Hoshizaki KM-2400SRF3, KM-2400SRH3 service manual Setting Time

Page 18

1) Defrost Control

A thermistor (Semiconductor) is used for a defrost control sensor. The resistance varies depending on the Suction Line temperatures. The Thermistor detects the temperature of the Evaporator outlet to start the Defrost Timer. No adjustment is required. If necessary, check for resistance between Thermistor leads, and visually check the Thermistor mounting, located on the Suction Line next to the Evaporator outlet.

Temperature (°F)

Resistance (k)

0

14.401

10

10.613

32

6.000

50

3.871

70

2.474

90

1.633

Check a thermistor for resistance by using the following procedures.

(i)Disconnect the connector K3 on the board.

(ii)Remove the Thermistor. See “V. 11. REMOVAL AND REPLACEMENT OF THERMISTOR.”

(iii)Immerse the Thermistor sensor portion in a glass containing ice and water for 2 or 3 minutes.

(iv)Check for a resistance between Thermistor leads.

Normal reading is within 3.5 to 7 k. Replace the Thermistor if it exceeds the normal reading.

2)Defrost Timer

No adjustment is required under normal use, as the Defrost Timer is adjusted to the suitable position. However, if necessary when all the ice formed on the Evaporator does not fall into the bin in the harvest cycle, adjust the Defrost Timer to longer setting by adjusting the Dip Switch (No. 1 & 2) on the Controller Board.

SETTING

 

TIME

Dip Switch

Dip Switch

 

No. 1

 

No. 2

 

OFF

 

OFF

60 seconds

ON

 

OFF

90 seconds

OFF

 

ON

120 seconds

ON

 

ON

180 seconds

18

Image 18
Contents Stackable Crescent Cuber Hoshizaki AMERICA, INC Contents Maintenance Specifications Condensing UNIT, URC-24F Specifications Model URC-24F II. General Information Construction SOLID-STATE Control Features of Control Products E Controller BoardController Board Controller BoardPage Harvest Cycle Beep every 3 sec. = High Evaporator Temperature 127 FMinute Fill Cycle Freeze CycleControl Products HOSHIZAKI001 Board Control Products HOS-001A Board Sequence 1st Cycle 2nd Cycle and after with pump drain Important Water Valve opening is limited to 6 minutes2nd Cycle and after with no pump drain Controls and Adjustments OFFSetting Time Setting Frequency Checking the Controller Board Page III. Technical Information Wiring Diagram Timing Chart Page Performance Data IV. Service Diagnosis No ICE Production Problem Possible Cause RemedyController Board Problem Possible Cause Remedy Evaporator is Frozen UP ThermistorLOW ICE Production Abnormal ICEOthers Refrigerant Recovery Removal and Replacement of ComponentsService for Refrigerant Lines Evacuation and Recharge R-404ABrazing Removal and Replacement of Compressor Important Removal and Replacement of Drier Removal and Replacement of Expansion Valve Removal and Replacement of HOT GAS Valve and Line Valve Removal and Replacement of Evaporator Important Page Removal and Replacement of Thermistor Caution Removal and Replacement of FAN Motor Removal and Replacement of Water Valve Removal and Replacement of Pump MotorRemoval and Replacement of Spray Tubes VI. Cleaning and Maintenance Instructions Important Preparing the Icemaker for Long StoragePage Cleaning Procedure Cleaning Procedure Page Sanitizing Procedure Following Cleaning Procedure Maintenance