Amana Bottom Mount Refrigerator Freezer Compartment Refrigeration Cycle Circuitry

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Electronic Functional Description

Circuitry

Refer to “Technical Data Sheet”, part #12074201, for Wiring Schematic.

Freezer Compartment Refrigeration Cycle Circuitry

As freezer thermistor warms, resistance lessons, allowing low voltage signal to be sent to electronic control. In turn, 2 low voltage signals are sent by electronic control. One to compressor relay coil (C1) and another to evaporator fan relay coil (F1). With both relay coils energized and contacts closed, high voltage circuits to compressor, condenser fan motor, and evaporator fan motor are complete.

As thermistor cools during refrigeration cycle, resistance through thermistor increases, blocking low voltage signal to electronic control, interrupting the cycle.

Fresh Food Compartment Refrigeration Cycle Circuitry

As fresh food thermistor warms, resistance lessens, allowing low voltage signal to be sent to electronic control. In turn, electronic control sends low voltage signal to 24 VDC fresh food fan.

When fresh food fan motor operates, freezer air is circulated into fresh food compartment. As fresh food thermistor cools, resistance increases, blocking low voltage signal to electronic control. In turn, electronic control interrupts the signal to fresh food fan motor.

Fresh Food and Freezer Compartment Refrigeration Cycle Circuitry

Many times cooling will be called for in both compartments as both freezer and fresh food thermistors warm. Resulting is electronic control signaling for compressor, condenser fan motor, evaporator fan motor, and 24 VDC fresh food fan to operate. Once freezer thermistor has been cooled sufficiently to block the signal to electronic control, the compressor, condenser fan motor, and evaporator fan motor will shut down. However, fresh food fan motor will continue to function until fresh food thermistor cools and blocks the signal to electronic control.

If fresh food thermistor is cooled prior to freezer thermistor, the electronic control will interrupt the signal to the fresh food fan motor. The compressor, condenser fan motor, and evaporator fan motor will remain in operation through freezer thermistor.

Adaptive Defrost Circuitry

After proper compressor run time (either 8, 12, or 16 hours), refrigeration cycle is interrupted and a low voltage signal is sent form electronic control to defrost relay coil (D1 DEF). Powering of relay coil closes relay contact (D1), completing the high voltage circuit to the defrost heater through the closed defrost terminator (closes at 20°F (-7°C)). The isolator, part of high voltage PC board, recognizes the presence of line voltage to the defrost heater. Isolator sends a low voltage signal to electronic control which keeps count of the number of minutes defrost terminator remains closed (opens at 55°F (13°C)). Length of time defrost terminator remains closed, determines whether next defrost cycle advances by 4 hours of compressor run, stays at same interval or backs up by 4 hours of compressor run. If defrost terminator does not open before 30 minutes, defrost cycle will automatically be terminated by electronic control and refrigeration cycle will resume after a 6 minute dwell time.

Important: When Showroom switch is off, isolator see's line voltage. In turn, isolator keeps electronic controller from signaling compressor, condenser fan motor, and evaporator fan motor relay coils and keeps fresh food fan motor off.

November 1996

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RS1200001

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Contents Bottom Mount Refrigerators ServiceSafety Symbols, Words, and Labels Safety and Electrical InformationElectrical Requirements Grounding InformationContents Ice Maker Installation Instructions UncratingSecuring Installation Instructions Door Panel Installation Water ConnectionRefrigerator Door 3/4 Raised Panel Hinge Adjustment Door Stop AdjustmentInterior Setup Freezer Door 3/4 Raised PanelSound Information Normal Operating SoundsFreezer and fresh food fan air rushes and whirs System Diagnosis Pressure and Relationship ChartRefrigerant Overcharge Symptoms Refrigerant Shortage SymptomsRestriction Symptoms Air in System Symptoms Low or High Ambient Temperature Installation SymptomsHeat Load Symptoms HFC134a Service Information Health, Safety, and HandlingComparison of CFC12 and HFC134a Properties Drier Replacement Service EquipmentCompressor Testing Procedures Replacement Service CompressorLeak Testing Refrigerant ChargeHFC134a Service Information Refrigerant Flow Air Flow Machine Compartment Assembly Component Function and Testing April RS1200001 Rev.1 Switch Continuity Functions Test Dpst Component Function and Testing Electronic Functional Description Keyboard Functions Electronic Testing ModeTemperature Control Operation Eeprom Update in Control Memory Power Up ConditionFactory set freezer and refrigerator settings Accessing Program ModeMode a Functions Freezer or Refrigerator Temperature Mode B FunctionsOperation Exiting Program Mode Electronic Functional Description VAC Freezer Compartment Refrigeration Cycle Circuitry CircuitryFresh Food Compartment Refrigeration Cycle Circuitry Adaptive Defrost CircuitryDoor Disassembly Procedures Cabinet Components Disassembly Procedures Condensate Drain Pan Chefs Pantry AssemblyShelf Support Ladders Refrigerator ThermistorMachine Compartment Disassembly Procedures Power Disconnect Switch Showroom SwitchCondenser Typical External Sweat Pattern Problem Possible Cause Troubleshooting GuideTroubleshooting Guide Testing Procedures SpecificationsIce Maker OperationDisassembly Procedures Water Fill Adjustment Accessing Control BoxEjector Blades or Stripper Wiring Harness Water ProblemsTemperature Problems ThermostatWater Valve No or Low Ice Production Problem Action Ice Maker Troubleshooting ChartEjector Position Excessive Ice Production Ice Maker Wiring Diagram and Parts Layout Parts List Introduction Recognize this symbol as a safety precautionB136CKR1 and B136CKL1 Custom Handle Kit B136CKR1Door Panels with Hinge on Right Side and Extruded Handle Panel DimensionsRefrigerator, Freezer Door Panel with Custom Handle inches 780 892 Radius 563 780 892 Radius 563 Freezer Drawer ProceduresB136CKR1 and B136CKL1 Custom Handle Kit B136SPK1 ¼ Facia Front Enclosure Kit Panel minimum depth Minimum height Side.186 Location of Panel Brackets on Side PanelsB136SPK1 ¼ Facia Front Enclosure Kit Procedures Bottom cabinet Panel Extrusion B136SPK1 ¼ Facia Front Enclosure Kit B136SPK2 ¾ Side Panel Kit Panel Dimensions Side view 11.281 500 062 Front Bottom Panel Bracket Front Panel Bracket Bottom RS1200001 November Procedure B136SPK2 ¾ Side Panel Kit
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