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may not need to do all of the following:
from the 31-9091 service manual:
The fresh food compartment receives chilled air via an electronic damper
that is positioned at the top rear of the fresh food compartment.
The damper is controlled by the main control board and when open,
allows the evaporator fan to push chilled air from the evaporator
into the fresh food compartment.
To Remove the Damper
1. Remove the light cover.
2. Remove 4 Phillips screws and the light assembly.
3. Remove the Styrofoam section covering the damper.
4. Disconnect the damper wiring connector.
5. Carefully pull the damper out of the mullion and remove.
Access to the Evaporator:
To Remove the Evaporator Fan
1. Remove the ice bucket.
2. Disconnect the icemaker connector.
Loosen 2 screws and remove icemaker.
3. Remove 4 screws and slide the icemaker drive motor assembly forward.
Disconnect the wiring connector and remove the assembly.
4. Remove 2 screws and inner section of left ice bucket track.
5. Remove 2 screws and wiring cover.
6. Remove 6 screws and evaporator fan cover.
7. Disconnect the evaporator fan wiring connector.
8. Remove 2 screws from the fan mounting bracket and remove the fan.
Caution: Use care to avoid scratching the finish on unit walls.
The defrost heater is a single calrod-type, radiant heater mounted on the evaporator.
To remove the defrost heater:
1. Remove the evaporator fan.
2. Remove 8 screws and freezer ceiling panel.
3. Remove Styrofoam insulation from the bottom of the evaporator drain pan.
4. Loosen evaporator drain hose clamp.
5. Lower left side of evaporator drain pan and slide right side out of drain hose and remove.
6. Disconnect the heater wiring.
7. Remove 2 screws from the left and right heater fasteners.
8. Slide the heater toward the front of the freezer compartment and remove.
Source: Monogram ziss420d