Carrier 48EW, 48EY024-068, 48AW, 48AY020-060, 48EK, 48AK, 48AJ, 48EJ DIP Switch Configuration

•DIP switch 6 configures the Time Guard® override and, when used with the field test function, sets the minimum damper position

•DIP switch 7 configures the unit for gas heat or electric heat

•DIP switch 8 configures the unit for heat pump or air conditioner operation.

Crankcase Heater — Units are equipped with crank- case heaters. Crankcase heaters are energized as long as there is power supplied to unit. Crankcase heaters deenergize while compressors are running.

IMPORTANT: To prevent damage to compressors, crank- case heater should be energized 24-hours prior to start-up.

Evaporator Fan — Fan belt and fixed pulleys are factory-installed. See Tables 19-33 for fan performance and motor limitations data. Remove tape from fan pulley, and be sure that fans rotate in the proper direction. See Table 34 for air

quantity limits. Static pressure drop for power exhaust is negli- gible. To alter fan performance, see Evaporator Fan Perfor- mance Adjustment section on page 91.

Condenser Fans and Motors — Condenser fans and motors are factory set. Refer to Condenser-Fan Adjustment section on page 92 as required. Be sure that fans rotate in the proper direction. Fan no. 2 (48AJ,AK,AW,AY020-030 and 48EJ,EK,EW,EY024-034), fans no. 3 and 4 (48AJ,AK,AW, AY035-050 and 48EJ,EK,EW,EY038-054), and fans no. 4, 5, and 6 (48AJ,AK,AW,AY060 and 48EJ,EK,EW,EY058-068) are cycled on the outdoor-air temperature.

The VFD will always provide the proper phase sequence to the indoor-fan motor to operate in the proper rotation regard- less of the phase sequence to the unit. If on start-up, the outdoor fans operate backwards but the indoor fan operates in the cor- rect direction, reverse any two leads to the unit main terminal block and all fans will operate in the correct direction.

Table 16A — Power Exhaust Default Set Points (48AJ,AK,AW,AY020-050 and 48EJ,EK,EW,EY024-048)

STAGE	OFFSET	DIFFERENTIAL	OFF VOLTAGE	ON VOLTAGE	OFF STATIC PRESSURE
					(in.wg)
1	50%	3%	6.0	6.3	0.00
2	55%	3%	6.5	6.8	0.06
3	60%	3%	7.0	7.3	0.12
4	64%	3%	7.4	7.7	0.18

Table 16B — Power Exhaust Default Set Points (48AJ,AK,AW,AY060 and 48EJ,EK,EW,EY054-068)

STAGE	OFFSET	DIFFERENTIAL	OFF VOLTAGE	ON VOLTAGE	OFF STATIC PRESSURE
					(in.wg)
1	50%	3%	6.0	6.3	0.00
2	55%	3%	6.5	6.8	0.06
3	60%	3%	7.0	7.3	0.12
4	65%	3%	7.5	7.8	0.19
5	70%	3%	8.0	8.3	0.25
6	75%	3%	8.5	8.8	0.31

Table 17 — DIP Switch Configuration

SETTING	1	2	3	4	5	6	7	8
					VAV —
		VAV — Space Sensor			Occupied	Time Guard® Override
		Installed			Heat	ON
OPEN	VAV		Expansion	Field Test	Enabled		Gas Heat	Heat Pump
			Board	ON	CV —	IN CONJUNCTION		Operation
		CV — CCN or Sensors			Modulated	WITH FIELD TEST
		Used			Power	— Set Minimum
					Exhaust	Damper Position
					VAV —
		VAV — No Space Sensor			Occupied
					Heat
			Base Control	Field Test	Disabled	Time Guard Override		Air Conditioner
CLOSED	CV				CV —		Electric Heat
			Board Only	OFF		OFF		Operation
					Constant
		CV — Thermostat			Volume
					Power
					Exhaust

LEGEND

CCN — Carrier Comfort Network

CV — Constant Volume

VAV — Variable Air Volume

NOTES:

1.The OPEN side of the DIP switch is marked ‘‘OPEN.’’ When the rocker switch is on the ‘‘OPEN’’ side of the switch, the switch is OPEN.

2.The configuration of DIP switches 2 and 5 are dependent on DIP switch 1. If DIP switch 1 is set to OPEN (VAV operation), then DIP switches 2 and 5 will configure VAV functions.

3.When the unit is field-tested (DIP switch 4 to OPEN), the func- tion of DIP switch 6 changes and it is used to set the minimum damper position.

4.Recycle power to unit after modifying DIP switches. This will allow the unit to access the new configurations and update its tables.

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