Lennox International Inc Lennox Air Handler Airflow Cooling Blower Speed, Change Blower Speed

THERMOSTAT		AIR HANDLER
	R			THERMOSTAT	AIR HANDLER
	G				R
SEE		BU			G
NOTE			SEE		BU
			NOTE		W
	Y
				HEAT‐ONLY APPLICATION
		AIR
		CONDITIONER	THERMOSTAT			HEAT PUMP
		UNIT			AIR HANDLER	UNIT
	COOLING‐ONLY APPLICATION				R
	THERMOSTAT	AIR HANDLER			G
	R
	G		CONNECT COMMON		BU
			WIRE ONLY IF
			REQUIRED
		W	(REFER TO THE
			APPROPRIATE
			THERMOSTAT		BK
		BK	INSTALLATION
			INSTRUCTIONS)
SEE		BU			W
	Y
NOTE
		AIR CONDITIONER		HEAT PUMP APPLICATION WITH
					ELECTRIC HEAT
		UNIT
	COOLING APPLICATION WITH
	ELECTRIC HEAT
NOTE - Connect common wire only if required (Refer to the appropriate thermostat installation instructions)

Figure 12. Low Voltage Connections (3-Speed PSC Motor) - Field Wiring

Airflow — Cooling Blower Speed

The cooling blower speed is factory configured to provide correct airflow for an outdoor unit that matches the cooling capacity rating of the air handler.

If the outdoor unit is smaller than the maximum cooling capacity rating for the air handler, the cooling blower speed may need to be changed. Refer to blower performance chart, table 2 on page 11 .

WARNING

Electric shock hazard! - Disconnect all power supplies before servicing.

Replace all parts and panels before op­ erating.

Failure to do so can result in death or elec­ trical shock.

CHANGE BLOWER SPEED

1.Disconnect all power supplies.

2.Remove the air handler access panel.

3.Locate pin number 2 on the blower relay. Two black wires are connected to this terminal pin. One connects to pin number 5 on the blower relay, one connects to an in-line splice connecting to a red wire.

4.Remove the wire going to the 4-pin blower motor connector from the splice.

5.Connect the blower lead [Red (LO), Black (HI)] onto the splice from the 4-pin blower motor connector.

NOTE — Reuse the factory-installed plastic cap on whichever wire is not used.

6.Replace all panels.

7.Reconnect power.

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