FIELD--INSTALLED ACCESSORIES
SINGLE INPUT ELECTRONIC ENTHALPY ECONOMIZER --
Includes a slide--in/plug--in damper assembly with fully
modulating spring return motor actuator capable of introducing
up to 100% outdoor air, one outdoor air electronic enthalpy
sensor and a rainhood with filters. The rainhood is painted to
match the basic unit and must be field--assembled before
installation. Economizer dampers are 2% low leakage type.
DUAL INPUT ELECTRONIC ENTHALPY ECONOMIZER --
Includes the same damper system and rainhood with filters as
described for a single enthalpy economizer above except this
accessory contains two enthalpy sensors. It uses a differential
enthalpy control that compares the outdoor air versus the
return air. The logic module then optimizes the economizer
operation for additional savings over the single input
economizer.
MOTORIZED AIR DAMPER -- Includes a slid--in/plug--in
damper assembly with a rainhood and filters. The outdoor air
dampers open when the indoor fan motor is energized. The
damper is capable of providing 0% through 100% of outdoor
return air opening.
MANUAL OUTDOOR DAMPER -- Provides 0% through 35%
or 0% through 100% of return air opening (field adjustable).
Designed for duct mounted side or bottom supply/return
applications. Includes rain hood assembly and filter.
ELECTRIC HEATERS -- Include nickel chromium elements, a
terminal block, fuses (where required by UL), all the necessary
connectors and hardware. All heaters utilize single point power
supply hookup. Capacities from 5 KW thru 30 KW heating are
available.
FUSE BLOCK KITS -- These kits have a fuse box with a fuse
block and fuses. They're available for all 460--3--60 volt
heaters and 208/230--3--60 volt heaters 7 KW and smaller.
ROOF CURB -- This 14" high full perimeter roof curb is
knocked down for field assembly and contains duct supports
that can easily be shifted for the desired unit duct arrangement.
No deck is required because the unit underside is insulated.
START ASSIST KIT (Standard on 4 ton units) -- Provides
increased starting torque for 3 and 5 ton single phase units in
areas with low voltage conditions. It contains a 12.5 OHM
PTCR temperature resistor with a support clip and hardware
for mounting.
ANTI--RECYCLE TIMER -- A timer to prevent the unit
compressor from short cycling. It assures 5 minutes off time
between compressor cycles.
OUTDOOR COIL GUARD -- Consists of grille--type sections
for assembling over the outdoor coil to protect it from damage.
WALL THERMOSTAT -- The units are designed to operate
with 24--volt electronic and electro--mechanical thermostats.
All units can operate with single stage heat/single stage cool
thermostats -- with or without the economizer. To obtain
maximum economizer operating savings, a two stage cooling
thermostat should be used. To obtain two stage cooling
operation, a jumper wire must be removed on the low voltage
relay board. (See unit wiring diagram.)
OUTDOOR THERMOSTAT -- A 24--volt thermostat providing
two stages of control for units equipped with supplemental
electric heaters.
036-21564-002-A-0404
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Unitary Products Group
FACTORY INSTALLED OPTIONS
ECONOMIZERS - Units equipped with the factory-installed
economizer option have dampers that are positioned by a
spring return, fully modulating damper actuator capable of
introducing up to 100% outdoor air. As the outdoor air intake
dampers open, the return air dampers close. The changeover
from mechanical refrigeration to economizer operation is
determined by a single input electronic enthalpy control or by a
dual input electronic enthalpy control. Simultaneous
compressor and economizer operation is also possible.
The single enthalpy system contains a sensor that monitors the
outdoor air which automatically operates the damper actuator
allowing the dampers to open or close.
The dual enthalpy system contains a second sensor that
monitors the return air in addition to monitoring the outdoor air
described above for a single enthalpy system. The logic module
compares these two values and modulates the dampers
providing the maximum efficiency of the economizer system.
The economizer is completely installed and wired at the factory.
Only the outdoor air hood, including its filters, need be
assembled and installed in the field.
BELT-DRIVE BLOWERS - Adjustable belt-drive blowers,
providing maximum flexibility to handle many airflow
requirements, are available on all models.
