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ACCESSORY DESCRIPTION AND USAGE (Listed Alphabetically)
1.
Ball-Bearing Fan Motor
A fan motor with ball bearings which permits speed reduction while maintaining bearing lubrication.
Usage Guideline:
Required on all units when MotorMaster®—Low-Ambient Controller is installed.
2.
Coastal Filter
A mesh screen inserted under the top cover and inside the base pan to protect the condenser coil from salt damage without restricting airflow.
3.
Compressor Start Assist – Capacitor and Relay
Start capacitor and relay gives a "hard" boost to compressor motor at each start up.
Note:
Heat pumps with Puron-refrigerant and a reciprocating compressor have capacitor and relay factory supplied.
Usage Guideline:
Required for single-phase reciprocating compressors in the following applications:
Long line
Low ambient cooling
Hard shut off expansion valve on indoor coil
Required for single-phase scroll compressors in the following applications:
Long line
Low ambient cooling
Suggested for all compressors in areas with a history of low voltage problems.
4.
Compressor Start Assist — PTC Type
Solid state electrical device which gives a "soft" boost to the compressor at each start-up.
Usage Guideline:
Suggested in installations with marginal power supply.
5.
Crankcase Heater
An electric resistance heater which mounts to the base of the compressor to keep the lubricant warm during off cycles. Improves compressor lubrication
on restart and minimizes the chance of liquid slugging.
Note:
Some heat pumps are factory supplied with a crankcase heater. See accessory list for units that come standard with a crankcase heater. For units
that do not, use the guideline below.
Usage Guideline:
Required in low ambient cooling applications.
Required in long line applications.
Suggested in all commercial applications.
6.
Evaporator Freeze Thermostat
An SPST temperature-actuated switch that stops unit operation when evaporator reaches freeze-up conditions.
Usage Guideline:
Required when low ambient kit has been added.
7.
Isolation Relay
An SPDT relay which switches the low-ambient controller out of the outdoor fan motor circuit when the heat pump switches to heating mode.
Usage Guideline:
Required in all heat pumps where low ambient kit has been added.
8.
Liquid-Line Solenoid Valve (LLS)
An electrically operated shutoff valve which stops and starts refrigerant liquid flow in response to compressor operation. It is to be installed at the outdoor
unit to control refrigerant off cycle migration in the heating mode.
Usage Guideline:
An LLS is required in all long line heat pump applications to control refrigerant off cycle migration in the heating mode. See Long Line
Application Guideline.
9.
Low-Ambient Pressure Switch
A long life pressure switch which is mounted to outdoor unit service valve. It is designed to cycle the outdoor fan motor in order to maintain head pressure
within normal operating limits (approximately 200 psig to 365 psig). The control will maintain working head pressure at low-ambient temperatures down to
0°F (–17.8°C) when properly installed.
Usage Guideline:
A Low-Ambient Pressure Switch or MotorMaster ®—Low-Ambient Controller must be used when cooling operation is used at outdoor tem-
peratures below 55°F (12.8°C).
10.
MotorMaster®—Low-Ambient Controller
A fan-speed control device activated by a temperature sensor designed to control condenser fan motor speed in response to the saturated, condensing
temperature during operation in cooling mode only. For outdoor temperatures down to –20°F (–28.9°C), it maintains condensing temperature at 100°F ±
10°F (37.8°C ± –12°C).
Usage Guideline:
A MotorMaster ®—Low-Ambient Controller or Low-Ambient Pressure Switch must be used when cooling operation is used at outdoor tem-
peratures below 55°F (12.8°C).
Suggested for all commercial applications
11.
Outdoor Air Temperature Sensor
Designed for use with Bryant Thermostats listed in this publication. This device enables the thermostat to display the outdoor temperature. This device also
is required to enable special thermostat features such as auxiliary heat lock out .
Usage Guideline:
Suggested for all Bryant thermostats listed in this publication.
12.
Outdoor Thermostat
An SPDT temperature-actuated switch which turns on supplemental electric heaters when outdoor air temperature drops below a user-selected set point.
Usage Guideline:
Electric supplemental heat applications in non-variable speed indoor units when electric heat staging is desired.
13.
Pressure Guard Kit
A pressure switch kit that cycles the outdoor fan to limit the heating head pressure below a pre-determined pressure setting.
Usage Guideline:
Some local codes may require limiting the heating head pressure in the vapor line in some applications.
14.
Secondary Outdoor Thermostat
An SPDT temperature-actuated switch which turns on third-stage of supplemental electric heaters when outdoor air temperature drops below the second-
stage set point.
Usage Guideline:
Outdoor thermostat applications where electric heater is capable of 3-stage operation.
