Lennox MCA Series Installation Instructions Manual page 14

This unit must be properly grounded and protected by a circuit breaker. The ground wire for the unit must not be
connected to a gas or water pipe, a lightning conductor or a telephone ground wire.
Do not connect power wires to the outdoor unit until all other wiring and piping connections have been completed.
Do not install the unit near a lighting appliance that includes a ballast. The ballast may affect remote control operation.
Systems and Terminal
Designations
Indoor to Outdoor Wiring
(Communication/Power)
1, 2, 3 and GND
Outdoor to Main Power
L, N and GND
Indoor to Outdoor Wiring
(Communication/Power)
1, 2, 3 and GND
Indoor to Outdoor Wiring
(Communication/Power)
1, 2, 3 and GND
Outdoor to Main Power
L1, L2 and GND
Indoor to Outdoor Wiring
(Communication/Power)
1, 2, 3 and GND
Outdoor to Main Power
L1, L2 and GND
MCA = Minimum Circuit Amps
IMPORTANT
Table 7. Single Zone Installation Wiring Requirements
System Capacity System Voltage
12K
12K
09K 208/230VAC
12K 208/230VAC
09K and 12K 208/230VAC
18K and 24K 208/230VAC
18K and 24K 208/230VAC
Number of
Conductors
115VAC 4
115VAC 3
4
4
3
4
3
14
Wire Type Wire Gauge / MCA
16AWG
14AWG / 15A
16AWG / 10A
Stranded and
16AWG / 11A
unshielded
16AWG / 9A
16AWG
14AWG / 18A