PRODUCT DESIGN
18
WARNING
TO AVOID THE RISK OF PROPERTY DAMAGE,
PERSONAL INJURY OR FIRE, USE ONLY COPPER
CONDUCTORS.
If it is necessary for the installer to supply additional line
voltage wiring to the inside of the package unit, the wiring
must comply with all local codes. This wiring must have a
minimum temperature rating of 105°C. and must be routed
away from the burner compartment. All line voltage splices
must be made inside the unit control box.
GAS SUPPLY AND PIPING
CAUTION
THIS PACKAGE GAS UNIT IS FACTORY SET TO
OPERATE ON NATURAL GAS AT THE ALTITUDES
SHOWN ON THE RATING PLATE. IF OPERATION
ON PROPANE IS REQUIRED, OBTAIN AND INSTALL
THE PROPER CONVERSION KIT(S) BEFORE
OPERATING THIS UNIT. FAILURE TO DO SO
MAY RESULT IN UNSATISFACTORY OPERATION
AND/OR EQUIPMENT DAMAGE.
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.
Inlet Gas Pressure
Natural
Min. 5.0" W.C., Max. 10.0" W.C.
Propane
Min. 11.0" W.C., Max. 13.0" W.C.
Inlet Gas Pressure Must Not Exceed the Maximum Value
Shown in the table above.
The minimum supply pressure must not be varied downward
because this could lead to unreliable 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.
GAS PIPING
CAUTION
TO AVOID POSSIBLE UNSATISFACTORY OPERATION
OR EQUIPMENT DAMAGE DUE TO UNDERFIRING OF
EQUIPMENT, DO NOT UNDERSIZE THE NATURAL
GAS/PROPANE PIPING FROM THE METER/TANK TO
THE FURNACE. WHEN SIZING A TRUNK LINE PER
THE TABLES, INCLUDE ALL APPLIANCES ON THAT
LINE THAT COULD BE OPERATED SIMULTANEOUSLY.
The gas pipe supplying the unit must be properly sized based
on the cubic feet per hour of gas flow required, specific gravity
of the gas and length of the run. 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 ANSI
Z223.1.
NATURAL GAS CAPACITY OF PIPE IN CUBIC FEET OF
GAS PER HOUR (CFH)
LENGTH OF
PIPE IN FEET
NOMINAL BLACK PIPE SIZE
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
BTUH FURNACE INPUT
CALORIFIC VALUE OF GAS
CFH =
CONNECTING THE GAS PIPING - NATURAL GAS
1. Use black iron or steel pipe and fittings for the building
piping.
2. Use pipe joint compound on male threads only. Pipe joint
compound must be resistant to the action of the fuel used.
3. Use ground joint unions.
4. 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.
5. Use two pipe wrenches when making connection to the
gas valve to keep it from turning.
6. Install a manual shut off valve. This shut off valve should
be conveniently located within six (6) feet of the unit, and
between the meter and unit.
7. Tighten all joints securely.
8. Connect the unit to the building piping by one of the
following methods.
a.
Rigid metallic pipe and fittings.
b.
Semi-rigid metallic tubing and metallic fittings.
Aluminum alloy tubing shall not be used in exterior
locations.
c.
Listed gas appliance connectors used in accor-
dance with the terms of their listing that are
completely in the same room as the equipment.
