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19
Run Power Wiring for Indoor Unit
Be sure field wiring complies with local building codes and NEC,
and unit voltage is within limits shown in Tables 17 through 20.
Contact the local power company for correction of improper line
voltage.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position.
There may be more than 1 disconnect switch. Lock out and
tag switch with a suitable warning label.
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
Unit failure as a result of operation on improper line voltage or
excessive phase imbalance constitutes abuse and may cause
damage to electrical components. Such operation could void
any applicable manufacturer warranty.
NOTE
:
Use copper wire only between disconnect switch(es)
and unit.
NOTE
:
Install a branch circuit disconnect of adequate size to
handle the unit starting current per NEC. Locate the
disconnect within sight of, and readily accessible to the unit,
per section 440--14 of NEC. Some codes allow the indoor unit
to share a disconnect with the outdoor unit if the disconnect
can be locked; check local codes before installing in this
manner.
The 40MKCB**C and 40MKQB**C units require their own
power supply.
1. Locate the indoor power supply.
2. Locate and install disconnect switch per NEC and local
codes.
3. Run power supply wiring to disconnect switch.
4. Run power wiring from disconnect switch to the cassette
control box. Use copper wire only.
5. If any accessories are being installed, refer to the individual
accessory instructions for guidance on wire routing at this
time.
Install All Power, Interconnecting Wiring, Piping and
Drain Hose to Indoor Unit
1. Run the control wiring from the outdoor unit through the
access hole in the wall and make sure you have enough wire
to reach the control box of the unit once hung from the sus-
pension bolts.
2. Complete all refrigerant piping connections.
a. Cut the extreme end of the tubes and remove any
copper shavings with a deburring blade.
b. Remove the flare nut from the “Flare” connection body
of the indoor unit and insert them into the pipes.
c. Make the flares to the pipe ends with the proper flaring
tool. The flare end must not have any burrs or
imperfections. The flared walls must be uniform (see
Fig. 39 and Fig. 40).
A01799
Fig. 39 -- Removing Burrs
L
L
A07200
Fig. 40 -- Flared Walls as Equal
3. It is recommended that flare connections be located on the
outside of the wall where the indoor unit is to be mounted. If
an extension pipe is required to facilitate this location, measure,
fabricate and install the extension pipes to the indoor unit
before hanging the unit.
4. If piping connections are on the outside wall, pass the pipes
(refrigerant and drain) through the wall sleeve. Support the
unit away from the bottom using a tool or a piece of wood.
2
3
2
3
A08364
Fig. 41 -- Location of Piping, Hose, and Wiring
5. Route the power and control wiring through the back side
of the unit and to the control box area. If the wired remote is
to be used, perform any modifications required at this time.
Refer to the Accessory installation instructions.