Hoshizaki HWR68A(-D), HWR40A(-D), HUR96A(-D) Defrost Temperature Sensor Malfunction Alarm E8

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f. Defrost Temperature Sensor Malfunction Alarm (E8)

If input from the defrost thermistor is below the defrost open circuit detection point (equivalent to -67°F (-55°C)), "E8" is displayed. "E8" is also displayed when input from the defrost thermistor is above the defrost thermistor short circuit detection point (equivalent to 122°F (50°C)) for 10 minutes or more.

Note:

•If this alarm appears, first make sure that the sensor is properly connected.

•A short circuit will not be detected during the first hour after power is turned on. However, a short circuit can be detected immediately by turning on the power

while pressing the button. In this case, "E8" will be displayed immediately if a short circuit is detected.

• A short circuit will not be detected during defrost or fan delay.

Reset Options

The alarm automatically resets when one of the following conditions is met:

•The input from the defrost thermistor exceeds the open circuit detection point (equivalent to -67°F (-55°C)).

•The input from the defrost thermistor drops below the short circuit detection point (equivalent to 122°F (50°C)).

•A functioning defrost thermistor (orange) is installed.

Possible Causes

• Trouble with the defrost thermistor (orange).

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Contents Superior Degree Reliability Energy Star Contents Page Specifications Nameplate Ratings DimensionsUndercounter Model Names HUR40A, HUF40A Units mm 1a. HUR40A-D, HUF40A-D 2a. HWR40A-D, HWF40A-D HWR40A, HWF40A3a. HUR68A-D, HUF68A-D HUR68A, HUF68A4a. HWR68A-D, HWF68A-D HWR68A, HWF68AHUR96A Units mm 5a. HUR96A-D HWR96A Units mm 6a. HWR96A-D Evaporator Case II. General Information ConstructionSequence of Operation and Timing Charts Refrigerators Continuous Operating ModeSequence of Operation Operating Timing ChartFreezers Continuous Operating Mode Freezers Continuous Defrost End Defrost thermistor reaches defrost Refrigerators Energy Saving Operating ModeEnergy Board Self Check Minute Delay Freezers Energy Saving Operating ModeFreezers Energy Control Board Start-Up DelayFront Relay Wiring Harness K311Thermistor Wiring Harness K151 RearGaining Access to Settings and Diagnostics Settings and DiagnosticsTemperature Display Switching the Display Between Fahrenheit and Celsius F5Adjusting the Setpoint Temperature Cabinet Temperature Correction calibration factor Later Section Settings and Diagnostics MenuDefrost Interval F0 Defrost Termination Temperature F1Setpoint Temperature Differential F2 Low Temperature Alarm Delay Time F4 High Temperature Alarm Delay Time F3Alarm History F6 Temperature Display Scale F5Operating Modes Compressor Run Time F7Perimeter Frame Heater ContinuousEnergy Saving Alarm Signals Alarm Code Problem III. Service Diagnosis Alarm CodesError Code Priority Description Alarm Display PriorityPossible Causes Alarm Details and CountermeasuresHigh Temperature Alarm E1 Reset OptionsLow Temperature Alarm E2 High Pressure Alarm E4 Defrost Alarm E3Clogged Filter Alarm E7 Defrost Temperature Sensor Malfunction Alarm E8 Clogged Filter Sensor Malfunction Alarm E9 Control Board Error Alarms EA and ED Problem Possible Cause Remedy Diagnosis ChartProblem Possible Cause Remedy Problem Possible Cause Remedy Thermistor Check Brazing IV. Removal and Replacement of ComponentsService for Refrigerant Lines Refrigerant RecoveryEvacuation and Recharge Removal and Replacement of Compressor Removal and Replacement of Refrigeration UnitRemoval and Replacement of Evaporator Page Page Clogged Filter Thermistor sensor Removal and Replacement of ThermistorsCabinet Thermistor Defrost ThermistorRemoval and Replacement of Defrost Heater Removal and Replacement of Door GasketRemoval and Replacement of Control Board Evaporator Fan Motor Removal and Replacement of Fan MotorsDoor Re-Hinging and Drawer Conversion Condenser Fan MotorCleaning Cleaning and Maintenance InstructionsDrawers MaintenanceAir Filter Shelves115/60/1 A2. HUR40A-D, HWR40A-D auxiliary code Q6 and later HUF40A-D, HWF40A-D C1. HUR68A, HWR68A auxiliary code Q5 and earlier C2. HUR68A-D, HWR68A-D auxiliary code Q6 and later HUF68A-D, HWF68A-D HUR96A-D, HWR96A-D