York Air Handler Manuals: Installation, Operation, and Maintenance Guide

262675-UIM-A-0806

NOTE: All wiring must comply with local and national electrical code			FUNCTIONALITY AND OPERATION
requirements. Read and heed all unit caution labels.			Jumper Positions
NOTE: It is possible to vary the amount of electric heat turned on during
			Heat Enable Jumper
the defrost cycle of a heat pump. Standard wiring will only bring on the
first stage of electric heat during defrost. See Heat Output and Limit			The HEAT ENABLE jumper configures the control for heat kit operation.
Connections and Table 6 for additional information on heat during			The jumper must be in the HEAT position if a heat kit is installed with
defrost cycle.			the air handler.
TABLE 2: Low Voltage Connections			With the jumper in the NO HEAT position, the control will not energize
			the heat relay outputs or sense the limit switch input.
Terminal	Signal	Comment
			If the jumper is not present, the control will operate as if the jumper is in
R	24 VAC power (fused)
			the HEAT position. If the jumper is not present and a heat kit is not
G	Continuous Fan operation
			present, the control will sense an open limit condition and the blower
	Second or full stage
Y/Y2			will run continuously.
	compressor operation
			Hum Stat Jumper
Y1	First stage compressor	Not used with outdoor units
	operation	having one stage compressors.	The HUM STAT jumper configures the control to monitor the humidity
W2	Second stage heat operation
			switch input. With the jumper in the NO position, the control will ener-
W1	First stage heat operation
			gize the HUM terminal with 24 VAC continually. With the jumper in the
		24 VAC will be present at this
			YES position, the control will monitor the HUM input to control the HUM
O	Reversing valve operation	terminal when the MODE
			OUT output to control an external humidifier.
		jumper is in the AC position.
		This is normal.	If the jumper is not present, the control will operate as if the jumper is in
		24 VAC will be present at this	the YES position.
HUM	Humidity switch input	terminal when the HUM STAT	Mode Jumper
		jumper is in the NO position.
		This is normal.	The MODE jumper configures the control to operate properly with an air
	Connection point for	This terminal is a connection
			conditioner (AC position) or heat pump (HP position). With the jumper in
X/L		point only and does not affect
	heat pump fault indicator		the AC position, the control will energize the O terminal with 24 VAC
		air handler control operation.
			continually. With the jumper in the HP position, the O input signal is
COM	24 VAC common
			received from the room thermostat.
The low voltage connections may be connected to the screw terminals
			If the jumper is not present, the control will operate as if the jumper is in
or the quick connect terminals. The screw terminals and the quick con-
			the HP position.
nect terminals are physically connected on the control board.
			SPARE Jumper
HUMIDITY SWITCH INPUT
			The control includes a spare jumper that can be used if a jumper is lost.
The air handler control is designed to work with a humidity control that
			The SPARE jumper does not have any effect on the operation of the
closes when the humidity is below the set-point. The control is open			control.
when the humidity is above the set-point. This humidity control may be			Status and Fault Codes
referred to as a humidistat or a dehumidistat.
			The control includes an LED that displays status and fault codes. These
The humidity switch controls both humidification and de-humidification
			codes are shown in Table 3. The control will display the fault codes until
operation of the control. The control provides humidification using the
			power is removed from the control or the fault condition is no longer
HUM OUT relay output and de-humidification by lowering the blower
			present.
speed. This is accomplished using the LOW FAN output and a field
installed two-speed fan relay kit for non-variable speed models and the			TABLE 3: Fault Codes
de-humidification input of the motor for variable speed models. The
humidity switch should be connected to the R and HUM terminals of the			Fault or Status Condition	LED1 (RED)
control. See Figures 10 & 11.				Flash Code
SECTION VI: REQUIRED CONTROL			Status
			No power to control	OFF
SET-UP
			Normal operation	2s ON / 2s OFF
IMPORTANT: The following steps must be taken at the time of installa-
			Control in test mode	Rapid Flash
tion to insure proper system operation.
			Control failure	ON
1. Consult system wiring diagram to determine proper thermostat
			Limit Faults
wiring for your system.
			Limit switch currently open (not in lockout)	1
2. If heat kit is installed, change HEAT ENABLE jumper from NO
			Multiple limit openings with no call for heat	2
HEAT to HEAT position.
3. If a humidstat is installed, change HUM STAT jumper from NO to			Multiple limit openings during one call for heat	3
			Single long duration limit opening	4
YES.
4. Set the MODE jumper to A/C (Air Conditioner) or HP (Heat Pump)			Multiple long duration limit openings	5
position depending on the outdoor unit included with the system.			Fan failure	6
			Wiring Related Faults
			Simultaneous call for heating and cooling	7
			Internal Control Faults
			Control recovered from internal event	9

6 Unitary Products Group