Electrical - Lennox Signature XP21 Series Installation And Service Procedure

IMPORTANT
Use a thermocouple or thermistor electronic vacuum
gauge that is calibrated in microns. Use an instrument
capable of accurately measuring down to 50 microns.
WARNING
Danger of Equipment Damage. Avoid deep vacuum
operation. Do not use compressors to evacuate a
system. Extremely low vacuums can cause internal
arcing and compressor failure. Damage caused by
deep vacuum operation will void warranty.
Evacuating the system of non−condensables is critical for
proper operation of the unit. Non−condensables are de-
SIZE CIRCUIT AND INSTALL DISCONNECT
1
SWITCH
REFER TO THE UNIT NAMEPLATE FOR MINIMUM CIRCUIT AMPACITY,
AND MAXIMUM FUSE OR CIRCUIT BREAKER (HACR PER NEC).
INSTALL POWER WIRING AND PROPERLY SIZED DISCONNECT
SWITCH.
SERVICE
DISCONNECT
SWITCH
NOTE UNITS ARE APPROVED FOR USE ONLY WITH COPPER
CONDUCTORS. GROUND UNIT AT DISCONNECT SWITCH OR TO AN
EARTH GROUND.
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.
CAUTION
ELECTROSTATIC DISCHARGE
(ESD)
Precautions and Procedures
XP21
fined as any gas that will not condense under temperatures
and pressures present during operation of an air condition-
ing system. Non−condensables and water suction combine
with refrigerant to produce substances that corrode copper
piping and compressor parts.

Electrical

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
Use the transformer provided with the furnace or air han-
dler for low-voltage control power (24VAC − 40 VA
minimum)
2
NOTE
CONTROL BOX.
Electrostatic discharge can affect electronic components. Take precautions
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.
Neutralize electrostatic charge by touching hand and all tools on an unpainted
unit surface before performing any service procedure
Page 22
INSTALL THERMOSTAT
INSTALL ROOM THERMOSTAT (ORDERED SEPARATELY) ON AN
INSIDE WALL APPROXIMATELY
CONDITIONED AREA AND 5 FEET (1.5M) FROM THE FLOOR. IT
SHOULD NOT BE INSTALLED ON AN OUTSIDE WALL OR WHERE IT
CAN BE AFFECTED BY SUNLIGHT OR DRAFTS.
THERMOSTAT
5 FEET
(1.5M)
24VAC, CLASS II CIRCUIT CONNECTIONS ARE MADE IN THE
IN THE CENTER OF THE