Hoshizaki 73168 Removal and Replacement of Thermistors and Thermostat, Cabinet Thermistor

Page 52

H. Removal and Replacement of Thermistors and Thermostat

CAUTION

1.The thermistors are fragile; handle very carefully.

2.Do not shorten or cut the thermistor leads.

1.Cabinet Thermistor

1)Remove the refrigeration system cartridge. Perform steps 1 through 16 in "IV.B.2. Pump-Down Procedure." Once the refrigeration system cartridge is out, proceed to step 2.

2)Cut the cable tie holding the cabinet thermistor to the cabinet thermistor bracket. Remove the thermistor. See Fig. 5.

3)Disconnect the thermistor wire connector (below the control box).

4)Install the new thermistor and secure it to the cabinet thermistor bracket. Connect the thermistor connector.

5)Once the repair is complete, return to step 17 in "IV.B.2. Pump-Down Procedure" for refrigeration system cartridge replacement.

2.Defrost Thermistor

1)Remove the refrigeration system cartridge. Perform steps 1 through 16 in "IV.B.2. Pump-Down Procedure." Once the refrigeration system cartridge is out, proceed to step

2.

2)Remove the tape securing the defrost thermistor to the evaporator shroud. Cut the cable tie holding the defrost thermistor to the shroud. Remove the defrost thermistor. See Fig. 5.

3)Disconnect the defrost thermistor wire connector (below the control box).

4)Install the new defrost thermistor and secure to the evaporator shroud. Connect the defrost thermistor connector.

5)Once the repair is complete, return to step 17 in "IV.B.2. Pump-Down Procedure" for

refrigeration system cartridge replacement.

Defrost Thermistor

Defrost Thermostat

Evaporator Shroud

Cabinet Thermistor Bracket

Fig. 5

Cabinet Fan

Motors

Defrost Heater

Cabinet Thermistor

52

Image 52
Contents Superior Degree Reliability Number Issued Revised Hoshizaki AMERICA, INC Contents Page Page Important Safety Information Serious injuryIndicates important information about the use and care UnitSpecifications Nameplate Ratings DimensionsII. General Information Construction Power Switch ON, Rail Cooling Switch Normal or LOW Power Switch ON, Rail Cooling Switch OFFSequence of Operation Cool Down Restart Cabinet DefrostCabinet Defrost Power Switch ON, Rail Cooling Switch OFF Rail DefrostPower Switch ON, Rail Cooling Switch OFF Cabinet OperationPower Switch ON, Rail Cooling Switch Normal or LOW Position Rail CoolingCabinet and Rail Cooling Control Board Control Board LocationFront Rear Control Board LayoutLED Display and Service Lock-Out Alarm SignalService Menu Compressor Short Cycle ProtectionSwitch Settings Controls and AdjustmentsTemperature Display Energy Saving Mode Temperature SetpointCabinet Defrost Temperature Correction Factor Service Menu Service Menu AccessService Menu Chart Control Board Check Procedure Alarm SignalsControl Board Replacement Perimeter Heater Thermistor CheckCompressor Protector III. Service Diagnosis Alarm SignalsAlarm Priority Problem Reset, Corrections, and Adjustments High Temperature Alarm E1 Reset OptionsLow Temperature Alarm E2 Cabinet Defrost Alarm E3 High Condenser Temperature Alarm clogged filter E7 Possible Causes Defrost Thermistor cabinet Malfunction Alarm E85a. Secondary Defrost Thermistor Rail, not used Condenser Thermistor Malfunction Alarm E9 Control Board Alarms EA and ED Service ChartNo Operation Cabinet Cooling Problem Possible Cause Remedy Rail Cooling Cabinet Defrost Other Service for Refrigerant Lines IV. Removal and Replacement of ComponentsRefrigerant Recovery Brazing Evacuation and Recharge R-404APage Removal and Replacement of Refrigeration System Cartridge Refrigerant Recovery ProcedurePage Refrigeration System Pump‑Down Procedure Page Defrost Thermistor Rail Thermistor Removal and Replacement of Compressor Removal and Replacement of Cabinet Evaporator Removal and Replacement of Expansion Valve Removal and Replacement of Liquid Line Valve Removal and Replacement of Condenser Cabinet Thermistor Removal and Replacement of Thermistors and ThermostatDefrost Thermistor Defrost Thermostat Rail ThermistorRemoval and Replacement of Defrost Heater Condenser Thermistor clogged filterRemoval and Replacement of Fan Motors Cabinet Fan MotorCondenser Fan Motor Rail Fan MotorRemoval and Replacement of Door Gasket Door Re-Hinging and Drawer ConversionCleaning and Maintenance Instructions Work SurfaceRail and Rail Cover ExteriorCabinet Interior Door/Drawer GasketsMaintenance Power Supply ConnectionRail Condensate Pan Air FilterShutdown and Long Storage Refrigeration Circuit VI. Technical Information HPR100A-DWiring Diagrams HPR46A-D2a. HPR72A-D Auxiliary Code U-5 and Earlier 2b. HPR72A-D Auxiliary Code U-6 and Later Awaiting Data