Bryant 549B - Manual (Page 71)

71
GUIDE SPECIFICATIONS — 548F036-120 (cont)
f. EconoMi$erIV and EconoMi$er2 shall be equipped
with a barometric relief damper capable of relieving
up to 100% return air.
g. Designed to close damper(s) during loss-of-
power situations with spring return built into
motor.
h. Dry bulb outdoor-air temperature sensor shall be
provided as standard. Outdoor air sensor set
point is adjustable and shall range from 40 to
100 F. For the EconoMi$erIV, the return air sen-
sor, indoor enthalpy sensor, and outdoor enthalpy
sensor shall be provided as field-installed
accessories to provide enthalpy control, differen-
tial enthalpy control, and differential dry bulb
temperature control. For the EconoMi$er2, the
enthalpy, differential temperature (adjustable),
and differential enthalpy control shall be provided
as field-installed accessories.
i. The EconoMi$erIV and EconoMi$er2 shall have a
gear-driven parallel blade design.
j. EconoMi$erIV microprocessor control shall pro-
vide control of internal building pressure through
its accessory power exhaust function. Factory set
at 100%, with a range of 0% to 100%.
k. EconoMi$er2 shall be capable of control from a 4
to 20 mA signal through optional 4 to 20 mA
design without microprocessor control (required
for third party control interface).
l. EconoMi$erIV Microprocessor Occupied Mini-
mum Damper Position Setting maintains the
minimum airflow into the building during occupied
period providing design ventilation rate for full
occupancy (damper position during heating). A
remote potentiometer may be used to override
the set point.
m. EconoMi$erIV Microprocessor Unoccupied Mini-
mum Damper Position Setting — The
EconoMi$erIV damper shall be completely closed
when the unit is in the occupied mode.
n. EconoMi$erIV Microprocessor IAQ/DCV Maxi-
mum Damper Position Setting — Setting the
maximum position of the damper prevents the
introduction of large amounts of hot or cold air
into the space. This position is intended to satisfy
the base minimum ventilation rate.
o. EconoMi$erIV Microprocessor IAQ/DCV control
modulates the outdoor-air damper to provide ven-
tilation based on the optional 2 to 10 vdc CO
2
sensor input.
p. Compressor lockout sensor (opens at 35 F,
closes at 50 F).
q. Actuator shall be direct coupled to economizer
gear, eliminating linkage arms and rods.
r. Control LEDs:
1) When the outdoor-air damper is capable of
providing free cooling, the “Free Cool” LED
shall illuminate.
2) The IAQ LED indicates when the module is on
the DCV mode.
3) The EXH LED indicates when the exhaust fan
contact is closed.
s. Remote Minimum Position Control — A field-
installed accessory remote potentiometer shall
allow the outdoor-air damper to be opened or
closed beyond the minimum position in the occu-
pied mode for modified ventilation.
3. 50% Manual Outdoor-Air Damper:
Manual damper package shall consist of damper,
birdscreen, and rainhood which can be preset to
admit up to 50% outdoor air for year-round
ventilation.
4. 100% Manual Outdoor-Air Damper:
Manual damper package shall consist of damper
birdscreen, and rainhood which can be preset to
admit up to 100% outdoor air for year-round
ventilation.
* 5. 100% Two-Position Damper:
a. Two-position damper package shall include single
blade damper. Admits up to 100% outdoor air.
b. Damper shall close upon indoor fan shutoff.
c. Designed to close damper during loss of power
situations.
d. Equipped with barometric relief damper.
* 6. 25% Two-Position Damper:
a. Two-position damper package shall include single
blade damper and motor. Admits up to 25% out-
door air.
b. Damper shall close upon indoor fan shutoff.
* 7. Electric Resistance Heaters:
a. Open wire nichrome elements with all necessary
safety operating controls.
b. UL listed and indicated on basic unit informative
plate.
c. Available in multiples to match heating
requirements.
d. Single point kits available for each heater when
required.
* 8. Head Pressure Control Packages:
Package shall consist of solid-state control and out-
door-coil temperature sensor to maintain condensing
temperature between 90 F and 110 F at outdoor
ambient temperatures down to –20 F by outdoor fan
speed modulation or outdoor fan cycling.
* 9. Thermostat and Subbase:
Thermostat and subbase provide staged cooling and
heating automatic (or manual) changeover, fan con-
trol, and indicator light.
10. Thru-The-Bottom Utility Connections:
Kit shall provide connectors to permit electrical con-
nections to be brought to the unit through the
basepan.
* 11. Electronic Programmable Thermostat:
Unit shall be capable of using deluxe full-featured
electronic thermostat. Thermostat shall use built-in
compressor cycle delay control for both heating and
cooling duty. Thermostat shall be capable of working
with third party direct digital controls.
548F