Hoshizaki Serenity Series KMS-822MLH User manual

Hoshizaki
“A Superior Degree
of Reliability”
www.hoshizaki.com
Model
KMS-822MLH
Including
Condensing Unit Model SRK-10H
Modular Crescent Cuber
Serenity Series
Hoshizaki America, Inc.
SERVICE MANUAL
™
Number: 73182
Issued: 2-18-2011

2
IMPORTANT
Only qualied service technicians should install, service, and maintain the
icemaker. No service or maintenance should be undertaken until the technician
has thoroughly read this Service Manual. Failure to service and maintain
the equipment in accordance with this manual may adversely affect safety,
performance, component life, and warranty coverage.
Hoshizaki provides this manual primarily to assist qualied 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, write, or send an e-mail message to the Hoshizaki Technical
Support Department for assistance.
HOSHIZAKI AMERICA, INC.
618 Highway 74 South
Peachtree City, GA 30269
Attn: Hoshizaki Technical Support Department
Phone: [phone] Technical Support
[phone]
Fax: [phone]
[phone]
E-mail: [email protected]
Web Site: www.hoshizaki.com
NOTE: To expedite assistance, all correspondence/communication MUST include the
following information:
  •ModelNumber
  •SerialNumber
  •Completeanddetailedexplanationoftheproblem.

3
CONTENTS
Important Safety Information ................................................................................................. 5
I. Specications...................................................................................................................... 7
A. Icemaker ....................................................................................................................... 7
B. Condensing Unit............................................................................................................ 8
II. General Information ........................................................................................................... 9
A. Construction.................................................................................................................. 9
1. Icemaker .................................................................................................................. 9
2. Condensing Unit.................................................................................................... 10
B. Sequence of Operation ................................................................................................11
1. Sequence Cycles and Shutdown ............................................................................11
a) 1-Minute Fill Cycle .............................................................................................11
b) Initial Harvest Cycle .........................................................................................11
c) Freeze Cycle .....................................................................................................11
d) Pump-Out Cycle............................................................................................... 12
e) Harvest Cycle................................................................................................... 12
f) Shutdown.......................................................................................................... 12
2. Sequence Flow Chart............................................................................................ 13
C. Control Board .............................................................................................................. 14
1. Control Board Layout ............................................................................................. 15
2. LED Lights and Audible Alarm Safeties ................................................................. 16
3. Controls and Adjustments...................................................................................... 17
a) Default Dip Switch Settings.............................................................................. 17
b) Harvest Timer (S4 dip switch 1 & 2)................................................................. 17
c) Pump-Out Timer (S4 dip switch 3 & 4)............................................................. 18
d) Pump-Out Frequency Control (S4 dip switch 5 & 6)......................................... 18
e) Harvest Pump Timer (S4 dip switch 7)............................................................. 19
f) Factory Use (S4 dip switch 8) ........................................................................... 19
g) Freeze Timer (S4 dip switch 9 & 10) ................................................................ 19
h) Float Switch Control (S5 dip switch 1) ............................................................ 20
i) Rell Counter (S5 dip switch 2 through 5)......................................................... 20
D. Control Switch ............................................................................................................. 20
III. Technical Information ...................................................................................................... 21
A. Water Circuit and Refrigeration Circuit ........................................................................ 21
B. Wiring Diagram............................................................................................................ 22
C. Performance Data ....................................................................................................... 23
IMPORTANT
This manual should be read carefully before the icemaker is serviced or
maintenance operations are performed. Only qualied service technicians
should install, service, and maintain the icemaker. Read the warnings contained
in this booklet carefully as they give important information regarding safety.
Please retain this booklet for any further reference that may be necessary.

4
IV. Service Diagnosis.......................................................................................................... 24
A. Diagnostic Procedure ................................................................................................. 24
B. Control Board Check ................................................................................................... 27
C. Bin Control Check and Cleaning ................................................................................. 28
1. Bin Control Check .................................................................................................. 28
2. Bin Control Cleaning.............................................................................................. 30
D. Float Switch Check and Cleaning ............................................................................... 31
1. Float Switch Check ................................................................................................ 31
2. Float Switch Cleaning............................................................................................ 32
E. Thermistor Check........................................................................................................ 33
F. Diagnostic Charts ........................................................................................................ 34
1. No Ice Production................................................................................................... 34
2. Freeze-Up.............................................................................................................. 35
3. Low Ice Production ................................................................................................ 37
V. Replacement of Components .......................................................................................... 38
A. Service for Refrigerant Lines....................................................................................... 38
1. Refrigerant Recovery ............................................................................................. 38
2. Brazing .................................................................................................................. 39
3. Evacuation and Recharge (R-404A)...................................................................... 39
B. Important Notes for Component Replacement............................................................ 41
VI. Cleaning and Maintenance............................................................................................. 42
A. Cleaning and Sanitizing Instructions ........................................................................... 42
1. Cleaning Procedure................................................................................................ 43
2. Sanitizing Procedure - Following Cleaning Procedure ........................................... 45
B. Maintenance................................................................................................................ 46
C. Preparing the Icemaker for Long Storage ................................................................... 46

5
Important Safety Information
Throughout this manual, notices appear to bring your attention to situations which could
result in death, serious injury, or damage to the unit.
WARNING Indicates a hazardous situation which could result in death or
serious injury.
CAUTION Indicates a situation which could result in damage to the unit.
IMPORTANT Indicates important information about the use and care of the
unit.
WARNING
This icemaker should be destined only to the use for which it has been
expressly conceived. Any other use should be considered improper and
therefore dangerous. The manufacturer cannot be held responsible for injury or
damage resulting from improper, incorrect, and unreasonable use.
To reduce the risk of death, electric shock, serious injury, or re, follow
basic precautions including the following:
•Thisunitshouldbedisassembledorrepairedonlybyqualiedservice
personnel to reduce the risk of electric shock, injury, or re.
•Movethecontrolswitchtothe"OFF"positionandturnoffthepowersupply
to the SRK condensing unit before any servicing to the KMS or SRK is
undertaken. Place the KMS disconnect (if applicable) in the off position.
Lockout/Tagout to prevent the power supply from being turned back on
inadvertently.
•Donotmakeanyalterationstotheunit.Alterationscouldresultinelectric
shock, injury, re, or damage to the unit.
For KMS
•PowersupplyandgroundconnectionaresuppliedfromtheSRKremote
condensing unit via the wire harness provided. Do not connect the wire
harness leads to an external power source.
•Wireharnessrouting(conduit)anddisconnect(ifrequired)mustmeet
national, state, and local electrical code requirements. Failure to meet these
code requirements could result in death, electric shock, serious injury, re, or
severe damage to equipment.
•THE ICEMAKER MUST BE GROUNDED. Failure to properly ground
the icemaker could result in death, serious injury, or severe damage to
equipment.

6
For SRK
•Electricalconnectionmustbehard-wiredandmustmeetnational,state,and
local electrical code requirements. Failure to meet these code requirements
could result in death, electric shock, serious injury, re, or severe damage to
equipment.
•Theremotecondensingunitrequiresanindependentpowersupplyofproper
capacity. See the nameplate for electrical specications. Failure to use a
properly sized breaker or fuse can result in a tripped breaker, blown fuses, or
damage to existing wiring. This could lead to heat generation or re.
•THE REMOTE CONDENSING UNIT MUST BE GROUNDED. Failure to
properly ground the remote condensing unit could result in death or serious
injury.

7
I. Specications
A. Icemaker
1. KMS-822MLH
Note: We reserve the right to make changes in specications and design without prior
notice.
AC SUPPLY VOLTAGE 115VAC Supplied by SRK-10H via Factory Supplied
Wire Harness
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *839 (381) 820 (372) 769 (349)
Reference without *marks 80 824 (374) 795 (361) 730 (331)
90 820 (372) *774 (351) 714 (324)
100 801 (364) 760 (345) 659 (299)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 13.6 lb. (6.2 kg) 624 pcs.
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
KMS/SRK COMBINED ELECTRIC W (kWH/100 lbs.) 1800 (5.58) 1710 (4.89)
WATER gal./24HR (gal./100 lbs.) 149 (19.3) 363 (43.3)
EXTERIOR DIMENSIONS (W×D×H) 22"×24-5/8"×28" (559×625×713 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (rear)
WEIGHT Net 122 lb. (55 kg), Shipping 152 lb. (69 kg)
CONNECTIONS - ELECTRIC Wire Harness Connection from SRK to KMS
- WATER SUPPLY Inlet 1/2" FPT
- DRAIN Outlet 3/4" FPT
- CONDENSATION 5/8" OD Tube
- REFRIGERATION Liquid Line 1/2" Copper Tube Field Connection
Suction Line 5/8" Copper Tube Field Connection
CUBE CONTROL SYSTEM Float Switch
HARVEST CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled, Overflow Pipe, Float Switch
COOLING WATER CONTROL N/A
BIN CONTROL SYSTEM Mechanical Bin Control
COMPRESSOR In SRK
CONDENSING UNIT Air-Cooled Remote Condensing Unit SRK-10H
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
Headmaster (C.P.R.) in SRK-10H (160 PSI)
REFRIGERANT CHARGE 404A, 14 lb. 15.9 oz. (6800 g)
(Icemaker 0 lb. 7.1 oz. (200 g))
(Cond. Unit 14 lb. 8.8 oz. (6600 g))
DESIGN PRESSURE High 467 PSIG, Low 230 PSIG
CONTROL BOARD CIRCUIT PROTECTION High Voltage Cut-out (Internal)
REFRIGERATION CIRCUIT PROTECTION Auto-Reset High Pressure Switch in SRK-10H
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED Mechanical Bin Control Extension Bracket
-REQUIRED Dispenser Unit or Ice Storage Bin
SRK-10H Remote Condensing Unit
OPERATING CONDITIONS VOLTAGE RANGE 104-127VAC
AMBIENT TEMP. 45 -100°F
WATER SUPPLY TEMP. 45 - 90°F
WATER SUPPLY PRESSURE 10 - 113 PSIG
ENG.F-011.1.0205

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B. Condensing Unit
1. SRK-10H
Note: We reserve the right to make changes in specications and design without prior
notice.
AC SUPPLY VOLTAGE 208-230/60/1 (3 wire with neutral for 115VAC)
(115VAC Supplied to KMS via Factory Wire Harness)
AMPERAGE 11.5A (5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20A
MAXIMUM FUSE SIZE 20A
EXTERIOR DIMENSIONS (W×D×H) 50"×17"×28" (1270×432×711 mm)
DIMENSIONS INCLUDING LEGS (W×D×H) 52-3/8"×19-1/2"×43" (1330×495×1092 mm)
EXTERIOR FINISH Galvanized Steel
WEIGHT Net 230 lb. (104 kg) Shipping 273 lb. (124 kg)
CONNECTIONS - ELECTRIC Main Power Supply: Permanent Connection
SRK to KMS: Wire Harness Connection
- REFRIGERATION Liquid Line 1/2" Copper Tube Field Connection
Suction Line 5/8" Copper Tube Field Connection
COMPRESSOR Hermetic, Model CS10K6E-PFV-279
CONDENSER Air Cooled, Fin and Tube Type
COMPRESSOR PROTECTION Auto-Reset Overload Protector (Internal)
FAN MOTOR PROTECTION Thermal Protection
REFRIGERATION CIRCUIT PROTECTION Auto-Reset High Pressure Switch
Discharge Line Thermostat
REFRIGERANT CONTROL Headmaster (C.P.R.) (160 PSI)
REFRIGERANT CHARGE 404A, 14 lb. 15.9 oz. (6800 g)
(Condensing Unit 14 lb. 8.8 oz. (6600 g))
(Icemaker 0 lb. 7.1 oz. (200 g))
DESIGN PRESSURE High 467 PSIG, Low 230 PSIG
OPERATING CONDITIONS VOLTAGE RANGE 187-253VAC
AMBIENT TEMP. (Outdoor Use) -20-122°F
ACCESSORIES -SUPPLIED Leg 2 pcs
Hex Head Bolt w/Washer M8×16 16 pcs
Hex Nut M8 16 pcs
-REQUIRED Compatible KMS Icemaker
DRAWING NO. (DIMENSION) 3A6183
ENG.F-032.1.0205

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II. General Information
A. Construction
1. Icemaker
Spray Tube
Water Supply Inlet
Control Box
Drier
Hot Gas Valve (HGV)
Float Switch
Pump Motor
Bin Control
Control Switch
Expansion Valves (TXV)
Inlet Water
Valve
Cleaning Valve
Drain Valve
Spray Guide
High-Side Service Valve
Low-Side Service Valve
Liquid Line Valve (LLV)
Evaporator
Bin Control
Extension Bracket
Bin Control Cover
Insulation
Fuse (KMS)

10
2. Condensing Unit
Headmaster (CPR)
Control Box
Hot Gas
Valve (HGV)
Condenser Fan
Motors (FMR)
High-Side
Service Valve
Low-Side
Service Valve
Compressor
Condenser
Liquid Line
Valve (LLV)
Receiver
Accumulator
Discharge Thermostat
High-Pressure Switch
Fuse (SRK)

11
B. Sequence of Operation
1. Sequence Cycles and Shutdown
The steps in the sequence are as outlined below. When power is supplied, CB red
"POWEROK"LEDandgreen"BCCLOSED"LEDcomeon.Ifyellow"BCOPEN"LEDis
on, the unit will not start. In this case, clear ice away from the BC actuator paddle in the
dispenser unit/storage bin area. A 5-second delay occurs at startup. Note that the order
of the green sequence LEDs from the outer edge of CB is 1,4, 3, 2.
a) 1-Minute Fill Cycle
LED 4 is on. WV energizes and the 1-minute ll cycle begins. After 1 minute, CB checks
for a closed F/S. If F/S is closed, the harvest cycle begins. If not, WV remains energized
through additional 1-minute ll cycles until water lls the tank and closes F/S. This serves
as a low water safety to protect PM.
b) Initial Harvest Cycle
LEDs 1, 4, and 2 are on. WV remains energized, Comp, FMRs, and HGVs energize.
CBmonitors the warming of the evaporator via the thermistor located on the suction line.
When the thermistor reaches 48°F (9°C), CB reads a 3.9 kΩ signal from the thermistor
and turns harvest termination over to the adjustable harvest timer which is factory set for
normalconditions.Fordetails,see"II.C.3.b)HarvestTimer(S4dipswitch1&2)."WVis
energized during harvest for a maximum of 6 minutes or the length of harvest minus
50seconds (Harvest Pump Timer (S4 dip switch 7)), whichever is shorter. 50seconds
before the harvest timer terminates, LED 4 and WV de-energize. LED3comes on, DVR
energizes,energizingPMforthelast50secondsofharvest.Fordetails,see"II.C.3.e)
HarvestPumpTimer(S4dipswitch7)." CAUTION! S4 dip switch 7must remain in
the factory default position of 7 on. Otherwise, PM will not energize during the last
50 seconds of harvest. The pump-out timer (S4 dip switch 3 & 4) acts in place of the
harvesttimerduringcycleswithapump-out.Fordetails,see"II.C.3.c)Pump-OutTimer
(S4dip switch 3 & 4). The minimum total time allowed by CB for a complete harvest cycle
is 2 minutes. At the end of harvest, CB checks the position of F/S and proceeds to the
freeze cycle if it is closed or calls for a 1-minute ll cycle if it is open.
c) Freeze Cycle
LED 1 is on. Comp, FMRs, and PM continue. LLVs energize. HGVs de-energize. For
the rst 5 minutes, CB will not terminate the freeze cycle. At the end of 5 minutes, F/S
assumes control of the freeze cycle. As ice builds on the evaporator, the water level in
the tank lowers. The freeze cycle continues until F/S opens. There is a 15 second delay
before CB acknowledges an open F/S, CB then terminates the freeze cycle.

12
d) Pump-Out Cycle
LEDs 1, 4, 3, and 2 are on. Comp and FMRs remain energized, HGVs and WV
energize. LLVs de-energize. PM stops for 2 seconds, then DVR energizes, energizing
PM and DV for 10 seconds. Water is removed from the bottom of the tank and sent down
the drain. At the same time, water ows through the small F/S tube to power ush F/S.
When the pump-out timer terminates, pump-out is complete. CAUTION! S4 dip switch
3&4must remain in the factory default position of 3 off and 4 on. Otherwise,
DVwill not energize during pump-out.
The rst pump-out occurs after the 11th freeze cycle, then every 10th cycle thereafter.
The pump-out frequency control is factory set, and generally no adjustment is required.
However, where water quality is bad and the icemaker needs a pump-out more often,
the pump-out frequency can be adjusted. The pump-out frequency control (S4dip
switch5&6) can be set to have a pump-out occur every cycle, or every 2, 5, or
10cycles. Timing of the rst pump-out is dependent on S4 dip switch 5 & 6 settings. See
the table below.
S4 Dip Switch Setting Pump-Out
Frequency 1st Pump-Out
No. 5 No. 6
OFF OFF Every cycle After 2nd freeze cycle
ON OFF Every 2 cycles After 3rd freeze cycle
OFF ON Every 5 cycles After 6th freeze cycle
ON ON Every 10 cycles After 11th freeze cycle
e) Harvest Cycle
Sameastheinitialharvestcycle.See"II.B.1.b)InitialHarvestCycle."
Note: Unit continues to cycle until BC is satised or power is turned off. The unit always
restarts at the 1-minute ll cycle.
f) Shutdown
WhenBCisactivated(BCopen),theyellow"BCOPEN"LEDcomeson.Theunitthen
shutsdownasoutlinedinthetablebelow.Forfurtherdetails,see"IV.C.BinControl
CheckandCleaning."
Cycle at Bin
Control Activation
Shutdown
Fill Cycle 15 seconds after activation.
Harvest Cycle At the end of the harvest cycle, or up to 15 seconds into the freeze cycle if activated
at the end of the harvest cycle.
Freeze Cycle 15 seconds after activation if activated at least 15 seconds before the 5-minute short
cycle protection timer terminates. Otherwise, at the end of the next harvest cycle.
Legend: BC–bin control; CB–control board; Comp–compressor; DV–drain valve;
DVR–drain valve relay (X10); FMRs–fan motors-remote; F/S–oat switch;
HGVs–hot gas valves (KMS and SRK); LLVs–liquid line valves (KMS and SRK);
PM–pump motor; WV–inlet water valve

13
2. Sequence Flow Chart
F/S check
1 to 3-min. timer in control (S4 dip switch 1 & 2)
"G" Control Board Sequence Flow Chart
1. 1-Minute Fill
Cycle
Cycle Steps 2. Harvest Cycle
•WVtime:6min.orthelengthofharvestminus50sec.
(S4 dip switch 7), whichever is shorter.
•Maximumharvesttime:20min.
Thermistor in control
3. Freeze Cycle
•Minimumfreezetime:5min. •Maximumfreezetime:freezetimersetting
(S4 dip switch 9 & 10)
F/S in control
4. Pump-Out Cycle
•Factorysetforevery
10th cycle
(S4 dip switch 5 & 6) •PMstops,thenDVR
energizes, energizing PM and DV
(S4 dip switch 3 & 4)
WV energized
F/S open
WV continues Comp energized FMRs energized HGVs energized
Thermistor temperature reaches 48°F (9°C) (3.9 kΩ or less). Harvest timer starts.
F/S open
Comp continues FMRs continue PM continues LLVs energized HGVs de-energized
F/S closed
Comp/FMRs continue WV energizes PM stops for 2 sec. DVR energizes, energizing PM and DV for 10 sec., each 1,2, 5, or 10 cycles. HGVs energized LLVs de-energized
F/S check
Sartup begins here after 5-sec. delay
If F/S is open, compressor stops and cycle returns to 1-Minute Fill Cycle
5-min. timer in control
F/S closed
F/S open or freeze timer terminates
50 sec.
PM energized WV de-energized
Harvest Pump Timer
KMS-822MLH/SRK-10H
Legend: BC–bin control Comp–compressor DV–drain valve DVR–drain valve relay FMRs–fan motors-remote
F/S–oat switch HGVs–hot gas valves (KMS and SRK) LLVs–liquid line valves (KMS and SRK) PM–pump motor WV–inlet water valve
1. Bin Full
Shutdown Delay: •Fill Cycle – 15 sec. after activation. •Harvest Cycle – At the end of the harvest cycle, or up to 15 sec. into the
freeze cycle if activated at the end of the harvest cycle.
•Freeze Cycle – 15 sec. after activation if activated at least 15 sec. before
the 5-min. short cycle protection timer terminates. Otherwise, at the end of the next harvest cycle.
Shutdown andRestart
BC Operation
BC open Green"BCCLOSED"LEDoff Yellow"BCOPEN"LEDon
Yellow"BCOPEN"LEDcontinues All components de-energized
2. Icemaker Off All components de-energized.
3. Ice Level Lowered
Ice level lowered. No ice pressing against BC actuator paddle. Icemaker starts at "1.1-MinuteFillCycle."
To 1 above
BC closed Green"BCCLOSED"LEDon Yellow"BCOPEN"LEDoff
Components Energized when the Control Switch is in the "WASH" Position The"WASH"positiononthecontrolswitchisusedwhencleaningandsanitizingtheunit.Wheninthe"WASH"position, power is supplied to the pump motor. With the cleaning valve closed, the cleaner and sanitizer ow over the outside of the evaporator plate assembly. With the cleaning valve open, the cleaner and sanitizer ow over both the outside and the inside of the evaporator plate assembly.
Note: Close the cleaning valve after cleaning and sanitizing are complete, otherwise the unit will not re-start when the
controlswitchisplacedinthe"ICE"position.

14
C. Control Board
•A Hoshizaki exclusive solid-state control board is employed in Hoshizaki Crescent
Cubers.
•All models are pretested and factory set.
CAUTION
1. The control board is fragile; handle very carefully.
2. The control 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 before handling or replacing the control board.
3. Do not touch the electronic devices on the control board or the back of the
control board.
4. Do not change wiring and connections. Do not misconnect K3, K4, and K5,
because the same connector is used for the thermistor, bin control, and oat
switch.
5. Always replace the whole control board assembly if it goes bad.
6. Do not short out power supply to test for voltage.

15
1. Control Board Layout
"G" Control Board
Part Number 2A3792-01
"G" Control Board
• "ALARM RESET" Button
• "OUTPUT TEST" Button
(used to test relays on control board)
• WHITE K3 Connector
Harvest Control
(thermistor)
• RED K4 Connector
Bin Control
• Label
(control board revision
level indicated on label
on side of relay)
• BLACK K5 Connector
Float Switch
• Part Number
• K1 Ten-Pin Connector
Pins #1 through #10
#1, 9 Magnetic Contactor
#2 Hot Gas Valves (HGVs)
(KMS and SRK)
#3 Liquid Line Valves (LLVs)
(KMS and SRK)
#4 Pump Motor (icemaking)
#5 Drain Valve Relay (DVR)
(pump motor during
harvest pump timer and
pump motor and drain
valve during pump-out)
#6 Inlet Water Valve (WV)
#7, 10 Component Power
Supply
#8 Open
• Bin Control Switch
Open LED (yellow)
• S4 Dip Switch
• Bin Control Switch
Closed LED (green)
• Alarm Buzzer
• Power LED (red)
(lights when power
is supplied to the
control board)
• LED 2 (X2 Relay)
Hot Gas Valves
(HGVs)
• LED 3 (X3 Relay)
Pump Motor (PM)
(on at harvest pump
time and pump-out)
• LED 4 (X4 Relay)
Inlet Water Valve (WV)
• LED 1 (X1 Relay)
Compressor (Comp),
Fan Motors-Remote
(FMRs), Liquid Line
Valves (LLVs)
• K2 Connector
Control Transformer
• S5 Dip Switch
• Relay LEDs
(4) (indicate
which relays are
energized as listed
below)

16
2. LED Lights and Audible Alarm Safeties
At startup, a 5-second delay occurs while the control board conducts an internal timer
check.Abeepoccurswhenthecontrolswitchismovedtothe"ICE"position.
The red LED indicates proper control voltage and remains on unless a control voltage
problem occurs. The green LEDs 1 through 4 energize and sequence from initial startup
as listed in the table below. Note that the order of the LEDs from the outer edge of the
controlboardis1,4,3,2.Fordetails,see"II.B.SequenceofOperation."
Sequence Step LED Energized
Components
Time LEDs are On
Min. Max. Avg.
1-Minute Fill Cycle 4 WV 1 minute
Harvest Cycle 1, 4, 2 Comp, FMRs, WV,
HGVs
2 minutes 20 minutes 3 to 5 minutes
Harvest Pump Timer 1, 3, 2 Comp, FMRs, DVR,
PM, HGVs
0 seconds 50 seconds harvest pump timer
setting
Freeze Cycle 1 Comp, FMRs, PM,
LLVs
5 minutes freeze timer
setting
30 to 35 minutes
Pump-Out Cycle 1, 4*, 3, 2 Comp, FMRs, HGVs,
WV*, DVR, PM, DV
10 seconds 20 seconds *pump-out timer
setting
The built-in safeties shut down the unit and have alarms as listed below.
No. of Beeps
(every 3 sec.) Type of Alarm Notes
1High Evaporator Temp.
(temperature > 127°F (53°C))
Check for harvest problem (stuck HGV), hot water
entering unit, stuck HM, or shorted thermistor.
2Harvest Backup Timer
(harvest > 20 min. for two cycles
in a row)
Check for open thermistor, HGV not opening, TXV or
LLVs leaking by, low charge, or inefficient Comp.
3Freeze Timer
(freeze > freeze timer setting for
two cycles in a row)
Timer is factory set using S4 dip
switch 9 & 10
Check for F/S stuck closed (up), WV leaking by, HGVs
leaking by, PM not pumping, TXV not feeding properly,
LLVs not opening, low charge, HM not bypassing, or
inefficient Comp.
Toresettheabovesafeties,pressthe"ALARMRESET"buttonwiththepowersupplyon.
6Low Voltage
(92Vac±5% or less)
Red LED turns off if voltage protection operates.
The control voltage safeties automatically reset when
voltage is corrected.
7High Voltage
(147Vac±5% or more)
Legend: Comp–compressor; DV–drain valve; DVR–drain valve relay; FMRs–fan
motors-remote; F/S–oat switch; HGVs–hot gas valves (KMS and SRK);
HM–headmaster (C.P.R.); LLVs–liquid line valves (KMS and SRK); PM–pump
motor; TXV–thermostatic expansion valve; WV–inlet water valve

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3. Controls and Adjustments
CAUTION
Dip switches are factory set. Failure to maintain factory settings may adversely
affect performance and warranty coverage. For more information, contact
Hoshizaki Technical Support at 1-800-233-1940.
a) Default Dip Switch Settings
The dip switches are factory set to the following positions:
S4 Dip Switch
S4 Dip Switch No. 1 2 3 4 5 6 7 8 9 10
KMS-822MLH OFF OFF OFF ON ON ON ON OFF OFF ON
S5 Dip Switch (Do Not Adjust)
S5 Dip Switch No. 12345
KMS-822MLH OFF OFF OFF OFF OFF
Freeze Timer (9 & 10)
Pump-Out Frequency Control (5 & 6)
Pump-Out Timer (3 & 4)
(Do not adjust out of factory setting)
Harvest Timer (1 & 2)
Harvest Pump Timer (7)
(Do not adjust)
Factory Use (8)
b) Harvest Timer (S4 dip switch 1 & 2)
The harvest timer starts when the thermistor reads 48°F (9°C) at the evaporator outlet
and the control board reads the thermistor's 3.9 kΩ signal. The harvest timer is factory
set, and generally no adjustment is required. However, a setting longer than the factory
setting may be advised in cases where harvest needs to be prolonged for extra cleaning.
Before changing this setting, contact your local Hoshizaki distributor or Hoshizaki
Technical Support for recommendations. Keep in mind that setting the harvest timer to a
longer setting decreases 24-hour production.
The pump-out timer (S4 dip switch 3 & 4) acts in place of the harvest timer during cycles
withapump-out.Fordetails,see"II.C.3.c)Pump-OutTimer(S4dipswitch3&4)."
S4 Dip Switch Setting Time
(seconds)
No. 1 No. 2
OFF OFF 60
ON OFF 90
OFF ON 120
ON ON 180

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c) Pump-Out Timer (S4 dip switch 3 & 4)
CAUTION
Factory set. Do not adjust. S4 dip switch 3&4must remain in the factory
default position of 3 off and 4 on. Otherwise, the drain valve will not energize
during pump-out.
At the end of a freeze cycle when a pump-out is called for, the pump motor stops for
2seconds, then the drain valve relay energizes, energizing the pump motor and drain
valve. Water is removed from the bottom of the tank and sent down the drain. At the
same time, water ows through the small oat switch tube to power ush the oat switch.
The pump-out drains the water tank for the time determined by the pump-out timer. The
pump-out timer also acts in place of the harvest timer during cycles with a pump-out. The
pump-out timer is factory set, do not adjust.
Note: The drain valve shares power with the inlet water valve during the pump-out cycle.
Therefore,S4dipswitch3&4mustbesetto3offand4on.See"III.B.Wiring
Diagram."
S4 Dip Switch Setting Time (seconds) Inlet
Water
Valve
No. 3 No. 4 T1 T2
OFF OFF 10 150 closed
ON OFF 10 180 closed
OFF ON 10 120 open
ON ON 20 180 closed
T1: Time to drain the water tank
T2: Harvest timer at pump-out
d) Pump-Out Frequency Control (S4 dip switch 5 & 6)
The pump-out frequency control is factory-adjusted to drain the water tank every
10cycles, and generally no adjustment is required. However, where water quality is
bad and the icemaker needs a pump-out more often, the pump-out frequency can be
adjusted as shown in the table.
Timing of the rst pump-out is dependent on S4 dip switch 5 & 6 settings. See the table
below.
S4 Dip Switch Setting Pump-Out
Frequency 1st Pump-Out
No. 5 No. 6
OFF OFF Every cycle After 2nd freeze cycle
ON OFF Every 2 cycles After 3rd freeze cycle
OFF ON Every 5 cycles After 6th freeze cycle
ON ON Every 10 cycles After 11th freeze cycle

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e) Harvest Pump Timer (S4 dip switch 7)
CAUTION
Factory set for proper operation. Do not adjust. Adjustment outside of the
factory default setting may result in damage to the icemaker.
Depending on the harvest pump timer setting, the pump motor energizes and runs the
last 0 or 50 seconds of harvest. When the pump motor is on, water circulates over the
evaporator. The water valve is open during harvest for a maximum of 6 minutes or the
length of harvest minus 0 or 50 seconds (determined by the harvest pump timer setting),
whichever is shorter. When S4 dip switch 7 is in the on position, the drain valve relay
energizes through the control board K1 ten-pin connector pin #5(DBu wire). The drain
valve relay then energizes the pump motor for the last 50 seconds of harvest.
Note: The drain valve is not energized during the last 50 seconds of harvest because it
shares power with the inlet water valve which de-energizes the last 50 seconds of
harvest.See"III.B.WiringDiagram."
S4 Dip Switch Setting Pump Motor
Time (seconds)
No. 7
ON 50
OFF 0
f) Factory Use (S4 dip switch 8)
Factory set for proper operation. Do not adjust. This must be left in the factory default
position.
g) Freeze Timer (S4 dip switch 9 & 10)
CAUTION
Adjust to proper specication, or the unit may not operate correctly.
The freeze timer setting determines the maximum allowed freeze time to prevent possible
freeze-up issues. Upon termination of the freeze timer, the control board initiates the
harvest cycle. After 2 consecutive freeze timer terminations, the control board shuts
downtheicemaker.Inthiscase,see"IV.F.3.LowIceProduction"forpossiblesolutions.
The freeze timer is factory set, and generally no adjustment is required. Before changing
this setting, contact your local Hoshizaki distributor or Hoshizaki Technical Support for
recommendations.
S4 Dip Switch Setting Time
(minutes)
No. 9 No. 10
OFF OFF 60
OFF ON 50
ON OFF 70
ON ON 60

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h) Float Switch Control (S5 dip switch 1)
CAUTION
Factory set. Do not adjust. Otherwise, the unit will not operate correctly.
S5 dip switch 1 allows for single or double oat switch applications. The KMS-822MLH
uses a single oat switch.
S5 Dip Switch Setting Single or Double Float
Switch Application
No. 1
OFF Single
On Double
i) Rell Counter (S5 dip switch 2 through 5)
CAUTION
Factory set. Do not adjust. Otherwise, the unit will not operate correctly.
S5 dip switch 2 through 5 allows for rells during the freeze cycle.
The KMS-822MLH does not rell.
D. Control Switch
Thecontrolswitchhasthreepositions:"OFF"forpoweroff,"ICE"foricemaking,and
"WASH"toactivatethewaterpumpwhencleaningandsanitizing.