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ACCESSORY DESCRIPTION AND USAGE (Listed Alphabetically) Continued
13. Secondary Outdoor Thermostat
An 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.
14. 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.
15. Snow Stand
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.
16. Sound Hood
Wraparound sound reducing cover for the compressor. Reduces unit sound level by about 2 dBA.
SUGGESTED USE: Unit installed closer than 15 ft to quiet areas—bedrooms, etc.
Unit installed between 2 houses less than 10 ft apart.
17. 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.
18. Thermostatic Expansion Valve (TXV)—Bi-flow
A modulating flow control valve which meters refrigerant liquid flow rate into the evaporator in response to the superheat of the refrigerant gas leaving the evap-
orator. Kit includes valve, adapter tubes, and external equalizer tube.
SUGGESTED USE: Required for improved system performance. (Refer to ARI Unitary Directory.)
Required for use on all zoning systems.
19. Time-Delay Relay
An 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.)
