Hoshizaki KM-901MAH, KM-901MWH, KM-901MRH/3 service manual Removal and Replacement of Thermistor

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Thermistor Holder

8)Braze all fittings with nitrogen gas flowing at a pressure of 3 to 4 PSIG.

9)Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). DO NOT use R-404A as a mixture with pressurized air for leak testing.

10)Evacuate the system and charge it with refrigerant. See the rating label inside the icemaker, for the required refrigerant charge.

11)Replace the panels in their correct positions.

12)Turn on the power supply.

L.Removal and Replacement of Thermistor

This section covers removal and replacement of the thermistor. For a thermistor check procedure, see "IV.E. Thermistor Check."

CAUTION

1.The thermistor is fragile; handle very carefully.

2.Always use the recommended sealant (high thermal conductive type), Model KE4560RTV manufactured by SHINETSU SILICONE, Part Code 60Y00011, or Part Code 4A0683-01 or equivalent.

3.Always use the recommended foam insulation (non-absorbent type) or equivalent.

4.Do not shorten or cut the thermistor leads.

1)Turn off the power supply.

2)Remove the panels.

3)Remove the control box cover.

4)Disconnect the white thermistor connector from the control board WHITE K3 connector.

5)Remove the plastic cable ties, foam insulation, thermistor holder, and thermistor. See

Fig. 5.

Thermistor Lead

Cable Tie

6)Scrape away the old sealant on the thermistor holder and the suction pipe.

7)Wipe off moisture or condensation on the suction pipe.

8)Smoothly apply recommended sealant (KE4560RTV, Part Code 60Y000-11 or 4A068301) to the thermistor holder concave.

Foam Insulation

Fig. 5

9)Attach the new thermistor to the suction pipe in the same position as the previous thermistor. Be very careful to prevent damage to the leads. Secure it using the thermistor holder and recommended foam insulation.

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Contents KM-901MAH KM-901MWH Hoshizaki AMERICA, INC Contents Page Page Unit Important Safety InformationSerious injury Indicates important information about the use and care1a. KM-901MAH air-cooled Auxiliary Code T-0, U-0 Specifications Icemaker1b. KM-901MAH air-cooled Auxiliary Code U-1 and Later Water Cooled Condenser 2a. KM-901MWH water-cooled Auxiliary Code T-0, U-02b. KM-901MWH water-cooled Auxiliary Code U-1 and Later 3a. KM-901MRH remote air-cooled Auxiliary Code T-0, U-0 3b. KM-901MRH remote air-cooled Auxiliary Code U-1 and Later 4a. KM-901MRH3 remote air-cooled Auxiliary Code T-0, U-0 4b. KM-901MRH remote air-cooled Auxiliary Code U-1 and Later Condenser Unit Model URC-9F SpecificationsKM-901MAH air-cooled II. General Information ConstructionKM-901MWH water-cooled KM-901MRH/3 remote air-cooled Sequence Cycles and Shutdown Sequence of OperationControl Board Auxiliary Code T-0, U-0 Control Board Auxiliary Code U-1 and Later ShutdownOFF Cycle at Shutdown Mechanical Bin Control Activation Bin Full Control Board Sequence Flow ChartSequence Flow Chart CycleFill Cycle Control Board Auxiliary Code U-1Later Minute Harvest Cycle Freeze Cycle Pump-Out CycleControl Board Control Board Control Board LayoutPart Number 2A3792-01 Maximum Water Supply Period 6 minutes Harvest Backup Timer and Freeze TimerHigh Temperature Safety Low Water SafetyEnergized Time LEDs are On Components Min Max Avg LED Lights and Audible Alarm SafetiesNo. of Beeps Type of Alarm Every 3 sec Sequence StepControl Board Auxiliary Code U-1 and Later S4 Dip Switch S4 Dip Switch No Controls and AdjustmentsDefault Dip Switch Settings Harvest Timer S4 dip switch 1Pump-Out Frequency Control S4 dip switch 5 Pump-Out Timer S4 dip switch 3S4 Dip Switch Setting Time seconds Inlet Control Board S4 Dip Switch Setting Pump Motor Time seconds Bin Control Selector/Harvest Pump Timer S4 dip switchFactory Use S4 dip switch Control Board S4 Dip Switch Setting Bin ControlS4 Dip Switch Setting Time Minutes Freeze Timer S4 dip switch 9Float Switch Control S5 dip switch 1 G Control Board Refill Counter S5 dip switch 2 through 5 G Control BoardThermistor Float SwitchControl Switch Bin ControlWater Pump Switch Discharge Line ModelCooled-AirWater-Cooled Model PressureHigh* Switch Wiring DiagramsKM-901MAH air-cooled and KM-901MWH water-cooled KM-901MRH remote air-cooled PressureSwitchHigh KM-901MRH3 remote air-cooled Cooled-AirModel High* Pressure Switch Cooled-WaterModelHigh Pressure Switch SwitchPressure Performance Data 1570 912835 1480KM-901MRH remote air-cooled KM-901MRH3 remote air-cooled Diagnostic Procedure IV. Service DiagnosisPage OFF Shutdown Thermostatic Bin Control Auxiliary Code T-0, U-0 Control Board CheckControl Correct LED Board Lighting Sequence Bin Control CheckMechanical Bin Control Check Mechanical Bin Control Cleaning Float Switch Check Float Switch Check and CleaningFloat Switch Cleaning Thermistor Check Problem Possible Cause Remedy Diagnostic ChartsNo Ice Production Problem Possible Cause Remedy Problem Possible Cause Remedy Evaporator is Frozen Up Problem Possible Cause Remedy Low Ice Production Abnormal Ice Other Service for Refrigerant Lines Removal and Replacement of ComponentsRefrigerant Recovery Evacuation and Recharge R-404A BrazingRemoval and Replacement of Compressor Removal and Replacement of Expansion Valve Page Removal and Replacement of Evaporator Removal and Replacement of Air-Cooled Condenser Removal and Replacement of Water-Cooled Condenser Removal and Replacement of Remote Air-Cooled Condenser Page Adjustment of Water Regulating Valve water-cooled model Removal and Replacement of Thermistor Removal and Replacement of Inlet Water Valve Removal and Replacement of Pump Motor Removal and Replacement of Control Board Cleaning and Sanitizing Instructions VI. Cleaning and MaintenanceCleaning Procedure Sanitizing Procedure Following Cleaning Procedure Preparing the Icemaker for Long Storage MaintenanceDrain the water tank