Hoshizaki KM-500MAH User manual

™
SERVICE MANUAL
ISSUED: NOV. 7, 2002
KM-500MAH
KM-500MWH
KM-500MRH
MODULAR CRESCENT CUBER
Reliability is a
beautiful thing
TM
REVISED: DEC. 16, 2003
NUMBER: 73104

2
IMPORTANT
Only qualified service technicians should attempt to service or maintain this icemaker.
No 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.

3
• Please review this manual. It should be read carefully before the icemaker is serviced
or maintenance operations performed. Only qualified service technicians should service
and maintain the icemaker. This manual should be made available to the technician
prior to service or maintenance.
CONTENTS PAGE
I.SPECIFICATIONS...................................................................................................... 5
1. KM-500MAH (Air-cooled)..................................................................................... 5
2a. KM-500MWH (Water-cooled) Serial #L00001D - M20960C .............................. 6
2b. KM-500MWH Serial #M30961D ........................................................................ 7
3. KM-500MRH(Remote air-cooled)........................................................................ 8
4. CONDENSERUNIT,URC-6F.............................................................................. 9
II.GENERALINFORMATION ...................................................................................... 11
1. CONSTRUCTION............................................................................................... 11
[a]KM-500MAH(Air-cooled)............................................................................. 11
[b]KM-500MWH(Water-cooled)....................................................................... 12
[c]KM-500MRH(Remoteair-cooled) ................................................................ 13
2. CONTROLLERBOARD..................................................................................... 14
[a]SOLID-STATECONTROL ........................................................................... 14
[b]CONTROLLERBOARD............................................................................... 14
[c]SEQUENCE ................................................................................................ 18
[d]CONTROLSANDADJUSTMENTS ............................................................. 20
[e]CHECKINGCONTROLLERBOARD ........................................................... 24
3. MECHANICALBINCONTROL........................................................................... 26
[a] PROXIMITYSWITCH ................................................................................... 26
[b] EXPLANATIONOF OPERATION................................................................ 26
[c] TROUBLESHOOTING ................................................................................. 27
III. TECHNICALINFORMATION .................................................................................. 28
1. WATERCIRCUITANDREFRIGERANTCIRCUIT .............................................. 28
[a]KM-500MAH ................................................................................................ 28
[b]KM-500MWH ............................................................................................... 29
[c]KM-500MRH ................................................................................................ 30
2. WIRINGDIAGRAMS .......................................................................................... 31
[a]KM-500MAHandKM-500MWH ................................................................... 31
[b]KM-500MRH ................................................................................................ 33
3. TIMINGCHART.................................................................................................. 35
4. PERFORMANCE DATA .................................................................................... 37
[a]KM-500MAH ................................................................................................ 37
[b] KM-500MWHSerial #L00001D - M20960C.................................................. 38
[c] KM-500MWH Serial #M30961D .................................................................. 39
[d]KM-500MRH ................................................................................................ 40

4
IV. SERVICE DIAGNOSIS...........................................................................................41
1. NOICE PRODUCTION.........................................................................................41
2. EVAPORATOR IS FROZEN UP ..........................................................................42
3. LOW ICE PRODUCTION......................................................................................42
4. ABNORMAL ICE ..................................................................................................45
5. OTHERS ..............................................................................................................45
V. REMOVALAND REPLACEMENT OFCOMPONENTS............................................46
1. SERVICE FOR REFRIGERANT LINES ..............................................................46
[a] REFRIGERANT RECOVERY........................................................................46
[b] EVACUATION AND RECHARGE..................................................................46
2. BRAZING.............................................................................................................47
3. REMOVAL AND REPLACEMENT OF COMPRESSOR .......................................48
4. REMOVAL AND REPLACEMENT OF DRIER .....................................................50
5. REMOVAL AND REPLACEMENT OF EXPANSION VALVE ...............................50
6. REMOVAL AND REPLACEMENT OF HOT GAS VALVE AND ...............................
LINE VALVE........................................................................................................51
7. REMOVAL AND REPLACEMENT OF EVAPORATOR ........................................52
8. REMOVAL AND REPLACEMENT OF WATER-REGULATING VALVE ..................
- WATER COOLED MODEL ONLY.....................................................................54
9. ADJUSTMENT OF WATER-REGULATING VALVE ................................................
- WATER COOLED MODEL ONLY.....................................................................55
10. REMOVAL AND REPLACEMENT OF CONDENSING PRESSURE ........................
REGULATOR (C.P.R.) - REMOTE AIR-COOLED MODEL ONLY .......................56
11. REMOVAL AND REPLACEMENT OF THERMISTOR..........................................57
12. REMOVAL AND REPLACEMENT OF FAN MOTOR ............................................58
13. REMOVAL AND REPLACEMENT OF WATER VALVE........................................59
14. REMOVAL AND REPLACEMENT OF PUMP MOTOR .........................................59
15. REMOVAL AND REPLACEMENT OF SPRAY TUBES ........................................60
VI. CLEANING AND MAINTENANCE INSTRUCTIONS ...............................................61
1. PREPARING THE ICEMAKER FOR LONG STORAGE ......................................61
2. CLEANING AND SANITIZING PROCEDURES...................................................63
[a] CLEANING PROCEDURE .............................................................................64
[b] SANITIZING PROCEDURE ...........................................................................66
3. MAINTENANCE....................................................................................................67

5
I. SPECIFICATIONS
1. KM-500MAH
Note: We reserve the right to make changes in specifications and design without prior notice.
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 13 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *499 (226) 468 (212) 428 (194)
Reference without *marks 80 475 (216) 427 (194) 389 (176)
90 468 (212) *393 (178) 353 (160)
100 461 (209) 384 (174) 317 (144)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 9.5 lbs. ( 4.3 kg ) 480 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 1212 (7.4) 1164 (5.6)
WATER gal./24HR (gal./100 lbs.) 113 (28.8) 250 (50.1)
EXTERIOR DIMENSIONS (WxDxH) 22" x 27-3/8" x 30-5/6" (560 x 695 x 770 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 151 lbs. ( 69 kg ), Shipping 175 lbs. (80 kg)
CONNECTIONS - ELECTRIC Permanent - Connection
- WATER SUPPLY Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL N/A
BIN CONTROL SYSTEM Proximity Switch with Delay
COMPRESSOR Hermetic, Model AKA9455ZXA
CONDENSER Air-cooled, Fin and tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R-404A, 1 lb. 10 oz. ( 735 g )
DESIGN PRESSURE High 467 PSIG, Low 230 PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A
-REQUIRED Ice Storage Bin
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V
AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG
3/8" OD Pipe

6
2a. KM-500MWH Serial #L00001D - M20960C
Note: We reserve the right to make changes in specifications and design without prior notice.
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 10 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *463 (210) 448 (203) 423 (192)
Reference without *marks 80 451 (205) 428 (194) 401 (180)
90 448 (203) *411 (186) 385 (175)
100 442 (200) 405 (184) 361 (164)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 9.5 lbs. ( 4.3 kg ) 480 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 1130 (6.6) 1100 (5.7)
WATER gal./24HR (gal./100 lbs.) 135 (32) 245 (52.8)
WATER COOLED CONDENSER 723 (176) 380 (82)
gal./24HR (gal./100 lbs.)
EXTERIOR DIMENSIONS (WxDxH) 22" x 27-3/8" x 30-5/16" (560 x 695 x 770 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 146 lbs. ( 66 kg ), Shipping 170 lbs. (77 kg.)
CONNECTIONS - ELECTRIC Permanent - Connection
- WATER SUPPLY Inlet 1/2" FPT Condenser Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT Condenser Outlet 3/8" FPT
3/8" OD Pipe
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL Pressure Regulator
BIN CONTROL SYSTEM Proximity Switch with Delay
COMPRESSOR Hermetic, Model AKA9455ZXA
CONDENSER Water-cooled, Tube in tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R-404A, 13.2 oz. ( 375 g )
DESIGN PRESSURE High 427 PSIG, Low 230 PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A
-REQUIRED Ice Storage Bin
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V
AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG

7
2b. KM-500MWH Serial #M30961D -
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 10 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *480 (218) 471 (213) 439 (199)
Reference without *marks 80 473 (214) 458 (208) 417 (189)
90 471 (213) *448 (203) 410 (186)
100 458 (208) 439 (199) 375 (170)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 9.5 lbs. (4.3 kg) 480 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 1157 (6.2) 1140 (5.7)
WATER gal./24HR (gal./100 lbs.) 133 (29.7) 268 (55.8)
WATER COOLED CONDENSER 699 (156) 394 (82)
gal./24HR (gal./100 lbs.)
EXTERIOR DIMENSIONS (WxDxH) 22" x 27-3/8" x 30-5/16" (560 x 695 x 770 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 146 lbs. ( 66 kg ), Shipping 170 lbs. ( 77 kg )
CONNECTIONS - ELECTRIC Permanent - Connection
- WATER SUPPLY Inlet 1/2" FPT Condenser Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT Condenser Outlet 3/8" FPT
3/8" OD Pipe
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL Pressure Regulator
BIN CONTROL SYSTEM Proximity Switch with Delay
COMPRESSOR Hermetic, Model AKA9455ZXA
CONDENSER Water-cooled, Tube in tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R-404A, 15 oz. ( 425 g )
DESIGN PRESSURE High 427 PSIG, Low 206 PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A
-REQUIRED Ice Storage Bin
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V
AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG

8
3. KM-500MRH
Note: We reserve the right to make changes in specifications and design without prior notice.
AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 15 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *517 235) 493 (224) 449 (204)
Reference without *marks 80 499(226) 462 (210) 411 (187)
90 493 (224) *436 (198) 387 (176)
100 480 (218) 425 (193) 342 (155)
SHAPE OF ICE Crescent Cube 480
ICE PRODUCTION PER CYCLE 9.5 lbs. (4.3 kg ) 480 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 1272 (7.0) 1206 (5.6)
WATER gal./24HR (gal./100 lbs.) 137 (31.3) 233 (45.1)
EXTERIOR DIMENSIONS (WxDxH) 22" x 27-3/8" x 30-5/16" (560 x 695 x 770 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 151 lbs. ( 69 kg ), Shipping 175 lbs. ( 80 kg )
CONNECTIONS - ELECTRIC Permanent - Connection
- WATER SUPPLY Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT
3/8" OD Pipe
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL N/A
BIN CONTROL SYSTEM Proximity Switch with Delay
COMPRESSOR Hermetic, Model AKA9455ZXA
CONDENSER Air-cooled Remote, Condenser Unit URC 6F
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
Condensing Pressure Regulator on URC-6F
REFRIGERANT CHARGE R-404A, 4 lbs. 0 oz. ( 1800 g )
( Icemaker 2 lbs. 1.5 oz. Cond. Unit 1 lb. 14 oz. )
DESIGN PRESSURE High 467 PSIG, Low 230 PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A
-REQUIRED Ice Storage Bin, Remote Condenser Unit
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V
AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG

9
4. CONDENSER UNIT
URC-6F 24"
(610 mm.)
23-1/32"
(585 mm.)
19-11/16"
(500 mm.)
18-1/8"
(460 mm.)
20-15/32"
(520 mm.)
21-15/16"
(557 mm.)
7/8" DIA. HOLE
(23 mm. DIA.)
6-5/16"
(160 mm.)
2-15/16"
(75 mm.)
18-1/8"
(460 mm.)
6/16" x 3/4" (10 mm. x 20 mm.)
4 x 2 (SLOTTED HOLES)
17-1/8"
(435 mm.)
14-9/16"
(370 mm.)
14-1/8"
(358 mm.)
14-15/16"
(380 mm.)
15-11/16"
(398 mm.)
17-7/8"
(454 mm.)
2-1/2"
(63 mm.)
14-15/16"
(380 mm.)

10
Galvanized Steel
21-15/16" x 15-11/16" x 17-7/8"
(557 x 398 x 453.8 mm.)
R404A 1 lb. 2 oz. (505 g)
Net 61 lbs. (28 kg)
Shipping 68 lbs. (31 kg)
One Shot Couplings (Aeroquip)
PermanentConnection
Air-cooled
Condensing Pressure Regulator
Min. -20°F - Max. +122°F
(-29°C to +50°C)
Outdoor use
SPECIFICATIONS
EXTERIOR
DIMENSIONS (W x D x H)
REFRIGERANT CHARGE
WEIGHT
CONNECTIONS
REFRIGERANT
ELECTRICAL
CONDENSER
HEAD PRESSURE CONTROL
AMBIENT CONDITION
MODEL: URC-6F

11
II. GENERAL INFORMATION
1. CONSTRUCTION
[a] KM-500MAH
Spray Tubes Water Supply Inlet
Control Switch
Condenser
Hot Gas Valve
Expansion Valve Fan Motor
Condenser
Compressor Drier
Float Switch Control Box
Water Pump
Bin Control Thermostat
(exceptmodels with
MechanicalBinControl)
Mechanical
Bin Control
(exceptmodels
withThermostat)

12
[b] KM-500MWH
Spray Tubes Water Supply Inlet
Control Switch Water Regulator
Expansion Valve Hot Gas Valve
Compressor
Float Switch Drier
Water Pump Control Box
Bin Control Thermostat
(exceptmodels with
MechanicalBinControl)
Mechanical
Bin Control
(exceptmodels
withThermostat)

13
[c] KM-500MRH
Spray Tubes Water Supply Inlet
Control Switch Junction Box
Expansion Valve Receiver Tank
Compressor
Float Switch Drier
Water Pump Hot Gas Valve
Line Valve
Control Box
Bin Control Thermostat
(exceptmodels with
MechanicalBinControl)
Mechanical
Bin Control
(exceptmodels
withThermostat)

14
2. CONTROLLER BOARD
[a] SOLID-STATE CONTROL
1) A HOSHIZAKI exclusive solid-state control is employed in Modular Crescent Cubers.
2) A Printed Circuit Board (hereafter called “Controller Board”) includes a stable and high
qualitycontrolsystem.
3) All models are pretested and factory-adjusted.
[b] CONTROLLER BOARD
CAUTION
1.Fragile,handleverycarefully.
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. Do not misconnect K3, K4 and K5,
because the same connector is used for the Thermistor (white), Float Switch
(black),andMechanical BinControl (red).
(For machines with thermostat, there is no connection on K4.)
5. Always replace the whole board assembly when it goes bad.
6. Do not short out power supply to test for voltage.
PART NUMBER TYPE
2A1410-01 HOS-001A (Control Products)
Features of Control Products “E” Controller Board
1)Maximum WaterSupply Period -6 minutes
Water Solenoid Valve opening, in the Defrost (Harvest) Cycle, is limited by the defrost
timer. The Water Valve cannot remain open longer than the
maximum period. The Water Valve can close in less than six minutes if the defrost cycle is
completed.

15
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.
This High Temperature Safety shuts down the circuit and the icemaker automatically
stops.
This High Temperature Safety protects the unit from excessive temperature. The Control
Board will Beep every 3 seconds. The white Reset Button on the Control Board must be
pressed with power on to reset the Safety.
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 defrost cycle.
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 Cutout
ThemaximumallowablesupplyvoltageofthisicemakerislimitedbytheHighVoltageCutout.
If miswiring (especially on single phase 3 wire models) causes excessive voltage on the
Controller Board, the High Voltage Cutout shuts down the circuit in 3 seconds and the
icemaker automatically stops. When the proper supply voltage is resumed, the icemaker
automaticallystarts runningagain. The Control Boardwill signal thisproblem using7Beeps
every3seconds.
6) 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.

16
The green LED’s 1-4 represent the corresponding relays and energize and sequence 5
seconds from initial start-up as follows:
Sequence Step LED’s on Length: Min. Max. Avg.
1 Minute Fill Cycle LED4 60 sec.
Harvest Cycle LED1, 4, & 2 2min. 20min. 3-5min.
Freeze Cycle LED1 5min. 60min. 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.
Orange LED marked 20 MIN energizes.
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.
Yellow LED marked 60 MIN energizes.
Check for F/S stuck closed (up), WV leaking by, HGV leaking by, TXV not feeding
properly, lowcharge, or inefficientcompressor.
To manually reset the above safeties, depress white alarm reset button with the power
supplyON.
6 beeps every 3 sec. = Low Voltage. Voltage is 92 Vac or less.
7 beeps every 3 sec. = High Voltage. Control voltage > 147 Vac ±5%.
The red LED will de-energize if voltage protection operates.
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.
Machines
with
mechanical
bin control
ONLY
4 beeps every 3 sec. = Short Circuit between the K4 connection on
the control board and the bin control relay. Check connections and
replacewire harness ifnecessary.
5 beeps every 3 sec. = Open Circuit between the K4 connection
on the control board and the bin control relay. Check connections and
replacewire harness ifnecessary.

17
(Control Products HOS-001A Board)
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 ener-
gized 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. Number 8 must remain in the OFF position.

18
[c] SEQUENCE
1st Cycle
1. Unit energized and Control Switch to “ICE”
position. Water supply cycle starts.
2. After 1 minute,
Defrost cycle starts.
3. Thermistor reads 48° F.
Defrost Timer starts counting.
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.

19
2nd Cycle and after with pump drain
IMPORTANT
Freeze cycle time is limited to 60 minutes even
if Float Switch does not open.
1. Float Switch opens and signals to complete
freeze cycle.
Drain timer starts counting.
2. Drain timer stops counting.
Pump drain is completed
3. Thermistor reads 48° F.
Defrost Timer starts
counting.
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.
&

20
IMPORTANT
Freeze cycle time is limited to 60 minutes even
if Float Switch does not open.
2nd Cycle and after with no pump drain
1. Float Switch opens and signals to complete
freeze cycle. 2. Thermistor reads 48° F.
Defrost Timer starts counting.
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.
&