Hoshizaki KM-1300MAH, KM-1300MWH, KM-1300MRH Evaporator is Frozen UP, LOW ICE Production

Page 40

2. EVAPORATOR IS FROZEN UP

PROBLEM

POSSIBLE CAUSE

 

REMEDY

[1] Freeze cycle

a) Float Switch

1.

Leads short-circuit or

1.

Check and replace.

time is too

 

 

 

defective switch.

 

 

 

 

long.

 

 

2.

Float does not move freely.

2.

Clean or replace.

 

b) Water Solenoid

1.

Diaphragm does not close.

1.

Check for water leaks

 

Valve

 

 

 

with icemaker off.

 

 

 

 

 

 

 

 

 

 

c) Controller Board

1.

Defective.

1.

See “II.2[e] CHECKING

 

 

 

 

 

 

CONTROLLER BOARD.”

[2] All ice formed

a) Evaporator

1.

Scaled up.

1.

Clean.

 

 

on Evaporator

b) Water Supply Line

1.

Water pressure too low.

1.

Check and get

does not fall

 

 

 

 

 

recommended pressure.

into bin inc)

Water Solenoid

1.

Dirty mesh filter or orifice.

1.

Clean.

harvest cycle.

Valve

2.

Diaphragm does not close.

2.

Check for water leaks

 

 

 

 

 

 

with icemaker off.

 

d) Ambient and/or

1.

Too cool.

1. Increase temperature.

 

water temperature

 

 

 

 

 

 

 

e) Line Valve

1.

Continues to open in

1.

Check operation in

 

 

 

 

harvest cycle.

 

harvest cycle and replace.

 

f) Thermistor

1.

Out of position or loose

1.

See “V. 11. REMOVAL

 

 

 

 

attachment.

 

AND REPLACEMENT OF

 

 

 

 

 

 

THERMISTOR.”

 

g) Controller Board

1.

Defrost Timer is set too

1.

Adjust longer, referring

 

 

 

 

 

short.

 

to “II. 2. [d] CONTROLS

 

 

 

 

 

 

AND ADJUSTMENT, 2)

 

 

 

 

 

 

Defrost Timer.”

 

 

 

 

 

 

 

 

 

 

2. Defective.

2.

See “II. 2.[e] CHECKING

 

 

 

 

 

 

CONTROLLER BOARD.”

[3] Others

a) Spray Tubes

1. Clogged.

1. Clean.

 

 

 

2.

Out of position.

2.

Place in position.

 

 

b) Water System

1.

Dirty.

1.

Clean.

 

c) Refrigerant

1. Undercharged.

1.

Check for leaks and

 

 

 

 

 

 

recharge.

 

d) Expansion Valve

1.

Bulb out of position or

1.

Place in position.

 

 

 

 

loose attachment.

 

 

 

 

 

 

 

2. Defective.

2.

Replace.

 

e) Hot Gas Solenoid

1. Coil winding opened.

1. Replace.

 

Valve

 

2.

Plunger does not move.

2. Replace.

 

 

 

3.

Wiring to Hot Gas Valve.

3.

Check for loose

 

 

 

 

 

 

connection or open, and

 

 

 

 

 

 

replace.

 

 

 

 

 

 

 

 

 

3. LOW ICE PRODUCTION

PROBLEM

POSSIBLE CAUSE

REMEDY

 

 

 

[1] Freeze cycle

a) See chart 1 - [3], and check dirty Air Filter or Condenser, ambient or water

time is long.

temperature, water pressure, Water Regulator or refrigerant charge.

 

b) See chart 2 - [1], and check Float Switch, Water Solenoid Valve or Controller

 

Board.

 

[2] Harvest cycle

a) See chart 2 - [2], and check Controller Board, Thermistor, Evaporator, ambient

time is long

and/or water temperature, water supply line, Water Solenoid Valve orLine Valve.

 

.

 

 

 

 

40

Image 40
Contents KM-1300MAH KM-1300MWH KM-1300MRH Hoshizaki AMERICA, INC Contents Maintenance Specifications KM-1300MAH Air-cooled2a. KM-1300MWH Water-cooled 2b. KM-1300MWH Water-cooled Serial No. M10156D KM-1300MRH Remote air-cooled Condensing Unit URC-12F Specifications Model URC-12F II. General Information Construction KM-1300MWH Water-cooled KM-1300MRH Remote air-cooled Features of Control Products E Controller Board Controller BoardSOLID-STATE Control Controller BoardPage Beep every 3 sec. = High Evaporator Temperature 127 F Minute Fill CycleHarvest Cycle Freeze CycleControl Products HOS-001A Board Sequence 1st Cycle 2nd Cycle and after with pump drain 2nd Cycle and after with no pump drain Controls and Adjustments Setting Time Setting Frequency Checking the Controller Board Page III. Technical Information KM-1300MWH Water-cooled KM-1300MRH Remote air-cooled Wiring Diagrams KM-1300MAH Air-cooled and KM-1300MWH Water-cooledCut-out 412 ±21.3 Psig Cut-in 327±21.3 Psig Timing Chart Page Performance Data Serial # L00001F to M10155C KM-1300MWH Water-cooled Serial # M10156D KM-1300MRH Remote air-cooled IV. Service Diagnosis No ICE Production Problem Possible Cause RemedyController Board Problem Possible Cause Remedy Evaporator is Frozen UP LOW ICE ProductionAbnormal ICE OthersRefrigerant Recovery Service for Refrigerant LinesEvacuation and Recharge R-404A Brazing 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 Page Page Removal and Replacement of Thermistor Important Removal and Replacement of FAN Motor Removal and Replacement of Water Valve Removal and Replacement of Pump MotorRemoval and Replacement of Spray Tubes VI. Maintenance and Cleaning Instructions Preparing the Icemaker for Long StoragePage Cleaning Cleaning Procedure Sanitizing Procedure Following Cleaning Procedure Page Maintenance