Bryant 581A - Manual (Page 3)

FIELD-INSTALLED ACCESSORY DESCRIPTION AND USAGE (cont)
Thermostats and Subbases — Provide staged cooling and
heating, automatic (or manual) changeover, fan control, and in-
dicator light.
SUGGESTED USE:
• To control unit operations.
Enthalpy Control Sensor — Package consists of a solid-state
sensor to be paired with a second enthalpy sensor for differen-
tial enthalpy control. This sensor is mounted on the economizer
assembly so that it can sense building return-air temperature.
The 2 sensors will determine which combination of outdoor and
return air will provide the greatest energy savings.
SUGGESTED USE:
• To enhance economizer operation for maximum energy
savings.
NOTE: A single sensor may be used for single-sensor, outdoor-
air, enthalpy control if desired.
Time Guard ா II Device — Package consists of a control to be
field wired into the unit controls, and provides a 5-minute delay
in compressor operation between cooling cycles.
SUGGESTED USE:
• Prevents compressor short cycling when rapid compressor
cycles may be a problem.
Head Pressure Control Device — Kit consists of an outdoor-
air thermostat that permits adequate head pressure control dur-
ing cooling operation at low outdoor-ambient temperatures.
Refer to Trade Prices for more details or contact your local
representative.
SUGGESTED USE:
• When cooling at low-ambient outdoor temperatures is
desired.
Low-Ambient Kit — Kit consists of a solid-state control and
condenser coil temperature sensor to modulate the condenser-
fan motors in order to maintain condenser-coil head pressure
for proper cooling operation. Refer to Trade Prices for more de-
tails or contact your local representative.
SUGGESTED USE:
• Whenever cooling is required at low outdoor ambient tem-
peratures (as low as –20 F).
• Low-ambient kit is not usually required when economizer is
used.
Barometric Relief Package — This package is useful when it
is necessary to remove excess pressure from the conditioned
space.
NOTE: Optional economizer is required.
SUGGESTED USE:
• When the job requires the ability to relieve internal building
pressure.
Power Exhaust Package — This package is useful when it is
necessary to remove excess pressure from the conditioned
space.
NOTE: Optional economizer is required.
SUGGESTED USE:
• When the job requires the ability to relieve internal building
pressure and pressure losses through the return-air ductwork
are greater than 0.20 in. wg.
• When the job requires the ability to move large quantities of
air to relieve pressure in the conditioned space.
Winter Start Time Delay Relay — Used in conjunction with ac-
cessory low-ambient kit or head pressure control device, per-
mits operation in cooling at lower outdoor ambient tempera-
tures. See Trade Prices for more details or contact your local
representative.
SUGGESTED USE:
• When job requires the ability to operate in cooling at low
outdoor-ambient temperatures.
MODEL DESCRIPTION
(ODS Model Number)
LEGEND
ODS — Order Distribution System
3