12
Economizer
Economizers save energy, money and improve comfort levels
in the conditioned space. They bring in fresh, outside air for
ventilation; and provide cool outside air to cool your building.
This is also the preferred method of low ambient cooling.
When integrated with CO
2
sensors, economizers can provide
even more savings by coupling the ventilation air to only the
amount required based on space occupancy. Economizers are
available, installed and tested by the factory, with either
enthalpy or temperature dry-bulb inputs. There are also models
for electromechanical and direct digital controllers. Additional
sensors are available as accessories to optimize the economizer.
Economizers include gravity controlled barometric relief that
helps equalize building pressure and ambient air pressures.
This can be a cost effective solution to prevent building pres-
surization. Economizers are available in Ultra Low Leak and
standard low leak versions.
CO
2
sensor
CO
2
sensors improve productivity and save money by working
with the economizer to intake the correct amount of outside air
for ventilation. As occupants fill your building, the CO
2
sensor
detects their presence through increasing CO
2
levels and opens
the economizer appropriately.
When the occupants leave, the CO
2
levels decrease, and the
sensor appropriately closes the economizer. This intelligent
control of the ventilation air, called Demand Controlled Venti-
lation (DCV) reduces the overall load on the rooftop, saving
money.
Smoke detectors
Trust the experts. Smoke detectors make your application safer
and your job easier. Bryant smoke detectors immediately shut
down the rooftop unit when smoke is detected. They are avail-
able, installed by the factory, for supply air, return air, or both.
Louvered hail guards
Sleek, louvered panels protect the condenser coil from hail
damage, foreign objects, and incidental contact.
Convenience outlet (powered or un-powered)
Reduce service and/or installation costs by including a conve-
nience outlet in your specification. Bryant will install this ser-
vice feature at our factory. It provides a convenient, 15 amp,
115v GFCI receptacle with “Wet in Use” cover. The “powered”
option allows the installer to power the outlet from the line side
of the disconnect or load side as required by code. The “un-
powered” option is to be powered from a separate 115/120-v
power source.
Non-fused disconnect
This OSHA-compliant, factory-installed safety switch allows a
service technician to locally secure power to the rooftop.
Power exhaust with barometric relief
Superior internal building pressure control. This field-installed
accessory may eliminate the need for costly, external pressure
control fans.
RTU Open, multi-protocol controller
Connect the rooftop to an existing BAS without needing com-
plicated translators or adapter modules using the RTU Open
controller. This new controller speaks the 4 most common
building automation system languages (BACnet
1
, Modbus
2
,
N2, and LonWorks
3
). Use this controller when you have an
existing BAS.
Time Guard II control circuit
This accessory protects your compressor by preventing short-
cycling in the event of some other failure and prevents the com-
pressor from restarting for 30 seconds after stopping. Not
required with RTU Open or authorized commercial thermostats.
Motorized 2-position damper
The new Bryant 2-position, motorized outdoor air damper
admits up to 100% outside air. Using reliable, gear-driven tech-
nology, the 2-position damper opens to allow ventilation air and
closes when the rooftop stops, stopping unwanted infiltration.
Manual OA damper
Manual outdoor air dampers are an economical way to bring in
ventilation air. The dampers are available in 25% and 50%
versions.
Optional Perfect Humidity™ dehumidification system
Bryant’s Perfect Humidity dehumidification system is an all-
inclusive factory-installed option that can be ordered with any
Legacy Line 582J*04-06B rooftop unit.
This system expands the envelope of operation of Bryant’s
Legacy Line rooftop products to provide unprecedented flexi-
bility to meet year-round comfort conditions.
The Perfect Humidity dehumidification system has the indus-
try’s only dual dehumidification mode setting. The Perfect
Humidity system includes two new modes of operation.
The Legacy Line 582J*04-06B rooftop coupled with the Per-
fect Humidity system is capable of operating in normal design
cooling mode, subcooling mode, and hot gas reheat mode. Nor-
mal design cooling mode is when the unit will operate under its
normal sequence of operation by cycling compressors to main-
tain comfort conditions.
Subcooling mode will operate to satisfy part load type condi-
tions when the space requires combined sensible and a higher
proportion of latent load control. Hot Gas Reheat mode will
operate when outdoor temperatures diminish and the need for
latent capacity is required for sole humidity control. Hot Gas
Reheat mode will provide neutral air for maximum dehumidifi-
cation operation.
Motormaster
®
head pressure controller
The Motormaster motor controller is a low ambient, head pressure
controller kit that is designed to maintain the unit’s condenser head
pressure during periods of low ambient cooling operation. This
device should be used as an alternative to economizer free cooling
when economizer usage is either not appropriate or desired. The
Motormaster will either cycle the outdoor fan motors or operate
them at reduced speed to maintain the unit operation, depending
on the model.
1.
BACnet is a registered trademark of ASHRAE (American Society of
Heating, Refrigerating, and Air-Conditioning Engineers).
2.
Modbus is a registered trademark of Schneider Electric.
3.
LonWorks is a registered trademark of Echelon Corporation.
OPTIONS AND ACCESSORIES (CONT)