Hoshizaki 73168 service manual Temperature Setpoint, Cabinet Defrost, Energy Saving Mode

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c)Temperature Setpoint

The temperature setpoint is the temperature setting at which the compressor turns on. The factory default temperature setpoints are 37° (3°C) for the cabinet and 33°F (1°C) for the rail (see the chart below).

The temperature differential for the compressor to turn off is 3.6°F (2°C) below the temperature setpoint. The temperatures are updated every 30 seconds. If necessary, adjust the temperature setpoint as outlined below.

Note: The cabinet and rail temperature setpoints must be changed individually.

1)Press the appropriate "SET" button to display the current temperature setpoint.

2)Press and hold the appropriate "SET" button while pressing the up or down arrow button. See the chart below for temperature setpoint ranges.

3)Release the "SET" button. As long as the unit is not turned off, the new setpoint will be saved automatically after 10 seconds.

Section

Temperature Setpoint Range

Default

Cabinet

21 to 53°F

37°F

(-6 to +12°C)

(3°C)

 

Rail

-13 to +53°F

33°F

(-25 to +12°C)

(1°C)

 

d)Cabinet Defrost

The automatic cabinet defrost is factory set for once every 6 hours. See "II.D.5. Service Menu." The cabinet defrost thermistor will signal the control board to start a defrost once the 6 hour defrost timer has expired and the cabinet evaporator temperature is below 49°F (9.4°C). Defrost is heated, and therefore will have a tendency to raise the cabinet temperature.

For a manual cabinet defrost press the "MANUAL DEFROST" button on the control board for 5 seconds to initiate a defrost. This will restart the 6-hour defrost timer.

Cabinet temperature is not displayed during defrost; "dF" is displayed in its place. The control board will terminate the cabinet defrost and begin defrost recovery when a signal from the cabinet defrost thermistor is greater than 49°F (9.4°C). After defrost, there is a 5minute delay before the compressor will start.

This unit has an additional defrost thermistor located behind the wire cover that connects to the K201 connector, terminals 3 and 4. This thermistor is not used for defrost purposes on this model, but must be in place for proper operation of the control board.

e)Energy Saving Mode

"Energy Saving Mode" is not used on this unit. The "Energy Saving Mode" LED is located to the bottom right of the cabinet display and should be off. See "II.D.2. Control Board Layout." If the "Energy Saving Mode" LED is on, press the "SERVICE USE ONLY" button for 5 seconds to exit and disable the "Energy Saving Mode."

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Contents Superior Degree Reliability Number Issued Revised Hoshizaki AMERICA, INC Contents Page Page Unit Important Safety InformationSerious injury Indicates important information about the use and careDimensions Specifications Nameplate RatingsII. General Information Construction Power Switch ON, Rail Cooling Switch Normal or LOW Power Switch ON, Rail Cooling Switch OFFSequence of Operation Cabinet Defrost Cool Down RestartRail Defrost Cabinet Defrost Power Switch ON, Rail Cooling Switch OFFOperation Power Switch ON, Rail Cooling Switch OFF CabinetRail Cooling Power Switch ON, Rail Cooling Switch Normal or LOW PositionCabinet and Rail Cooling Control Board Location Control BoardControl Board Layout Front RearCompressor Short Cycle Protection LED Display and Service Lock-OutAlarm Signal Service MenuSwitch Settings Controls and AdjustmentsTemperature Display Energy Saving Mode Temperature SetpointCabinet Defrost Temperature Correction Factor Service Menu Access Service MenuService Menu Chart Control Board Check Procedure Alarm SignalsControl Board Replacement Perimeter Heater Thermistor CheckCompressor Protector Alarm Signals III. Service DiagnosisAlarm Priority Problem Reset, Corrections, and Adjustments Reset Options High Temperature Alarm E1Low 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 Evacuation and Recharge R-404A BrazingPage Refrigerant Recovery Procedure Removal and Replacement of Refrigeration System CartridgePage 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 Rail Thermistor Defrost ThermostatCondenser Thermistor clogged filter Removal and Replacement of Defrost HeaterCabinet Fan Motor Removal and Replacement of Fan MotorsRail Fan Motor Condenser Fan MotorDoor Re-Hinging and Drawer Conversion Removal and Replacement of Door GasketWork Surface Cleaning and Maintenance InstructionsDoor/Drawer Gaskets Rail and Rail CoverExterior Cabinet InteriorAir Filter MaintenancePower Supply Connection Rail Condensate PanShutdown and Long Storage HPR100A-D Refrigeration Circuit VI. Technical InformationHPR46A-D Wiring Diagrams2a. HPR72A-D Auxiliary Code U-5 and Earlier 2b. HPR72A-D Auxiliary Code U-6 and Later Awaiting Data