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Accessory Description and Usage
1. Low-Ambient Controller
This solid-state head pressure controller is a cycle control device activated by a temperature sensor. It is specifically designed to control outdoor fan motor run time in
response to saturated condensing temperature. For outdoor air temperatures between 55˚F and 0˚F (12.8˚C and –17.8˚C), it maintains condensing temperature at 75˚F
and 130˚F (23.8˚C and 54.4˚C).
SUGGESTED USE: Cooling operation at outdoor temperatures below 55˚F (12.8˚C).
2. Evaporator Freeze Thermostat
A SPST temperature actuated switch which stops unit operation when evaporator reaches freeze-up conditions.
SUGGESTED USE: With low-ambient controller (Item 1).
3. Isolation Relay
A SPDT relay which switches the low-ambient controller out of the outdoor fan motor circuit when the heat pump switches to heating mode.
SUGGESTED USE: All heat pumps where low-ambient controller (Item 1) has been added.
4. 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 chance of refrigerant slugging. May or may not include a thermostat control.
SUGGESTED USE: When interconnecting tube length exceeds 50 ft.
When unit will be operated below 55˚F (12.8˚C) outdoor air temperature. (Use with low-ambient controller, Item 1.)
All commercial installations.
5. Sound Blanket
Wrap around sound attenuation cover for the compressor. Reduces the sound level by about 0.2 bels.
SUGGESTED USE: Unit installed closer than 15 ft to quiet areas—bedrooms, etc.
Unit installed between 2 houses less than 10 ft apart.
6. Outdoor Thermostat
A SPDT temperature actuated switch which turns on supplemental electric heaters when outdoor air temperature drops below set point.
SUGGESTED USE: Heat pump installations with multiple-stage supplemental heaters.
7. Secondary Outdoor Thermostat
A SPDT temperature actuated switch which turns on a third-stage of supplemental electric heaters when outdoor air temperature drops below the second stage set point.
SUGGESTED USE: Heat pump installations where 3-stage operation of supplemental heaters is desired.
8. Service Alarm
A current-sensing lockout relay which provides immediate notification that compressor is not operating during a call for heating or cooling. Used with proper room
thermostat, the thermostat light is turned on signifying service is required. This can minimize electrical cost increase due to operation of supplemental heaters only.
SUGGESTED USE: As a feature to notify owner immediately when the system is not operating most efficiently.
9. Interface Control
An electric control for controlling a heat pump and gas or oil furnace system for maximum energy savings. It allows heat pump to operate down to a predetermined
economic balance point temperature, then switches to allow furnace operation only below that temperature. KHAIC0101AAA requires outdoor thermostat (Item 6).
SUGGESTED USE: All heat pump and gas- or oil-fired furnace combination systems.
10. Thermostatic Expansion Valve (TXV) Kits
A valve which meters refrigerant liquid flow rate into the evaporator in response to the superheat of the refrigerant gas leaving the evaporator. Kit includes valve (bi-flow
with integral check valve), adapter tubes and external equalizer tube.
SUGGESTED USE: For improved system performance in cooling mode.
All commercial installations.
11. Low-Pressure Switch
Auto reset SPST switch activated by refrigerant pressure in liquid line of refrigerant circuit. Cycles compressor off if refrigerant charge is lost.
SUGGESTED USE: Switch opens at 7 psig (+/– 3).
12. Liquid Solenoid Valve
An electrically operated shut-off valve which stops and starts refrigerant liquid flow in response to compressor operation. Maintains a column of refrigerant liquid ready
for action at next compressor operation cycle.
SUGGESTED USE: In certain long-line applications. (Refer to Long-Line Application Guideline.)
13. Support Feet
Four stick-on plastic feet which raise the unit 4 in. above the mounting pad. This allows sand, dirt and other debris to be flushed from the unit base; minimizes corrosion.
SUGGESTED USE: Coastal installations.
Windy areas or where debris is normally circulating.
Rooftop installations.
Sub-freezing climates.
14. Snow Rack
Coated wire rack which supports unit 18 in. above mounting pad to allow for drainage from unit base.
SUGGESTED USE: Heat pump installations in heavy snowfall areas.
Heat pump installations in snowdrift locations.
Heat pump installations in areas of prolonged subfreezing temperatures.
All commercial installations.
15. Time-Delay Relay
A SPST delay relay which briefly continues operation of the indoor blower motor to provide additional cooling after the compressor cycles off.
SUGGESTED USE: For improved efficiency ratings for certain combinations of indoor and outdoor units. (Refer to ARI Unitary Directory.)
