Carrier 69NT40-541-001, Operation And Service

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T-316 7–24
e. Remove middle coil support.
f. Remove the mounting hardware from the coil.
g. Unsolder the two coil connections, one at the distributor and the other at the coil header.
h. After defective coil is removed from unit, remove defrost heaters and install on replacement coil.
i. Install coil assembly by reversing above steps.
j. Leak check connections per Section 7.5 . Evacuate the unit per Section 7.6 and add refrigerant charge
per Section 7.7 .
7.15.2 Evaporator Heater Replacement
a. Before servicing unit, make sure the unit circuit breakers (CB-1 & CB-2) and the start-stop switch (ST) are in
the OFF position, and that the power plug and cable are disconnected.
b. Remove the lower access panel ( Figure 3.1 ) by removing the T.I.R. locking device lockwire and mounting
screws.
c. Determine which heater(s) need replacing by checking resistance on each heater. Refer to Section 3.3 for
heater resistance values
d. Remove hold-down clamp securing heaters to coil.
e. Lift the bent end of the heater (with the opposite end down and away from coil). Move heater to the side
enough to clear the heater end support and remove.
7.16 EVAPORATOR FAN AND MOTOR ASSEMBLY
The evaporator fans circulate air throughout the container by pulling air in the top of the unit. The air is forced
through the evaporator coil where it is either heated or cooled and then discharged out the bottom of the refrigera-
tion unit into the container. The fan motor bearings are factory lubricated and do not require additional grease.
7.16.1 Replacing The Evaporator Fan Assembly
WARNING
!
Always turn OFF the unit circuit breakers (CB-1 & CB-2) and disconnect main power supply
before working on moving parts.
a. Remove upper access panel (see Figure 3.2 ) by removing mounting bolts and T.I.R. locking device. Reach
inside of unit and remove the Ty-Rap securing the wire harness loop. Then unplug the connector by twisting
to unlock and pulling to separate.
b. Loosen four 1/4-20 clamp bolts that are located on the underside of the fan deck at the sides of the of the
fan assembly. Slide the loosened clamps back from the fan assembly.
c. Slide the fan assembly out from the unit and place on a sturdy work surface.
7.16.2 Disassemble The Evaporator Fan Assembly
a. Attach a spanner wrench to the two 1/4-20 holes located in the fan hub. Loosen the 5/8-18 shaft nut by hold-
ing the spanner wrench stationary and turning the 5/8-18 nut counterclockwise (see Figure 7.22 ).
b. Remove the spanner wrench. Use a universal wheel puller and remove the fan from the shaft. Remove the
washers and key.
c. Remove the four 1/4-20 x 3/4 long bolts that are located under the fan that support the motor and stator
housing. Remove the motor and plastic spacer.