Power Wiring For Outdoor And Indoor Units (Diagrams) - Lennox MPA009S4S Service Manual

10. Power Wiring for Outdoor and Indoor Units (Diagrams)

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 com-
pleted.
Install all wiring at least 3 feet (1 m) away from televisions, radios or other electronic devices in order to avoid the
possibility of interference with the unit operation.
Do not install the unit near a lighting appliance that includes a ballast. The ballast may affect remote control
operation.
Isolate the power supply before accessing unit electrical terminals.
Install unit so that unit disconnect is accessible.
Follow all local and national codes, as well as this installation instruction, during installation. Do NOT overload
electrical circuit, as this may lead to failure and possible fire.
Use specified wiring and cable to make electrical connections. Clamp cables securely and make sure that con-
nections are tight to avoid strain on wiring. Insecure wiring connections may result in equipment failure and risk
of fire. Wiring must be installed so that all cover plates can be securely closed.
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 unit nameplate for minimum circuit ampacity and maximum over-current protection size.
• All indoor units are powered by the outdoor unit.
• Communication wiring is determined by the indoor unit size. Indoor units 30k and below use one stranded
4-conductor wire to provide power and communication.
Indoor units 36k and above use one stranded 3-conductor wire to provide power and one stranded 2-conductor wire
to provide communication.
NOTE: Multi-zone systems use indoor units sizes 24k and below.
• Make all electrical power wiring connections at the outdoor unit.
• Use minimum of 18 GA stranded wiring.
• Connect wiring from outdoor unit to indoor unit.
• Refer to unit name plate for rated voltage.
• Be sure to reattach all electrical box covers after connections are complete.
• Follow NEC/CEC standards and all local and state codes during wiring installation.
CAUTION
WARNING
52