural gas piping needed when running pipe from the
meter to the furnace.
The rating plate is stamped with the model number, type of
gas and gas input rating. Make sure the unit is equipped
to operate on the type of gas available. The gas line
installation must comply with local codes, or in the absence
of local codes, with the latest edition of the National Fuel
Gas Code NFPA 54/ANSI Z223.1.
Natural Gas Connection
1/2
3/4
1
1 1/4 1 1 /2
10
132
278
520
1050
1600
20
92
190
350
730
1100
30
73
152
285
590
980
40
63
130
245
500
760
50
56
115
215
440
670
60
50
105
195
400
610
70
46
96
180
370
560
80
43
90
170
350
530
90
40
84
160
320
490
100
38
79
150
305
460
Pressure= .50 PSIG or less and Pressure Drop of 0.3" W.C.
(Based on 0.60 Specific Gravity Gas)
Natural Gas Capacity of Pipe
in Cubic Feet of Gas Per Hour (CFH)
Nominal Black Pipe Size (inches)
Length of
Pipe in Feet
Heating Value of Gas (BTU/Cubic Foot
CFH =
BTUH Furnace Input
1. Refer to the Proper Piping Practice drawing for the
general layout at the unit. The following rules apply:
2.
Use black iron pipe and fittings for the supply piping.
The use of a flex connector and/or copper piping is
permitted as long as it is in agreement with local codes.
3. Use pipe joint compound on male threads only. Pipe
joint compound must be resistant to the action of the
fuel used.
4. Use ground joint unions.
5. Install a drip leg to trap dirt and moisture before it can
enter the gas valve. The drip leg must be a minimum
of three inches long.
6. Use two pipe wrenches when making connection to
the gas valve to keep it from turning.
7.
Install a manual shut-off valve in a convenient location
(within six feet of unit) between the meter and the unit.
8. Tighten all joints securely.
9. The unit must be connected to the building piping by
one of the following methods:
