Lenox Elite Series XP16 Units Heat Pumps Test, 24VAC, Dis−Yel, Amb−Black, Coil−Brown, Delay, Out

Table 9. Demand Defrost Control (A108) Inputs, Outputs and Configurable Settings

Control	Control Label or	Purpose	Function
Locations	Description
P1	TEST	Test Mode	See Test Mode on page 39 for further details.
		Defrost Temperature	The demand defrost control as illustrated in figure 25 has valid selections
			which are: 50, 70, 90, and 100°F (10, 21, 32 and 38°C). The shunt
P1	50, 70, 90, 100	Termination Shunt (Jumper)
			termination pin is factory set at 50°F (10°C). If the temperature shunt is
		Pins
			not installed, the default termination temperature is 90°F (32°C).
	W1	24VAC Thermostat Input /	24VAC input / output from indoor thermostat to indoor unit.
		Output
	C	24VAC Common	24VAC common
	L	Thermostat Service Light	Thermostat service light connection.
P2
	R	24VAC	24VAC
	Y2	Thermostat Input	Controls the second stage operation of the unit.
	O	Thermostat Input	Reversing valve solenoid.
	Y1	Thermostat Input	Controls the operation of the unit.
P3	55, 50, 45, 40	Low Ambient Thermostat	Provides selection of the Y2 compressor lock−in temperature. Valid
		Pins	options are 40, 45, 50 and 55 degrees Fahrenheit.
	DIS−YEL	Coil Sensor	(P4−5) Ground connection for outdoor coil temperature sensor.
			(P4−6) Connection for outdoor coil temperature sensor.
P4	AMB−BLACK	Ambient Sensor	(P4−3) Ground connection for outdoor ambient temperature sensor.
			(P4−4) Connection for outdoor ambient temperature sensor.
	COIL−BROWN	Discharge Sensor	No discharge sensor is used; replaced by 10K resistor.
			The demand defrost control has a field−selectable function to reduce
			occasional sounds that may occur while the unit is cycling in and out of
			the defrost mode. When a jumper is installed on the DELAY pins, the
P5	DELAY	Delay Mode	compressor will be cycled off for 30 seconds going in and out of the
			defrost mode. Units are shipped with jumper installed on DELAY pins.
			NOTE − The 30 second off cycle is NOT functional when TEST pins on
			P1 are jumpered.
P6	TST, PS DF, C, R, O, Y1, Y2	Factory Test Connectors	No field use.
DS1	RED LED		Valid states for demand defrost control two LEDs are OFF, ON and
		Diagnostic LED	FLASHING which indicate diagnostics conditions that are described in
DS2	GREEN LED
			table 10.
FAN	TWO CONNECTORS	Condenser Fan Operation	These two connections provide power for the condenser fan.
O OUT	O OUT	24 VAC output	24 VAC output connection for reversing valve.
			When the low pressure switch trips, the demand defrost control will cycle
			off the compressor, and the strike counter in the demand defrost control
			will count one strike. The low pressure switch is ignored under the
			following conditions:
LO−PS	LO−PS	Low−Pressure Switch	S	during the defrost cycle and 90 seconds after the termination of
				defrost
			S when the average ambient sensor temperature is below 0°F (−18°C)
			S for 90 seconds following the start up of the compressor
			S	during TEST mode
Y2 OUT	Y2 OUT	24 VAC Output	24 VAC output for second stage compressor solenoid.
Y1 OUT	Y1 OUT	24 VAC Common Output	24 VAC common output, switched for enabling compressor contactor.
			When the high pressure switch trips, the demand defrost control will cycle
HS−PS	HS−PS	High−Pressure Switch	off the compressor, and the strike counter in the demand defrost control
			will count one strike.
L	L	Service Light Output	24VAC service light output.
24V	24V	24 Volt output	24VAC typically used to supply power to the Lennox System Operation
			Monitor (LSOM). Not used in this system.

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XP16 SERIES