York PREDATOR MagnaDRY DR090, Technical Manual

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Subject to change without notice. Printed in U.S.A. 246721-YTG-C-0606
Copyright © 2006 by Unitary Products Group . All rights reserved. Supersedes: 246721-YTG-B-0305/036-21551-001-B-0305
Unitary 5005 Norman
Products York OK
Group Drive 73069
outdoor and return air damper assembly to prevent the
supply air temperature from dropping below 55 ºF.
Changeover from compressor to economizer operation
shall be provided by an integral electronic enthalpy con-
trol that feeds input into the basic module. The outdoor
intake opening shall be covered with a rain hood that
matches the exterior of the unit. Water eliminator/filters
shall be provided. Simultaneous economizer/compressor
operation is also possible. Dampers shall fully close on
power loss. Available with barometric relief or power
exhaust.
2. MOTORIZED OUTDOOR AIR DAMPERS – Outdoor
and return air dampers that are interlocked and posi-
tioned by a 2-position, spring-return damper actuator.
The maximum leakage rate for the outdoor air intake
dampers shall not exceed 2% when dampers are fully
closed and operating against a pressure differential of
0.5 IWG. A unit-mounted potentiometer shall be provided
to adjust the outdoor and return air damper assembly to
take in the design CFM of outdoor air to meet the ventila-
tion requirements of the conditioned space during normal
operation. Whenever the indoor fan motor is energized,
the dampers open up to one of two pre-selected posi-
tions – regardless of the outdoor air enthalpy. Dampers
return to the fully closed position when the indoor fan
motor is de-energized. Dampers shall fully close on
power loss.
ADDITIONAL FACTORY INSTALLED OPTIONS
• ALTERNATE INDOOR BLOWER MOTOR – For appli-
cations with high restrictions, units are available with
optional indoor blower motors that provide higher static
output and/or higher airflow.
• CONVENIENCE OUTLET (POWERED/NON-POW-
ERED)
– Unit can be provided with an optional 120VAC
GFCI outlet with cover on the corner of the unit housing
the compressors.
• ELECTRIC HEAT - Electric Heaters range from 9 kW to
54 kW and are available in all the voltage options of the
base unit.
• PHASE MONITOR - Designed to prevent damage in out-
of-phase condition.
• COIL GUARD - Designed to prevent condenser coil
damage.
• BAS CONTROLS - Include supply air sensor, return air
sensor, dirty filter indicator and air proving switch.
• DIRTY FILTER SWITCH – This kit includes a differential
pressure switch that energizes the fault light on the unit
thermostat, indicating that there is an abnormally high-
pressure drop across the filters.
• BREAKER – An HACR breaker can be factory installed
on gas heat units or cooling units with electric heat.
• DISCONNECT SWITCH - A disconnect can be factory
installed on a cooling only units sized for the largest elec-
tric heat available.
• STAINLESS STEEL HEAT EXCHANGER – For applica-
tions in a corrosive environment, this option provides a
full stainless steel heat exchanger assembly.
• STAINLESS STEEL DRAIN PAN - Provides years of
trouble free operation in corrosive environments.
• SMOKE DETECTOR – A smoke detector can be factory
mounted and wired in the supply and/or return air com-
partments.
OTHER PRE-ENGINEERED ACCESSORIES AVAILABLE
• ROOF CURB - 14” and 8” high, full perimeter knockdown
curb, with hinged design for quick assembly.
• BAROMETRIC RELIEF DAMPER – (Unit mounted –
Downflow, Duct Mounted – Horizontal) – Contains a rain
hood, air inlet screen, exhaust damper and mounting
hardware. Used to relieve internal air pressure through
the unit during economizer operation.
• PROPANE CONVERSION KIT – Contains new orifices
and gas valve springs to convert from natural to L.P. gas.
• 60 ºF GAS HEAT KIT – Provides an electric heat kit for
the gas compartment for use in extreme low ambient
conditions.
• ECONOMIZER (Downflow and Horizontal flow)
• POWER EXHAUST – (Unit mount – Downflow, Duct
mount – Horizontal flow)
• DUAL ENTHALPY KIT - Provides a second input to
economizer to monitor return air.