Wiring Connections; Outdoor Unit; Indoor Unit - Lennox MPA024S4S-*P Installation Instructions Manual

Torr).
4. Break the vacuum by allowing nitrogen into the port
connections (liquid and gas line pipes) until a positive
pressure is achieved
5. Evacuate the system to a minimum reading of 500
Microns (0.5 Torr).
6. For a moisture-free system, ensure the vacuum is held
without movement for a minimum of 4 hours.
7. If vacuum fails to hold, carry out steps 2 through 6 until
vacuum holds.

Wiring Connections

WARNING
Electric Shock Hazard. Can cause injury or death. Unit
must be rounded in accordance with national and local
codes.
Line voltage is present at all components when unit is
not in operation. Disconnect all remote electric power
supplies before opening access panel. Unit may have
multiple power sources.
CAUTION
All terminal connections must be made as illustrated
in the following diagrams. Improperly connected wiring
could damage unit or cause communication errors
between indoor and outdoor units.
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).

Outdoor Unit

• Refer to unit nameplate for minimum circuit ampacity
and maximum over-current protection size
• Make all electrical power wiring connections at the out-
door unit
• Be sure to reattach all electrical box covers after con-
nections are complete

Indoor Unit

• All indoor units are powered by the outdoor unit.
• Communication Wiring (Indoor Units 30K and Below):
Use one stranded 4-conductor wire to provide power
and communication
• Communication Wiring (Indoor Units 36K and Above):
Use one stranded 3-conductor wire to provide power
and one stranded 2-conductor wire to provide commu-
nication
• Use minimum of 18 GA stranded wiring
• When installing a condensate pump, wire in-line with
the CN5 float switch
IMPORTANT
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.
IMPORTANT
Install unit so that unit disconnect is accessible.
Use specified wiring and cable to make electrical
connections. Clamp cables securely and make sure that
connections 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.
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