Bryant 549C manual GUIDE SPECIFICATIONS — 542J150,180 cont, J. Operating Characteristics

GUIDE SPECIFICATIONS — 542J150,180 (cont)

542J

J. Operating Characteristics:

1.Unit shall be capable of starting and running at 125 F ambient outdoor temperature, meeting maximum

load criteria of ARI Standard 210/240 or 360 at

+10% voltage.

2.Compressor with standard controls shall be capable of operation down to 40 F (in cooling mode) ambient outdoor temperature.

3.Compressor with standard controls shall be capable of operation down to –20 F (in heating mode) ambi- ent outdoor temperature.

4.Unit shall be capable of simultaneous heating duty and defrost cycle operation when using accessory electric heaters.

K.Electrical Requirements:

All unit power wiring shall enter unit cabinet at a single factory-predrilled location.

L.Motors:

1.Compressor motors shall be cooled by refrigerant gas passing through motor windings and shall have line break thermal and current overload protection.

2.Indoor-fan motor shall have permanently lubricated bearings and inherent automatic-reset thermal over- load protection.

3.Totally enclosed outdoor-fan motor shall have permanently lubricated bearings, and inherent automatic-reset thermal overload protection.

M.Special Features:

Certain features are not applicable when the features designated * are specified. For assistance in amending the specifications, contact your local Bryant Sales Office.

1.Roof Curbs (Horizontal and Vertical):

a.Formed galvanized steel with wood nailer strip and shall be capable of supporting entire unit weight.

b.Permits installation and securing of ductwork to curb prior to mounting unit on the curb.

2.Horizontal Adapter Roof Curb:

Includes factory-assembled adapter and duct.

NOTE: Power exhaust and barometric relief must be mounted in the return ductwork when used in con- junction with this accessory.

*3. Integrated Economizers:

a.Integrated integral modulating type capable of simultaneous economizer and compressor operation.

b.Available as a factory-installed option and accom- modates vertical or horizontal return air configura- tions. (Available as a field-installed accessory for dedicated horizontal and/or vertical supply return configurations.)

c.Includes all hardware and controls to provide cooling with outdoor air.

d.Equipped with low-leakage dampers, not to exceed 2% leakage at 1 in. wg pressure differential.

e.Capable of introducing up to 100% outdoor air.

f.EconoMi$erIV and EconoMi$er2 shall be equipped with a barometric relief damper.

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$erIV, the return air sen- sor, indoor humidity sensor, and outdoor humidity sensor shall be provided as field-installed acces- sories to provide enthalpy control, differential enthalpy control, and differential dry bulb temper- ature control. For the EconoMi$er2, the enthalpy, differential temperature (adjustable), and differen- tial 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 mini- mum 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 dampers shall be completely closed when the unit is in the occupied mode.

n.EconoMi$er2 Microprocessor Maximum 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 ventilation based on the optional 2 to 10 vdc CO2 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.

4.Barometric Relief Damper:

a.Package shall include damper, seals, hardware, and hoods to relieve excess internal pressure.

b.Damper shall close due to gravity upon unit shutdown.

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