Carrier 48AK, 48EW, 48EY024-068, 48AW, 48AY020-060, 48EK, 48AJ, 48EJ specifications

TI T2 T3

SEE DETAIL B

DETAIL B

(SENSOR CONNECTION

LOCATION)

				R Y1 Y2 W1 W2 G C X
						SEE DETAIL A
					TB3
				DETAIL A
				(THERMOSTAT CONNECTION
				LOCATION)
			LEGEND
C	— Compressor/Contactor	FU	— Fuse	OFC	— Outdoor-Fan Contactor
CB	— Circuit Breaker	GND	— Ground	PEC	— Power Exhaust Controller
CCB	— Control Circuit Breaker	HR	— Heater Relay	PES	— Power Exhaust Sequencer
CCN	— Carrier Comfort Network	IFC	— Indoor-Fan Circuit	PESC	— Power Exhaust Sequencer Control-
					ler
CR	— Control Relay	IFCB	— Indoor-Fan Circuit Breaker	SIO	— Serial Input/Output
DIP	— Dual In-Line Package	IFR	— Indoor-Fan Relay	TB	— Terminal Block
EQUIP — Equipment		NEC	— National Electrical Code	TRAN	— Transformer

Thermostat Wiring (CV Only) — Install a Carrier-approved accessory thermostat assembly (per current price pages) according to the installation instructions included with the ac- cessory or these instructions. Locate the thermostat on a solid interior wall in the conditioned space to sense the average temperature.

Route the thermostat cable or equivalent single leads of colored wire from the subbase terminals to the low-voltage connection as shown on unit label wiring diagram and in Fig. 32.

NOTE: For wire runs up to 50 ft, use no. 18 AWG (American Wire Gage) insulated wire (35 C minimum). For 50 to 75 ft, use no. 16 AWG insulated wire (35 C minimum). For over 75 ft, use no. 14 AWG insulated wire (35 C minimum). All wire larger than no. 18 AWG cannot be directly connected at the thermostat and will require a junction box and splice at the thermostat.

Set heat anticipators to 0.1 for all voltages. Settings may be changed slightly to provide a greater degree of comfort for a particular installation.

Sensor Wiring (CV or VAV) — The temperature sensor is wired into the unit control board. See Fig. 33.

The unit is controlled with a T-55 or T-56 (CV only) zone sensor. Terminal TH (T-56) or T1 (T-55) on the sensor is con- nected to T1 of the base control board. Terminal COM (T-56) or T2 (T-55) on the sensor is connected to T2 on the base con- trol board. If a T-56 set point override sensor is used, the over- ride connection SW on the sensor is connected to T3 on the base control board.

If more than sensor is being used and averaged, sensors must be wired in multiples of 4 or 9. See Fig. 34.

Heat Interlock Relay — VAV units require a field-supplied heat interlock relay (HIR) to drive the air terminal wide open when in heat mode. Heat Interlock relay part number is HN61KK040. See Fig. 35 for HIR wiring.

Remote Field Control — A switch closure across terminals R and W1 on TB-3 will initiate the Occupied mode. This can be done manually as well as through a field-supplied timeclock.

Service Tool, Building Supervisor, and ComfortWORKS® Software — Access to the control board can be achieved through the terminal marked CCN via a 3-wire bus.

IMPORTANT: The default bus address is 0. The default element number is 1. Refer to CCN literature for informa- tion on network addressing or changing CCN communica- tion defaults.

Carrier Comfort Network Interface — The rooftop units can be connected to the CCN. The communication bus wiring is supplied and installed in the field. Wiring consists of shielded, 3-conductor cable with drain wire.

The system elements are connected to the communication bus in a daisy chain arrangement. The positive pin of each sys- tem element communication connector must be wired to the positive pins of the system element on either side of it, the neg- ative pins must be wired to the negative pins, and the signal pins must be wired to signal ground pins. Wiring connections for CCN should be made at the 3-pin plug (CCN located at the base board). Consult CCN literature for further information.

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