Bryant 581A/B - Manual (Page 143)

143
GUIDE SPECIFICATIONS — 580F036-151 AND 581B036-150 (cont)
23. Return Air Enthalpy Sensor (EconoMi$er IV or
EconoMi$er2):
The return air enthalpy sensor shall be used with the
EconoMi$er IV or EconoMi$er2 device. When used
in conjunction with an outdoor air enthalpy sensor,
the EconoMi$er IV or EconoMi$er2 device will pro-
vide differential enthalpy control.
24. Return Air Temperature Sensor (EconoMi$er IV or
EconoMi$er2):
The return air temperature sensor shall be used with
the EconoMi$er IV or EconoMi$er2 device. When
used in conjunction with the standard outdoor air tem-
perature sensor, the EconoMi$er IV or EconoMi$er2
device will provide differential temperature control.
25. Indoor Air Quality (CO
2
) Sensor (EconoMi$er2):
a. Shall have the ability to provide demand ventila-
tion indoor air quality (IAQ) control through the
EconoMi$er2 with an IAQ sensor.
b. The IAQ sensor shall be available in duct mount,
wall mount, and wall mount with LED display. The
set point shall have adjustment capability.
c. Requires EconoMi$er2 control option.
26. Indoor Air Quality (CO
2
) Room Sensor (EconoMi$er
IV):
Sensor shall have the ability to provide demand ven-
tilation control through the EconoMi$er IV. The IAQ
sensor shall be wall mounted with an LED display in
parts per million. The set point shall have adjustment
capability.
27. Return Air CO
2
Sensor (EconoMi$er IV):
Sensor shall have the ability to provide demand ven-
tilation control through the EconoMi$er IV. The IAQ
sensor shall be duct mounted. The set point shall
have adjustment capability.
28. Gas Heat options (sizes 004-006):
a. Single-stage gas heat shall be provided in lieu of
two-stage heat.
b. NOx reduction shall be provided to reduce nitrous
oxide emissions to meet the California Air Quality
Management NOx requirement of 40 nanograms/
joule or less.
c. Primary tubes on low NOx units shall be 409
stainless steel. Other components shall be alumi-
nized steel.
29. Ultraviolet Germicidal Lamps:
Ultraviolet germicidal lamps are designed to elimi-
nate odor causing mold and fungus that may develop
in the wet area of the evaporator section of the unit.
The high output, low temperature germicidal lamps
are field installed in the evaporator section of the
unit, aimed at the evaporator coil and condensate
pan. The short wavelength ultraviolet light inhibits
and kills mold, fungus and microbial growth. The
lamps have an output rating at 45F in 400 fpm airflow
of 120 microwatts/cm
2 at 1 meter.
30. Perfect Humidity™ Adaptive Dehumidification Sys-
tem (581B only):
a. The Perfect Humidity dehumidification system
shall be factory-installed in the rooftop units, and
shall provide greater dehumidification of the occu-
pied space by two modes of dehumidification
operations beside its normal design cooling
mode:
1) Subcooling mode further subcools the hot liq-
uid refrigerant leaving the condenser coil when
both temperature and humidity in the space
are not satisfied.
2) Hot gas reheat mode shall mix a portion of the
hot gas from the discharge of the compressor
with the hot liquid refrigerant leaving the con-
denser coil to create a two-phase heat transfer
in the system, resulting in a neutral leaving-air
temperature when only humidity in the space is
not satisfied.
b. The system shall consist of a subcooling/reheat
dehumidification coil located downstream of the
standard evaporator coil. This dehumidification
coil is a two-row coil with the exception of the 036
unit, which has a one-row coil.
c. The system shall include crankcase heater(s) for
the scroll compressor(s).
d. The system shall include a low outdoor air tem-
perature switch to lock out both subcooling and
hot gas reheat mode when the outdoor-air tem-
perature is below 40 F.
e. The system shall include a Motormaster® low
ambient control to ensure the normal design cool-
ing mode capable of down to 0° F low ambient
operation.
f. The system shall include a low-pressure switch
on the suction line to ensure low pressure start-
up of hot gas reheat mode at lower outdoor tem-
perature condition.
g. The system operation may be controlled by a
field-installed, wall-mounted humidistat. The
dehumidification circuit will then operate only
when needed. Field connections for the humidis-
tat are made in the low-voltage compartment of
the unit control box. The sensor can be set for any
level between 55% and 80% relative humidity.
h. The system shall include a thermostatic expan-
sion valve (TXV) to ensure a positive superheat
condition and a balance of pressure drop.
i. For units with two compressors (sizes 090-150),
depending on the conditions required to maintain
the space set points, one or both compressors
can operate in subcooling mode, one compressor
could operate in subcooling mode while the other
operates in hot gas reheat mode, or one or both
compressors can operate in hot gas reheat mode.
31. Humidistat:
Field-installed, wall-mounted humidistat is used to
control activation of the dehumidification package.
The humidistat can be set for humidity levels
between 20% and 80% relative humidity.
32. Hinged Panel Option:
Hinged panel option provides hinged access panels
for the filter, compressor, evaporator fan, and control
box areas. Filter hinged panels permit tool-less entry
for changing filters. Each hinged panel is perma-
nently attached to the rooftop unit.
33. Louvered Hail Guard:
The hail guard shall protect the entire outdoor coil
surface from direct or indirect (from adjacent sur-
faces) hail damage. Hail guard shall have a pressure
drop of 2%.
58
0F0
3
6
-15
1 AND 58
1B036
-1
50