Hoshizaki KM-150BAF User manual

™
SERVICE MANUAL
ISSUED: FEB. 27, 1998
KM-150BAF
KM-150BWF
CRESCENT CUBER
Reliability is a
beautiful thing
TM
REVISED: DEC. 14, 2003
NUMBER: 73066

2
IMPORTANT
Only qualified service technicians should attempt to service or maintain this icemaker.
No such service or maintenance should be undertaken until the technician has
thoroughly read this Service Manual.
HOSHIZAKI AMERICA, INC.
618Highway74South
PeachtreeCity,GA 30269
Attn: HOSHIZAKITechnicalSupportDepartment
Phone: [phone]TechnicalService
[phone]
Fax: [phone]
NOTE: Toexpediteassistance,allcorrespondence/communicationMUST includethefollowing
information:
• ModelNumber
• SerialNumber
• Completeanddetailedexplanationoftheproblem
HOSHIZAKI provides this manual primarily to assist qualified service technicians in the
service and maintenance of the icemaker.
Should the reader have any questions or concerns which have not been satisfactorily
addressed, please call or write to the HOSHIZAKI Technical Support Department for
assistance.

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• Pleasereview thismanual. Itshouldbereadcarefullybeforetheicemakerisservicedor
maintenanceoperationsperformed.Onlyqualifiedservicetechniciansshouldserviceand
maintaintheicemaker. Thismanualshouldbemadeavailabletothetechnicianpriorto
serviceormaintenance.
CONTENTS
PAGE
I. SPECIFICATIONS .................................................................................................... 5
1. KM-150BAF (Air-cooled) ..................................................................................... 5
2. KM-150BWF (Water-cooled) ............................................................................... 6
II. GENERAL INFORMATION ...................................................................................... 7
1. CONSTRUCTION ............................................................................................... 7
[a] KM-150BAF................................................................................................... 7
[b] KM-150BWF.................................................................................................. 8
2. CONTROLLER BOARD...................................................................................... 9
[a] SOLID-STATE CONTROL ............................................................................ 9
[b] CONTROLLER BOARD................................................................................ 9
[c] SEQUENCE ................................................................................................ 16
[d] CONTROLS AND ADJUSTMENTS ........................................................... 18
[e] CHECKING THE CONTROLLER BOARD ................................................. 21
3. SWITCHES ....................................................................................................... 24
III. TECHNICAL INFORMATION ............................................................................... 25
1. WATER CIRCUIT AND REFRIGERANT CIRCUIT.......................................... 25
[a] KM-150BAF (Air-cooled) ............................................................................. 25
[b] KM-150BWF (Water-cooled) ....................................................................... 26
2. WIRING DIAGRAM ........................................................................................... 27
3. TIMING CHART ................................................................................................ 28
4. PERFORMANCE DATA ................................................................................... 30
[a] KM-150BAF (Air-cooled) ............................................................................. 30
[b] KM-150BWF (Water-cooled) ....................................................................... 31
IV. SERVICE DIAGNOSIS ........................................................................................ 32
1. NO ICE PRODUCTION..................................................................................... 32
2. EVAPORATOR IS FROZEN UP....................................................................... 35
3. LOW ICE PRODUCTION .................................................................................. 36
4. ABNORMAL ICE............................................................................................... 36
5. OTHERS ........................................................................................................... 36

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V. REMOVAL AND REPLACEMENT OF COMPONENTS..........................................37
1. SERVICE FOR REFRIGERANT LINES ..............................................................37
[a] REFRIGERANT RECOVERY........................................................................37
[b] EVACUATION AND RECHARGE .................................................................37
2. BRAZING .............................................................................................................38
3. REMOVAL AND REPLACEMENT OF COMPRESSOR......................................39
4. REMOVAL AND REPLACEMENT OF DRIER ....................................................40
5. REMOVAL AND REPLACEMENT OF EXPANSION VALVE..............................41
6. REMOVAL AND REPLACEMENT OF HOT GAS VALVE...................................42
7. REMOVAL AND REPLACEMENT OF EVAPORATOR ......................................43
8. REMOVAL AND REPLACEMENT OF WATER-REGULATING VALVE .................
- WATER-COOLED MODEL ONLY....................................................................44
9. ADJUSTMENT OF WATER-REGULATING VALVE ...............................................
- WATER-COOLED MODEL ONLY....................................................................45
10. REMOVAL AND REPLACEMENT OF THERMISTOR ........................................46
11. REMOVAL AND REPLACEMENT OF FAN MOTOR...............................................
- EXCEPT WATER-COOLED MODEL...............................................................47
12. REMOVAL AND REPLACEMENT OF WATER VALVE ......................................47
13. REMOVAL AND REPLACEMENT OF PUMP MOTOR........................................48
14. REMOVAL AND REPLACEMENT OF FLOAT SWITCH .....................................49
15. REMOVAL AND REPLACEMENT OF SPRAY TUBE.........................................49
VI. CLEANING AND MAINTENANCE INSTRUCTIONS .............................................50
1. PREPARING THE ICEMAKER FOR LONG STORAGE......................................50
2. CLEANING AND SANITIZING PROCEDURES ..................................................52
[a] CLEANING PROCEDURE ............................................................................52
[b] SANITIZING PROCEDURE...........................................................................54
3. MAINTENANCE...................................................................................................55

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I. SPECIFICATIONS
1. KM-150BAF

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2. KM-150BWF

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II. GENERAL INFORMATION
1. CONSTRUCTION
[a] KM-150BAF

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[b] KM-150BWF

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2. CONTROLLER BOARD
[a] SOLID-STATE CONTROL
1) A HOSHIZAKI exclusive solid-state control is employed in KM-150BAF and
KM-150BWF Crescent Cubers.
2) A Printed Circuit Board (hereafter called “Controller Board”) includes a stable and
high quality control system.
3) All models are pretested and factory-adjusted.
[b] CONTROLLER BOARD
CAUTION
1. Fragile, handle very carefully.
2. A controller board contains integrated circuits, which are susceptible to
failure due to static discharge. It is especially important to touch the
metal part of the unit when handling or replacing the board.
3. Do not touch the electronic devices on the board or the back of the board
to prevent damage to the board.
4. Do not change wiring and connections. Especially, never misconnect
K3, K4 and K5, because the same connector is used for the Thermistor
and Float Switch. K4 is not connected.
5. Do not fix the electronic devices or parts on the board in the field.
Always replace the whole board assembly when it goes bad.
6. Do not short out power supply to test for voltage.

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KM-150B_F models use either the Alpine Controller Board (orange):
PART NUMBER TYPE
2U0127-01 MY9KM910 (Alpine)
MY9KM91B (Alpine)
OR the Control Products Board (green):
PART NUMBER TYPE
2A0836-01 HOSHIZAKI 001 (Control Products - 8 Pin)
OR the Control Products Improved “E” Board (green):
PART NUMBER TYPE
2A1410-01 HOS-001A (Control Products - 10 Pin)
Features of All Three Controller Boards
(1) Maximum Water Supply Period - 6 minutes
Water Solenoid Valve opening, in the Defrost (Harvest) Cycle, is limited by
maximum period of the defrost timer. The Water Valve cannot remain open
longer than the maximum period. The Water Valve can close in less than the
maximum period if the defrost cycle is completed.
(2) Defrost Timer
The defrost cycle starts when the Float Switch opens and completes the
freeze cycle. But the Defrost Timer does not start counting until the Thermistor
senses 48°F at the Evaporator outlet. The period from the end of the freeze
cycle up to the point of the Thermistor's sensing varies depending on the
ambient and water temperatures.
(3) High Temperature Safety - 127 ± 7°F
The temperature of the suction line in the refrigerant circuit is limited by the
High Temperature Safety.
During the defrost cycle the Evaporator temperature rises. The Thermistor
senses 48°F and starts the Defrost Timer. After the Defrost Timer counts
down to zero, the normal freeze cycle begins. If the Evaporator temperature
continues to rise, the Thermistor will sense the rise in temperature and at 127
± 7°F the Thermistor operates the High Temperature Safety.

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This High Temperature Safety shuts down the circuit and the icemaker automatically
stops. To reset the safety, turn the power off and back on again.
This High Temperature Safety protects the unit from excessive temperature.
(4) Low Water Safety
If the Pump Motor is operated without water, the mechanical seal can fail. To
prevent this type of failure, the Controller Board checks the position of the Float
Switch at the end of the initial one minute water fill cycle and at the end of each
defrostcycle.
If the Float Switch is in the up position (electrical circuit closed), the Controller
Board changes to the ice making cycle. If the Float Switch is in the down position
(electrical circuit open), the Controller Board changes to a one minute water fill
cycle before starting the ice making cycle. This method allows for a Low Water
Safety shut down to protect the Water Pump from mechanical seal failure.
For water-cooled model, if the water is shut off, the unit is protected by the High
Pressure Switch.
(5) High Voltage Cut-out
The maximum allowable supply voltage of this icemaker is limited by the High
Voltage Cut-out.
If miswiring causes excessive voltage on the Controller Board, the High Voltage
Cut-out shuts down the circuit in 3 seconds and the icemaker automatically stops.
When the proper supply voltage is resumed, the icemaker automatically starts
running again.

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Connector K1
Pins #1 through #10
#1, 9 Magnetic Contactor
#2 Hot Gas Valve
#3 Line Valve
#4 Pump Motor (icemaking)
#5 Pump Motor (drain)
#6 Water Valve
#7, 10 Power (line, Bin Control)
#8 Open
Dip Switch
Defrost Timer, Drain Timer
& Drain Counter
Connector K5
Float Switch
Connector K4
Open
(not connected)
Connector K3
Defrost Control
(Thermistor)
(Alpine “C”/Alpine Board)

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Features of Control Products “E” Controller Board
The “E” board includes LED lights and audible alarm safeties. The red LED indicates proper control
voltage and will remain on unless a control voltage problem occurs. At startup a 5 second delay
occurs while the board conducts an internal timer check. A short beep occurs when the power
switch is turned ON or OFF.
Thegreen LED’s1-4 representthe correspondingrelaysand energizeandsequence 5secondsfrom
initial startup as follows:
SequenceStep LED’son Length: Min. Max. Avg.
1 Minute Fill Cycle LED4 60 sec.
HarvestCycle LED1, 4, & 2 2 min. 20 min. 3-5min.
Freeze Cycle LED1 5 min. 60 min. 30-35min.
Reverse Pump Out LED1, 3, & 2 10 sec. 20 sec. Factory set.
{LED 1 – Comp; LED 2 - HGV/CFM; LED 3 – PM; LED 4 - WV}
The built in safeties shut down the unit and have alarms as follows:
1 beep every 3 sec. = High Evaporator Temperature >127 ° F.
Check for defrost problem (stuck HGV or relay), hot water entering unit, stuck headmaster or shorted
thermistor.
2 beeps every 3 sec. = Defrost Back Up Timer. Defrost >20 minutes.
OrangeLEDmarked20MINenergizes.
Check for open thermistor, HGV not opening, TXV leaking by, low charge or inefficient compressor.
3 beeps every 3 sec. = Freeze Back Up Timer. Freeze > 60 minutes.
YellowLEDmarked 60 MINenergizes.
Check for F/S stuck closed (up), WV leaking by, HGV leaking by, TXV not feeding properly, low
chargeorinefficientcompressor.
To manually reset the above safeties, depress white alarm reset button with the power supply ON.
6 beeps every 3 sec. = Low Voltage. Voltage is 92 Vac or less.
7 beeps every 3 sec. = High Voltage. Control voltage > 147Vac ±5%.
Thered LEDwillde-energize ifvoltage protectionoperates.
The voltage safety automatically resets when voltage is corrected.
The Output Test switch “S3” provides a relay sequence test. With power OFF, place S3 ON and
switch power to ICE. The correct lighting sequence should be none, 2, 3, 4, 1, & 4, normal sequence
every 5 seconds. S3 should remain in the “OFF” position for normal operation.
The application switch located between relay X3 & X4 must be set to match the original board
application. Place this switch in the ALP position if there is no white wire supplied to the K1
connector. If there is a white wire, place the switch in the C position. If this switch is placed in
the wrong position either the compressor contactor will remain energized with the control switch
OFF or the unit will not start.
The dip switches should be adjusted per the adjustment chart published in the Tech Specs book. 7 &
8 must remain in the OFF position.

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(Control Products HOSHIZAKI001 Board)

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(Control Products HOS-001A Board)

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[c] SEQUENCE
1st Cycle
1. Unit energized and Control Switch to “ICE”
position. Water supply cycle starts.
IMPORTANT
Water Valve
opening is limited
to 6 minutes.
5. After the first 5 minutes in freeze cycle.
Ready to complete freeze cycle when Float
Switch circuit opens.
4. Defrost Timer stops counting.
Defrost cycle is completed and freeze cycle
starts.
IMPORTANT
Board never accepts freeze completion signal
within the first 5 minutes in freeze cycle.
IMPORTANT
1. Board never accepts defrost completion
signal within the first 2 minutes in defrost
cycle.
2. Defrost cycle time is limited to 20 minutes
even if Defrost Timer does not stop counting.
3. Thermistor reads 48° F (9°C).
Defrost Timer, adjustable from
1 to 3 minutes, starts counting.
2. After 1 minute,
Defrost cycle starts.

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IMPORTANT
Freeze cycle time is limited to 60 minutes
even if Float Switch does not open.
2nd Cycle and after with no pump drain
IMPORTANT
Water Valve
opening is limited to 6
minutes.
4. After the first 5 minutes in freeze cycle.
Ready to complete freeze cycle when Float
Switch circuit opens.
3. Defrost Timer stops counting.
Defrost cycle is completed and freeze cycle
starts.
IMPORTANT
Board never accepts freeze completion signal
within the first 5 minutes in freeze cycle.
IMPORTANT
1. Board never accepts defrost completion
signal within the first 2 minutes in defrost
cycle.
2. Defrost cycle time is limited to 20 minutes
even if Defrost Timer does not stop counting.
2. Thermistor reads 48° F (9°C).
Defrost Timer, adjustable from
1 to 3 minutes, starts counting.
1. Float Switch opens and signals to complete
freeze cycle. 10/20 second Drain Timer starts
counting.

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[d] CONTROLS AND ADJUSTMENTS
The Dip Switch is factory-adjusted to the following positions:
Switch Nos. 1 and 2:
Used for adjustment of the Defrost Timer.
TheDefrostTimerstarts counting whentheThermistorreads a certaintemperature
at the Evaporator outlet.
Switch Nos. 3 and 4:
Used for adjustment of the Drain Timer.
When a freeze cycle is completed, the Pump Motor stops, and the icemaker
resumes operation in 2 seconds. Then the Pump Motor drains the Water Tank
for the time determined by the Drain Timer. The Drain Timer also determines the
time to restrain completion of a defrost cycle, i.e. the minimum defrost time.
Switch Nos. 5 and 6:
Used for adjustment of the Drain Counter.
The Pump Motor drains the Water Tank at the frequency determined by the Drain
Counter.
Switch Nos. 7 and 8:
Used only for checking the Controller Board. Usually set in OFF position.
Switch Nos. 9 and 10:
Used for adjustment of Freeze Timer.
The Freeze Timer determines maximum
freeze cycle time. Upon termination of
Freeze Timer, machine initiates the
harvest cycle. After 2 consecutive timer
terminations, machine will shut down,
possibly indicating a problem.
DIP SWITCH NO. 1 2 3 45678910
2U0127-01 (BAF, BWF) OFF ON OFF ON OFF OFF OFF OFF NA NA
2A0836-01 (BAF, BWF) OFF ON OFF ON OFF OFF OFF OFF NA NA
2A1410-01 (BAF) OFF ON OFF ON OFF OFF OFF OFF OFF OFF
2A1410-01 (BWF) OFF ON OFF ON OFF OFF OFF OFF OFF ON

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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 (kΩ)
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. 10. 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 kΩ. 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 a 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

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3) Drain Timer
The Drain Timer is factory-adjusted, and no adjustment is required.
SETTING TIME
Dip Switch Dip Switch
No. 3 No. 4 T1 T2
OFF OFF 10 seconds 150 seconds
ON OFF 10 seconds 180 seconds
OFF ON 10 seconds 120 seconds
ON ON 20 seconds 180 seconds
T1: Time to drain the Water Tank
T2: Time to restrain defrost completion
4) Freeze Timer CAUTION
Adjust to proper specification, or the unit may not operate correctly.
Two new dip switches numbered 9 and 10 have been added to the improved “E” board to
better prevent possible freeze ups. These settings come factory set to the default setting
of 60 min. (OFF, OFF). Check the adjustment chart published in the Tech Specs for
proper settings. If the old board does not have these two dip switches, (only 8 instead of
10), leave setting as OFF, OFF.
SETTING TIME
Dip Switch Dip Switch
No. 9 No. 10
OFF OFF 60 min.
ON OFF 70 min.
OFF ON 50 min.
ON ON 60 min.