RIGGING DETAILS
IMPORTANT NOTE: If using bottom discharge with roof curb, ductwork should be attached to the curb prior to installing the unit. Ductwork dimensions are shown in roof curb installation instructions.
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.
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. Conversion to LP gas is permitted with the use of the factory authorized conversion kit
| INLET GAS PRESSURE | |
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Natural |
| Min. 5.0" W.C., Max. 10.0" W.C. |
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Propane |
| Min. 11.0" W.C., Max. 13.0" W.C. |
Inlet Gas Pressure Must Not Exceed the Maximum Value Shown in Table Above.
The minimum supply pressure should not vary from that shown in the table above 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.
HIGH ALTITUDE DERATE (U.S. INSTALLATIONS ONLY)
IMPORTANT NOTE: The gas/electric units naturally derate with altitude. Do not attempt to increase the firing rate by changing orifices or increasing the manifold pressure. This can cause poor combustion and equipment failure. At all altitudes, the manifold pressure must be within 0.3 inches W.C. of that listed on the nameplate for the fuel used. At all altitudes and with either fuel, the air temperature rise must be within the range listed on the unit nameplate.
Refer to the Installation Manual provided with the LP kit for conversion from natural gas to propane gas and for altitude adjustments.
Use HA02 for installations above 2000’.
PIPING
IMPORTANT NOTE: To avoid possible unsatisfactory operation or equipment damage due to under firing of equipment, do not undersize the natural/propane gas piping from the meter/ tank to the unit. When sizing a trunk line, include all appliances on that line that could be operated simultaneously.
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
Natural Gas Capacity of Pipe
in Cubic Feet of Gas Per Hour (CFH)
Length of |
| Nominal Black Pipe Size (inches) |
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Pipe in Feet | 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)
CFH = | BTUH Furnace Input | |
Heating Value of Gas (BTU/Cubic Foot) | ||
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Refer to the Proper Piping Practice drawing for the general layout at the unit. The following rules apply:
1.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.
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
7.Tighten all joints securely.
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