York DH 036 Technical Manual page 14

• ROOF CURBS - Eight and fourteen-inch high roof curbs
provide a water-tight seal between the unit and the fin-
ished roof. These full perimeter curbs meet the require-
ments of the National Roofing Contractors Association
(NRCA) and are shipped knocked-down for field assem-
bly.
Roof curbs are designed to fit inside the base rails of the
unit and include both a wood nailing strip and duct
hanger supports.
• HIGH ALTITUDE NATURAL GAS - Burner orifices and
pilot orifices are provided for proper furnace operation at
altitudes up to 6,000 feet.
• PROPANE - Burner orifices, pilot orifices and gas valve
parts are provided to convert a natural gas furnace to
propane.
• HIGH ALTITUDE PROPANE - Burner orifices and pilot
orifices are provided for proper furnace operation at alti-
tudes up to 6,000 feet. This accessory supplements the
basic propane conversion kit.
• LOW NOX KIT - Required to reduce the emission of
nitrogen oxides below 40 nano grams per joule.
• POWER EXHAUST - Our single input economizer
options are available with power exhaust. Whenever the
outdoor air intake dampers are opened for free cooling,
the exhaust fan will be energized to prevent the condi-
tioned space from being over-pressurized during econo-
mizer operation.
The power exhaust option can only be used on bot-
tom duct configurations.
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• BAROMETRIC RELIEF DAMPER - This damper acces-
sory can be used to relieve internal building air pressure
on units with an economizer without power exhaust. This
accessory includes a rain hood, a bird screen and a fully
assembled damper. With bottom duct connections, the
damper should be mounted over the opening in the
return air panel. With horizontal ductwork, the accessory
should be mounted on the return air duct.
• ENTHALPY ACCESSORY CONTROL KIT - This kit
contains the required components to convert a single
enthalpy economizer to dual enthalpy.
• BURGLAR BARS - Mount in the supply and return
openings to prevent entry into the duct work.
• FLUE EXHAUST EXTENSION KIT - In locations with
wind or weather conditions which may interfere with
proper exhausting of furnace combustion products, this
kit can be installed to prevent the flue exhaust from
entering nearby fresh air intakes.
• CO SENSOR - Senses CO
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overrides the economizer when levels rise above the
present limits.
• COIL GUARD - Customers can purchase a coil guard kit
to protect the condenser coil from damage. This is not a
hail guard kit.
• HAIL GUARD - Hail Guard kit is available to prevent unit
from hail damage. This is a sloped hood that fits above
the coil.
• GAS PIPING KIT - This kit supplies all necessary fittings
and shut off valve.
036-21506-003-C-0405
levels and automatically
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Unitary Products Group