PAGE 50 of 84 HU-SOUTHWEST-1480 GAS-FIRED HUMIDAIRE UNIT
© SAMUEL JACKSON, INCORPORATED 2005 ALL RIGHTS RESERVED
Joints should be taped to prevent air leakage before draw bands are applied to joints. The
pipe which conducts the humid air to the point of application is often insulated (lagged)
to prevent condensation. If the insulation has an outer covering which is impervious,
then it should not be applied to the pipe joints. Otherwise, slight leaks of vapor through
the pipe joints will fill the insulation with water vapor which will cause condensation.
Interrupting the insulation at the pipe joints allows this vapor to escape.
ELECTRICAL:
Electrical connections and troubleshooting are covered in the electrical
section of this manual. The electrical supply required for the Humidaire Unit is 3 phase
480VAC, 60 HZ (15 Amperes) in the US and 380VAC, 50 HZ or 415VAC, 50 HZ (18
Amperes) in most other countries.
FUEL GAS:
Connect the pipe supplying natural gas or LPG to the gas cock on the gas
regulator assembly. The pipe used should be free of sand, metal chips, and other debris.
Even if it is free of debris, use the gas to flush the pipe by removing the pipe cap at the
bottom of the gas regulator assembly and opening the gas cock until clean gas comes out.
DO NOT take gas supply from downstream side of low-pressure regulator serving
another burner. Go ahead of such regulators to get a pressure of 5 to 20 PSI (0.3 to 1.4
bars). The regulator installed in the Humidaire Unit will lower this to the proper level (to
be adjusted by serviceman at startup). Ordinarily, 1-inch pipe will be adequate, but if
more than one Humidaire Unit is served or long distances are involved, refer to the Table
of
RECOMMENDED MINIMUM PIPE SIZES
included in this manual.
The burner capacity of the Humidaire Unit is 2-million BTU/Hr (500,000 Kg-Cal/Hr),
but it can be increased to 3-million BTU/Hr simply by changing the orifice disk in the
burner head. The required burner capacity is determined by the quantity of air flowing
through the unit. Full-throttle fuel consumption at 3-million BTU/Hr is as follows:
Natural gas -- 3,000 cubic ft/hour (85 cubic meters/hr); Propane -- 35 gal/hr (132 liters/hr
or 75 Kg/hr).
For LPG (propane or butane) installation, some gins use a large storage tank without a
vaporizer. In such cases, make sure that your gas man installs a 15-pound regulator at the
tank. DO NOT run the high pressure gas underground ahead of the regulator. To do so
will cause condensation of liquid LPG in your gas line. This will damage the Humidaire
Unit and other burners, and will create a dangerous condition. If the gas line in your
building feels extremely cold during operation, you have liquid in your line, and you
should correct the situation immediately. For more information, refer to the Drawing
LIQUEFIED PETROLEUM GAS TANK INSTALLATION FOR HUMIDAIRE UNITS
AND DRYING HEATERS
included in this manual.
Some local authorities may require piping the screened vent opening of the gas regulator
to the outside of the building.
