Carrier 38YRA - Electrical Data

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Accessory description and usage (Listed alphabetically) continued

12. MotorMaster® Control

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, it maintains condensing temperature at 100°F ± 10°F.

SUGGESTED USE: Cooling operation at outdoor temperatures below 55°F.

All commercial installations.

13. Outdoor Thermostat

An 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.

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.

SUGGESTED USE: Heat pump installations where 3-stage operation of supplemental heaters is desired.

15. 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.

16. 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.

17. Sound Hood

Wraparound sound attenuation 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.

18. 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.

19. 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 evaporator. Kit includes

valve, adapter tubes, external equalizer tube.

SUGGESTED USE: For improved system performance in cooling mode for certain combinations of indoor and outdoor units. (Refer to ARI Unitary Directory.)

Required for use on all zoning systems.

20. 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.)

Electrical data

* Permissible limits of the voltage range at which unit will operate satisfactorily. Operation outside these limits may result in unit failure.

† Time-delay fuse or HACR Breaker.

‡ Length shown is as measured 1 way along the wire path between the unit and the service panel for voltage drop not to exceed 2%.

** If wire is applied at ambient greater than 30°C (86°F), consult Table 310-16 of the NEC (ANSI/NFPA 70). The ampacity of nonmetallic-sheathed cable (NM),

trade name ROMEX, shall be that of 60°C (140°F) conductors, per the NEC (ANSI/NFPA 70) Article 336-30.

If other than uncoated (non-plated), 60° or 75°C (140° or 167°F) insulation, copper wire (solid wire for 10 AWG and smaller, stranded wire for larger than

10 AWG) is used, consult applicable tables of the NEC (ANSI/NFPA 70).

NOTE: Control circuit is 24v on all units and requires external power source. Copper wire must be used from service disconnect to unit. All motors/compressors

contain internal overload protection.

UNIT SIZE-

SERIES V-PH

OPER VOLTS* COMPR

FAN

FLA MCA

MIN

WIRE

SIZE

60°C/75°C**

MAX

LENGTH