5
Accessory usage guideline
* For tubing line sets greater than 50 ft horizontal and/or 20 ft vertical differential, refer to Residential Split System Long-Line Application Guideline
and Service Manual.
† Only when low-pressure switch is used.
‡ Required for MotorMaster® Control only.
ACCESSORY
REQUIRED FOR
LOW-AMBIENT
APPLICATIONS
(Below 55°F)
REQUIRED FOR
LONG-LINE
APPLICATIONS*
(Over 50 Ft)
REQUIRED FOR
SEA COAST
APPLICATIONS
(Within 2 Miles)
Crankcase Heater
Yes
Yes
No
Evaporator Freeze Thermostat
Yes
No
No
Winter Start Control
Yes†
No
No
Accumulator
No
No
No
Compressor Start Assist
Capacitor and Relay
Yes
Yes
No
MotorMaster® Low-Ambient Controller
or Low-Ambient Pressure Switch
Yes
No
No
Wind Baffle
See Low-Ambient Instructions
No
No
Coastal Filter
No
No
Yes
Support Feet
Recommended
No
Recommended
Liquid-Line Solenoid Valve
or
Hard Shutoff TXV
No
See Long-Line
Application
Guideline
No
Ball Bearing Fan Motor
Yes‡
No
No
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 low-ambient controller (full modulation feature) or 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.
Usage Guideline:
Required for reciprocating compressors in the following applications:
Long line
Low ambient
Hard shut off expansion valve on indoor coil
Liquid line solenoid on indoor coil
Required for scroll compressors in the following applications:
Long line
Low ambient
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 reciprocating 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.
Usage Guideline:
Required in low ambient 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.
Liquid-Line Solenoid Valve (LLS)
This device serves two purposes. It is an electrically operated shutoff valve which stops and starts refrigerant liquid flow in response to compressor operation.
It maintains a column of refrigerant liquid ready for action at next compressor operation cycle. It also provides system protection against off-cycle refrigerant
migration.
Note:
When LLS is used with reciprocating compressors, Compressor Start Assist — Capacitor and Relay is required.
Usage Guideline:
Required in air conditioner long line applications with a piston indoor metering device to prevent off cycle refrigerant migration. A hard shut
off TXV can be used instead of an LLS in single flow air conditioner applications. See Long Line Application Guideline.
8.
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.
