97
RT-PRC010-EN
• VAV Supply Air Temperature control
with inlet guide vanes — Provided with
all the necessary controls to control/
operate a VAV rooftop from the
discharge air temperature, including a
discharge air microprocessor
controller, a discharge air sensor,
pressure sensor and inlet guide vanes.
The microprocessor controller
coordinates the economizer control
and the stages of cooling with zone or
outdoor air reset capabilities and an
adjustable control band to fine-tune the
control to specific applications. The
inlet guide vanes are used with VAV
rooftops to control duct static pressure.
Option includes vanes and static
pressure controls. Forward-curved fans
with inlet vanes are the most efficient
way to mechanically modulate airflow.
• Exhaust Fan Variable Frequency Drives
w/o Bypass (with Statitrac Only) —
Provided with all the necessary
controls to control/maintain building
space pressure through a CV or VAV
rooftop. The Variable Frequency Drive
(VFD) modulates the speed of the
exhaust fan motor in response to
building pressure. A differential
pressure control system, called
Statitrac, uses a differential pressure
transducer to compare indoor building
pressure to atmospheric pressure. The
VFD receives a 0-10vdc signal from the
unit microprocessor based upon the
space static pressure and causes the
drive to accelerate or decelerate as
required to maintain the space
pressure within the deadband.
• Exhaust Fan Variable Frequency Drives
and Bypass (with Statitrac Only) —
Bypass control provides full nominal
airflow in the event of drive failure.
• VAV Supply Air Temperature Control
with Variable Frequency Drives w/o
Bypass — Provided with all necessary
controls to operate a VAV rooftop from
the discharge air temperature,
including discharge air microprocessor
controller and discharge air sensor. The
microprocessor controller coordinates
the economizer control and the stages
of cooling with discharge air
temperature reset capabilities. Includes
factory installed and tested variable
frequency drives (VFD) to provide
supply fan motor speed modulation.
VFD receives 0-10vdc from the unit
microprocessor based upon supply
static pressure and causes the drive to
accelerate or decelerate as required to
maintain the supply static pressure
setpoint.
• VAV Supply Air Temperature Control
with Variable Frequency Drives and
Bypass — Bypass control provides full
nominal airflow in the event of drive
failure.
Ambient Control
• Low Ambient Dampers are provided
on condenser fan to allow the unit to
operate down to 0 F. (20-75 tons only)
Agency Approval
• Rooftops can be provided with either
Underwriter’s Laboratories (UL) or
Canadian Standards Association
(CSA) approval.
Miscellaneous Options
• Non-Fused Disconnect Switch with
External Handle — External handle
enables the operator to disconnect unit
power with the control box door closed
for safety.
• Hot Gas Bypass — Valves, piping and
controls are all included to allow
operation at low airflow, avoiding coil
frosting and damage to compressor.
When suction pressure falls below
valve adjustable setpoint, the valves
modulate hot gas to the inlet of the
evaporator.
• Economizer Control with Comparative
Enthalpy — used with the fresh air
economizer, two enthalpy sensors are
provided to compare total heat content
of the indoor air and outdoor air to
determine the most efficient air source
when economizing.
• Economizer Control with Reference
Enthalpy — used with the fresh air
economizer, an outdoor enthalpy
sensor is provided to compare the total
heat content of outdoor air to a locally
adjustable setpoint. The setpoint is
programmed at the human interface,
or remote human interface, to
determine if the outdoor enthalpy
condition is suitable for economizer
operation.
• Economizer Control with Dry Bulb —
used with the fresh air economizer, an
outdoor temperature sensor is
included for comparing the outdoor
dry bulb temperature to a locally
adjustable temperature setpoint. The
setpoint is programmed either at the
human interface, or remote human
interface, to determine if outdoor air
temperature is suitable for economizer
operation.
• Ultra Low Leak Fresh Air Dampers —
Dampers have chlorinated polyvinyl
chloride gasketing to seal to a leakage
rate of 1 percent of nominal airflow at
one-inch W.C. static pressure.
• High Duct Temperature Thermostats —
Two manual reset thermostats, one
located in the discharge section of the
unit set at 240 F and the other in the
return section set at 135 F. The
rooftop will shut down if the
thermostats are tripped.
• High Capacity Evaporator Coil —
Additional rows of coil and enhanced
evaporator tube surfaces provide
increased capacity compared to
standard coils.
• Copper Fins On Condenser Coil —
Copper fins offer extra corrosion
resistance as compared to standard
aluminum fins.
• Generic Building Automation System
(GBAS) Module — Provided for those
cases where the customer uses a
nonTracer building management
systems. The GBAS module provides a
binary input for Demand Limiting, four
(4) analog inputs for setpoint
adjustment and five (5) relay outputs
for diagnostic reporting. Inputs can use
a potentiometer or 0-5 vdc signal.
• High Efficiency Motors — Supply and
exhaust fans are provided with high
efficiency motors.
• Remote Human Interface Panel (RHI)
— Remote Human Interface Panel can
perform all the same functions as unit
mounted Human Interface Panel,
except for the Service Mode. Up to 4
rooftop units can be monitored and
controlled with a single Remote
Human Interface Panel. This panel uses
the same attractive enclosure as our
Tracker
®
building control panel. With
features such as a 2 line X 40 character
clear English display, a red LED light to
indicate an alarm condition (alarm also
shown on the two line display), a
simple 16 key keypad that is used in
conjunction with the display, to prompt
Options
