Lennox International Inc Dave Lennox Signature Collection XC21 System 24VAC TRANSFORMER

STEP 5 −− ELECTRICAL −− Circuit Sizing and Wire Routing

In the U.S.A., wiring must conform with current local codes and the current National Electric Code (NEC). In Canada, wiring must conform with current local codes and the current Canadian Electrical Code (CEC).

Refer to the furnace or air handler installation instructions for additional wiring application diagrams and refer to unit nameplate for minimum circuit ampacity and maximum overcurrent protection size.

24VAC TRANSFORMER

IMPORTANT !

If unit is equipped with a crankcase heater, it should be energized 24 hours before unit start−up to pre- vent compressor damage as a result of slugging.

CAUTION

Use the transformer provided with the furnace or air han- dler for low-voltage control power (24VAC − 40 VA mini- mum)

WARNING

Electric Shock Hazard. Can cause injury or death. Unit must be grounded in accordance with national and local codes.

Line voltage is present at all components when unit is not in operation on units with single-pole contactors. Disconnect all remote electric power supplies before opening access panel. Unit may have multiple power supplies.

ELECTROSTATIC

DISCHARGE

(ESD)

Precautions and

Procedures

Electrostatic discharge can affect electronic components. Take care during unit installation and service to protect the unit’s electronic controls. Precautions will help to avoid control exposure to electrostatic discharge by putting the unit, the control and the technician at the same electrostatic potential. Touch hand and all tools on an unpainted unit surface before performing any service procedure to neutralize electrostatic charge.

SIZE CIRCUIT AND INSTALL DISCONNECT

1SWITCH

Refer to the unit nameplate for minimum circuit ampacity, and maximum fuse or circuit breaker size (HACR per NEC). Install power wiring and properly sized disconnect switch.

SERVICE

DISCONNECT

SWITCH

2INSTALL THERMOSTAT

Install room thermostat (ordered separately) on an inside wall in the center of the conditioned area and 5 feet (1.5m) from the floor. The thermostat should not be installed on an outside wall or where it can be affected by sunlight or drafts.

THERMOSTAT

5 FEET

(1.5M)

NOTE Units are approved for use only with copper conductors. Ground unit at disconnect switch or connect to an earth ground.

NOTE AC, Class II circuit connections are made in the control box.

FIGURE 12

Page 11

XC21 SERIES