Hoshizaki DIM-30DE-2 User manual

DIM-30DE-2
E2HA-990 (073120)
CUBE ICE DISPENSER
SERVICE MANUAL

i
CONTENTS PAGE
I. GENERAL INFORMATION --------------------------------------------------------------------------1
1. DIMENSIONS/CONNECTIONS ----------------------------------------------------------------1
2. CONSTRUCTION ----------------------------------------------------------------------------------3
[a] OVERVIEW--------------------------------------------------------------------------------------3
[b] WATER CIRCUIT AND MACHINE COMPARTMENT---------------------------------5
II. CONTROLLER BOARD -----------------------------------------------------------------------------6
1. CONFIGURATION ---------------------------------------------------------------------------------6
[a] CONTROLLER BOARD LAYOUT ---------------------------------------------------------6
[b] INPUT/OUTPUT LAYOUT -------------------------------------------------------------------7
[c] BEFORE CHECKING CONTROLLER BOARD ----------------------------------------8
[d] SWITCH OPERATION------------------------------------------------------------------------9
[e] VERSION COMPARISON ----------------------------------------------------------------- 11
2. OPERATION --------------------------------------------------------------------------------------- 12
[a] SOFT START---------------------------------------------------------------------------------- 12
[b] WATER PAN OPENS ----------------------------------------------------------------------- 12
[c] DEFROST CYCLE--------------------------------------------------------------------------- 12
[d] WATER PAN CLOSES---------------------------------------------------------------------- 13
[e] FREEZE CYCLE ----------------------------------------------------------------------------- 13
[f] FREEZE COMPLETION CONTROL---------------------------------------------------- 14
[g] WATER SUPPLY CONTROL-------------------------------------------------------------- 17
[h] AMBIENT TEMPERATURE CORRECTION ------------------------------------------ 17
[i] DIMPLE DIAMETER SETTING----------------------------------------------------------- 17
[j] BIN CONTROL CYCLE--------------------------------------------------------------------- 18
[k] RESET SWITCH ----------------------------------------------------------------------------- 18
[l] 7-SEGMENT LED---------------------------------------------------------------------------- 18
3. MODE SETTING --------------------------------------------------------------------------------- 19
[a] WATER CIRCUIT FLUSH MODE-------------------------------------------------------- 19
[b] MAINTENANCE MODE -------------------------------------------------------------------- 20
[c] DISPLAY MODE (LOG CLEARING) ---------------------------------------------------- 27
[d] MODEL CODE SETTING MODE -------------------------------------------------------- 28
4. 7-SEGMENT DISPLAY-------------------------------------------------------------------------- 30
[a] NORMAL MODE ----------------------------------------------------------------------------- 30
[b] MAINTENANCE MODE -------------------------------------------------------------------- 30
[c] DISPLAY MODE------------------------------------------------------------------------------ 32
5. ERROR CODES ---------------------------------------------------------------------------------- 33
[a] ERROR CODES, CAUTION CODES--------------------------------------------------- 33
[b] SERVICE DIAGNOSIS --------------------------------------------------------------------- 34
6. TROUBLESHOOTING -------------------------------------------------------------------------- 35
[a] INSTRUCTIONS FOR SERVICE ENGINEER---------------------------------------- 35
[b] CHECKING CONTROLLER BOARD --------------------------------------------------- 35
7. REMOVAL AND REPLACEMENT------------------------------------------------------------ 36
8. TIMING CHART----------------------------------------------------------------------------------- 38

ii
III. OPERATING INSTRUCTIONS------------------------------------------------------------------ 41
1. IN CASE OF DIRTY WATER ------------------------------------------------------------------ 41
2. PREPARING THE ICE DISPENSER FOR LONG STORAGE ------------------------ 42
IV. MAINTENANCE INSTRUCTIONS ------------------------------------------------------------- 43
1. MACHINE EXTERIOR, SPOUT, ICE STATION------------------------------------------- 43
2. AIR FILTER----------------------------------------------------------------------------------------- 43
3. DRAIN PAN, STORAGE BIN, FRONT PANEL (UPPER)------------------------------- 44
4. ICE STATION, DRAIN TRAP ------------------------------------------------------------------ 44
5. WATER VALVE------------------------------------------------------------------------------------ 45
6. ICEMAKING WATER SYSTEM --------------------------------------------------------------- 47
V. TECHNICAL INFORMATION--------------------------------------------------------------------- 50
1. WATER CIRCUIT AND REFRIGERANT CIRCUIT--------------------------------------- 50
2. WIRING DIAGRAM ------------------------------------------------------------------------------ 51
3. PERFORMANCE DATA------------------------------------------------------------------------- 52
VI. SERVICE DIAGNOSIS --------------------------------------------------------------------------- 53
1. NO ICE PRODUCTION ------------------------------------------------------------------------- 53
2. LOW ICE PRODUCTION----------------------------------------------------------------------- 55
3. ABNORMAL ICE ---------------------------------------------------------------------------------- 55
4. OTHERS-------------------------------------------------------------------------------------------- 56
VII. REMOVAL AND REPLACEMENT OF COMPONENTS --------------------------------- 57
1. PANELS--------------------------------------------------------------------------------------------- 57
[a] FRONT PANEL (UPPER) (serial number: K0 or earlier) --------------------------- 57
[b] FRONT PANEL (LOWER) (serial number: K0 or earlier) -------------------------- 57
[c] FRONT PANEL (serial number: K1 or later)------------------------------------------- 57
[d] TOP PANEL ----------------------------------------------------------------------------------- 58
[e] AIR GUIDE------------------------------------------------------------------------------------- 58
[f] REFRIGERATOR COVERS--------------------------------------------------------------- 58
[g] SWITCH BOX--------------------------------------------------------------------------------- 59
2. SERVICE FOR REFRIGERANT LINES ---------------------------------------------------- 60
[a] SERVICE INFORMATION ----------------------------------------------------------------- 60
[b] REFRIGERANT RECOVERY------------------------------------------------------------- 61
[c] EVACUATION AND RECHARGE -------------------------------------------------------- 61
3. COMPRESSOR----------------------------------------------------------------------------------- 62
4. DRIER ----------------------------------------------------------------------------------------------- 63
5. EVAPORATOR ------------------------------------------------------------------------------------ 64
6. HOT GAS VALVE--------------------------------------------------------------------------------- 65
7. WATER PAN ASSEMBLY ---------------------------------------------------------------------- 66
8. PUMP MOTOR------------------------------------------------------------------------------------ 67
9. WATER VALVE------------------------------------------------------------------------------------ 67
10. ACTUATOR MOTOR ---------------------------------------------------------------------------- 68
11. CAM ARM ------------------------------------------------------------------------------------------ 69
[a] CAM ARM (A) - ACTUATOR MOTOR SIDE ------------------------------------------ 69
[b] CAM ARM (B) - REAR SIDE -------------------------------------------------------------- 69

iii
12. CONTROLLER BOARD ------------------------------------------------------------------------ 71
[a] MODIFICATION ------------------------------------------------------------------------------ 71
[b] REPLACEMENT ----------------------------------------------------------------------------- 72
13. THERMISTOR FOR CUBE CONTROL----------------------------------------------------- 73
14. FAN MOTOR -------------------------------------------------------------------------------------- 74
15. GEAR MOTOR------------------------------------------------------------------------------------ 74
16. BIN CONTROL SWITCH ----------------------------------------------------------------------- 75
17. PUSH BUTTON SWITCH AND PILOT LAMP--------------------------------------------- 76

1
ITEM MODEL DIM-30DE-2
Hoshizaki Cube Ice Dispenser
AMPERAGE
SHAPE OF ICE Cube Approx. 28x28x32mm
Approx. 15kg
Rated Motor: 320/340W (Power factor: 63/79%)
HEAT REJECTION STORAGE BIN
350mm(W)x526mm(D)x1590(-1635)mm(H) 600/630W (520/540kcal/h) (AT. 32°C, WT. 21°C)
ABS Plastic, Insulation: Polyurethane Foam
CABINET
Approx. 1700g/min
ICE MAKING SYSTEM Cell Type
Auger Operated By Push Switch
Hot Gas Defrost Thermistor, Timer R134a/200g Thermistor
COMPRESSOR CONDENSER EVAPORATOR REFRIGERANT
Microswitch With Time Delay Timer, Water Pan’s movement
BIN CONTROL
Fin and Tube Type, Air-cooled Hermetic Electroless Nickel Plated Copper Tube on Sheet and Cells Capillary Tube
ABS (90-135mm)
450(W)x670(D)x1763(H)mm 65kg (Gross Weight 71kg) Mounting Brace (Wall Mounting), Installation Kit
ADJUSTABLE LEGS
NET WEIGHT PACKAGE
ACCESSORIES
OPTIONAL PARTS Mounting Brace (Floor Mounting)
*We reserve the right to make changes in specifications and design without prior notice.
Class I Appliance, 5A Fuse
Auto-reset Overload Protector
WATER INLET Rc1/2
POWER CORD 2000 LONG OUTSIDE
ADJUSTABLE LEGS
1506
1500
410
125
175
100
DRAIN OUTLET R3/4
AIR
635
66 398
(187)
(26)
204
62
AIR
503
(85) 23
280
135 100
SAFETY BRACKET INSTALLATION (FLOOR MOUNTING)
OPTIONAL
BRACE
BOLT
SAFETY BRACKET INSTALLATION (WALL MOUNTING)
MACHINE SCREW (M4)
OPTIONAL
BRACE
BOLT
AIR
526
(37)
AIR
MACHINE SCREW (M4)
220
350
PUSH SWITCH
SPOUT
1500
1590
935
32
90
28632
180
CORD ANCHORAGE
2-M4 THREAD MOUNT. BRACE
POWER SUPPLY ELECTRIC CONSUMPTION ICE PRODUCTION PER 24h ICE PRODUCTION PER CYCLE MAX. STORAGE CAPACITY WATER CONSUMPTION PER 24h OPERATING CONDITIONS COMPRESSOR PROTECTION ELECTRIC CIRCUIT PROTECTION ICE MAKING WATER CONTROL HARVESTING CONTROL REFRIGERANT CONTROL ICE DISPENSING SYSTEM CONNECTIONS
-ELECTRIC
-WATER SUPPLY
-DRAIN
HARVESTING SYSTEM OUTSIDE DIMENSIONS ICE RELEASE CAPACITY ICE MAKING CONTROL
Controller Board
1. Install the ice maker properly in accordance with the
instructions on location, water supply/drain connections and electrical connections stated in the instruction manual provided. Allow 10mm extra space at the installation site to meet any installation requirements (additional spacing is also required for proper air flow and pipe connections).
2. The ice production depends on the ambient and water
temperatures. Refer to the instruction manual.
3. The adjustable legs are optional.
Consult with our sales staff.
4. Product code: E2HA-D010
Ambient Temp.: 1 - 40°C, Water Supply Pressure: 5 - 35°C Water Supply Pressure: 0.07 - 0.78MPa (0.7 - 7.8bar), Voltage Range: Rated Voltage ±6/10% Approx. 0.15/0.17m3(Ambient Temp. 10°C, Water Temp. 10°C)
Approx. 0.10/0.11m3(Ambient Temp. 21°C, Water Temp. 15°C)
Approx. 0.08/0.09m3(Ambient Temp. 32°C, Water Temp. 21°C)
X-type Con. (with CONT./UK Plug) Inlet Rc1/2 (rear side) Outlet R3/4 (rear side) Plastic (Delivery Stage, Louver) Colored Steel (Top, Side) Galvanized Steel (Rear) Acrylic Painted Steel (Front) Approx. 40/42kg (Ambient Temp. 10°C, Water Temp. 10°C) Approx. 36/36kg (Ambient Temp. 21°C, Water Temp. 15°C) Approx. 28/30kg (Ambient Temp. 32°C, Water Temp. 21°C) Approx. 0.61kg/27 pcs. (Ambient Temp. 32°C, Water Temp. 21°C) Running: 2.1/1.8A Rated Motor: 2.1/1.8A Starting: 13/13A 1 Phase 220-240/230V 50/60Hz Capacity: 0.6kVA (2.1A)/0.58kVA (2.0A)
I. GENERAL INFORMATION
1. DIMENSIONS/CONNECTIONS
Auxiliary code: K0 or earlier

2
Auxiliary code : K1 or later

3
2. CONSTRUCTION
[a] OVERVIEW
Auxiliary code: K0 or eariler
Removable Side
Access Panel
Louver
Front Panel (Upper)
Front Panel (Lower)
Pilot Lamp
Spout
Ice Station
Air Filter
Switch Cover
Top Panel
Nameplate
Push Button
Power Switch

4
Auxiliary code : K1 or later
Removable Side
Access Panel
Louver
Front Panel
Pilot Lamp
Spout
Ice Station
Air Filter
Switch Cover
Top Panel
Nameplate
Push Button
Power Switch

5
[b] WATER CIRCUIT AND MACHINE COMPARTMENT
Condenser Drier
Access Valve
Water Valve
Water Supply Pipe
Pump Motor
Actuator Motor
Gear Motor
Drain Hose
Power Switch
Air Guide
Water Supply Inlet
Accumulator
Evaporator
Water Tank
Drain Pan
Bin Control Switch
Auger
Drain Outlet
Control Box
Rear Access Panel
Compressor
Hot Gas Valve
Adjustable Leg Fan Motor

6
II. CONTROLLER BOARD
1. CONFIGURATION
Part Number P01873-01 P01873-02
Evaporator Tin plated Electroless nickel plated
[a] CONTROLLER BOARD LAYOUT
Main Board
Sub Board
Combination

7
Open Button
Close Button
Reset Button
7-Segment Double-
Digit Display
Bin Control Switch / Pressure Switch /
Condenser Thermistor Input XA Connector (6P)
Hall IC Input XA Connector (4P)
Cube Control Thermistor Input XA Connector (2P)
Data Input/Output PA Connector (8P)
Actuator Drive Output VH Connector (3P)
Pump Motor / Hot Gas Valve / Fan Motor / Water Valve /
Compressor AC Relay Drive Output VH Connector (9P)
Fuse
P01992-01
6.3A
220-240V AC Input
VYH Connector (3P)
AC High
Voltage Circuit
AC Low Voltage,
DC Circuit
10.5V AC Input VH Connector (2P)
[b] INPUT/OUTPUT LAYOUT

8
[c] BEFORE CHECKING CONTROLLER BOARD
BEFORE CHECKING CONTROLLER BOARD
Check the power source voltage and the components as shown in the table below.
Component Procedure Normal
1. Thermistor
(on evaporator)
Holder
Screw
Thermistor
Evaporator
NOTICE
Thermistor sensor part is fragile,
glass sealed. Handle with care.
* Disconnect the connector CN13 on the
board.
* Remove the screw and the thermistor
holder on the evaporator.
* Immerse the sensor part in a glass
containing ice and water for 5 minutes.
* Check the resistance between CN13
connector pins.
* Replace the thermistor in its correct
position.
* Connect CN13.
5 -7 kilohms
2. Bin Control Switch Manually set the micro switch in the
TRIP and RESET positions, and check
the period.
Approx.
TRIP (Closed) 10 sec.
RESET (Open) 80 sec.

9
[d] SWITCH OPERATION
1) The following is the switch operation flow in different modes. When pressed and
released, the switch detects the operation by its pressing duration.
Same as normal mode
except display change
“on” appears after no
switch operation for 30s
Freeze setting mode
Flush mode (press 3s)
Freeze setting mode
Display mode (press 3s)
Water pan opens (initial cycle)
Maintenance mode (press 3s)
Normal mode
Flush mode
Check contents
Water pan starts
to open
Actuator motor stops
(* Water pan closing)
Return to normal
mode (press 3s)
Freeze temp
setting mode
Maintenance mode
Display mode
P01873-01
(Ver. 1.8D or earlier)
P01873-02
(Ver. 1.2F or earlier)
P01873-01
(Ver. 1.9A or later)
P01873-02
(Ver. 1.4A or later)

10
2) To clear the current model code information and enter the model setting mode, press
the up and down switches together for 15 seconds while the model code is indicated
in the display mode (see “3. [c] DISPLAY MODE”).
Model setting
mode
Return to
normal mode
P01873-01
(Ver. 1.9A or later)
P01873-02
(Ver. 1.4A or later)
P01873-01
(Ver. 1.8D or earlier)
P01873-02
(Ver. 1.2F or earlier)

11
[e] VERSION COMPARISON
Operator P01873-01 (Ver. 1.9A or later),
P01873-02 (Ver. 1.4A or later)
P01873-01 (Ver. 1.8D or earlier),
P01873-02 (Ver. 1.2F or earlier)
End-user ● Control mode: Normal
● No. 2: Target integrated freeze
completion temperature cannot be
changed.
● Target integrated freeze completion
temperature cannot be changed by
pressing “SERVICE 1” or “SERVICE 2”
button on control panel
* Control label has been changed.
● Control mode: Normal
● No. 2: Target integrated freeze
completion temperature can be changed.
● Target integrated freeze completion
temperature can be changed every 0.5°C
by pressing “▲UP” or “▼DOWN” button
on control panel.
● Change range: -5°C to -40°C
Service
engineer
● Control mode: Maintenance mode
· Press and hold “RESET” button for more
than 3 seconds to show setting number “1”.
· Select desired number with “SERVICE
1(▲)” or “SERVICE 2(▼)”.
· Press “RESET” button to ash set value
on display.
· Change set value with “1(▲)” or “2(▼)”.
· Press “RESET” button to memorize set
value and return to setting number.
· Leave buttons untouched for 30 sec to
shift to normal mode.
● All settings are adjustable.
● Adjustable range: Nos. 2 and 3 have
additional setting ranges.
No. 2: Target integrated freeze completion
temperature
Factory setting ± 3°C * every 0.5°C
No. 3: Target integrated freeze completion
time
Factory setting ± 2 min * every 1
min
* Factory settings cannot be changed,
but set values can be changed within the
above setting ranges.
● Control mode: Maintenance mode
· Press and hold “RESET” button for
more than 3 seconds to show setting
number “1”.
· Select desired number with “▲” or “▼”.
· Press “RESET” button to ash set value
on display.
· Change set value with “▲” or “▼”.
· Press “RESET” button to memorize set
value and show setting number.
· Leave buttons untouched for 30 sec to
shift to normal mode.
● All settings are adjustable.
● Adjustable range: e.g. Nos. 2 and 3
No. 2: Target integrated freeze
completion temperature
-5 to -40°C * every 0.5 °C
No. 3: Target integrated freeze
completion time
5 to 90 min * every 1 min
* Factory settings can be changed.

12
Setting number P01873-01 (Ver. 1.9A or later),
P01873-02 (Ver. 1.4A or later)
P01873-01 (Ver. 1.8D or earlier),
P01873-02 (Ver. 1.2F or earlier)
No. 71
Hot gas valve ON time to
prevent ice stuck
Setting range: 0 to 10 sec
* every 1 sec
Setting range: 0 to 20 sec
* every 1 sec
No. 72
Hot gas valve OFF time to
prevent ice stuck
Not adjustable Setting range: 0 to 60 sec
* every 1 sec
OFF time = 30 sec − No. 71 set
value (sec)
2. OPERATION
This service manual species the basic operation of the controller board “Ver. 1.0A”.
[a] SOFT START
1) When the power supply is turned on, the 7-segment LED shows “on” and the hot gas
valve opens. After 30 seconds, the defrost cycle starts.
* If the reset switch is pressed during the 30-second standby time, the unit resets
soft start and immediately starts operation.
[b] WATER PAN OPENS
1) The hot gas valve opens, the actuator motor starts, and the water pan starts to open.
2) After 20 seconds, the water valve opens to supply defrosting water (water pan
cleaning water) for a specic time.
* The defrosting water supply time varies between the water temperatures above
and below 13°C.
* In the initial cycle, the water temperature is not detected and assumed to be below
13°C, resulting in a longer defrosting water supply time.
* The defrosting water supply time is adjustable in the maintenance mode (see “3. [b]
MAINTENANCE MODE”).
3) The opening backup timer starts counting when the water pan starts to open. If the
hall IC does not turn on within 3 minutes, the display shows “EE” and the unit stops
for 60 minutes. If the error recurs after the unit resumes operation, the display shows
“EE” and the unit shuts down (recorded as “E3” in error history).
[c] DEFROST CYCLE
1) After the water pan opens, the hot gas valve opens until the defrost completion
temperature is reached.
2) If the defrost completion temperature is not reached even when the defrost backup
timer counts up (30 minutes after water pan starts to open), the display shows “E2”
and the unit stops.
If the hot gas valve fails to open, the unit may stop with the “E2” error.

13
* The defrost completion temperature is adjustable in the maintenance mode (see “3.
[b] MAINTENANCE MODE”).
[d] WATER PAN CLOSES
1) When the cube control thermistor senses the evaporator temperature above the
defrost completion temperature, the hot gas valve closes, the fan motor starts, and
the water pan starts to close.
2) The closing backup timer starts counting when the water pan starts to close. If the
hall IC does not turn on within 3 minutes, the display shows “EE” and the unit stops
for 60 minutes. If the error recurs after the unit resumes operation, the display shows
“EE” and the unit shuts down (recorded as “E4” in error history).
* In the initial cycle or when the water temperature is below 13°C, the water valve
opens to supply defrosting water for 10 seconds after the water pan starts to close.
[e] FREEZE CYCLE
1) When the water pan closes and the hall IC turns on, the water valve opens to supply
icemaking water for a specic time. The icemaking water supply time varies between
startup, reset, and the end of bin control cycle.
* The icemaking water supply time and additional water supply time are adjustable
in the maintenance mode (see “3. [b] MAINTENANCE MODE”).
2) After icemaking water has been supplied, the pump motor starts.
3) After 30 seconds, the cube control thermistor senses the temperature that will be
added with a predetermined o󰀨set value and used as the water temperature in the
freeze cycle, water pan opening cycle, defrost cycle, and water pan closing cycle.
* The o󰀨set value for the cube control thermistor temperature is adjustable in the
maintenance mode (see “3. [b] MAINTENANCE MODE”).
4) The freeze cycle is considered to be 100% complete when the predetermined target
integrated values are reached.
* The target integrated values (temperature and time) for the freeze completion are
adjustable in the maintenance mode (see “3. [b] MAINTENANCE MODE”).
5) To reduce ice forming on the water pan when the freeze completion rate reaches
100% at an ambient temperature below 30°C, the hot gas valve opens and closes
two times for a specic time to raise the water pan temperature. Then, the actuator
motor starts to open the water pan.
While the hot gas valve opens and closes, the freeze cycle is not considered to be
complete and the pump motor and fan motor keep running.
* The ambient temperature setting and hot gas valve opening/closing time are
adjustable in the maintenance mode (see “3. [b] MAINTENANCE MODE”).
6) Even if the freeze backup timer counts up (45/60 minutes after water pan starts to
close), the unit stops with the “E1” error when the evaporator temperature is above
0°C.
If the hot gas valve fails to close, the unit may stop with the “E1” error.
* The backup timer setting is adjustable in the maintenance mode (see “3. [b]
MAINTENANCE MODE”).

14
[f] FREEZE COMPLETION CONTROL
1) The target integrated values (cube control thermistor temperature and freeze cycle
time) are set for freeze completion.
* The target integrated freeze completion temperature and time are adjustable in the
maintenance mode (see “3. [b] MAINTENANCE MODE”).
2) After the cube control thermistor senses a temperature below 0°C, the cube control
thermistor temperature and freeze cycle time are integrated every second.
3) When the integrated values reach the target, the freeze cycle completes.
Cube control
thermistor temp
Integration begins
when ice starts to form
Time: 12 min
Temperature: -18°C
0°C
Freeze cycle time (min)
Integration
Evaporator temp (°C)
As the previous freeze completion control depended on the freeze completion
temperature only, the dimple size varied in 1) spring/fall, 2) summer, and 3) winter even
at the same freeze completion temperature.
For example, when the freeze completion temperature is -18°C and the dimple size is
5 mm, the freeze cycle time becomes longer and dimple size smaller in summer, and
the freeze cycle time becomes shorter and dimple size larger in winter.

15
2) Summer
3) Winter
1) Spring/fall
Dimple size 5mm Smaller dimple size
Larger dimple size
Evaporator temp (°C) Evaporator temp (°C)
Evaporator temp (°C)
Freeze cycle time (min) Freeze cycle time (min)
Freeze cycle time (min)
-18°C
-18°C
-18°C
Comparison of the evaporator temperature curves nds that the red-colored area varies
in di󰀨erent seasons.
Note: It is assumed that the water temperature is the same in these examples as the
time to reach the zero degrees mark is di󰀨erent.
2) Summer
3) Winter
1) Spring/fall
Dimple size 5mm Smaller dimple size
Larger dimple size
Evaporator temp (°C)
Evaporator temp (°C)
Evaporator temp (°C)
Freeze cycle time (min) Freeze cycle time (min)
Freeze cycle time (min)
-18°C
-18°C
-18°C
This area varies

16
This area corresponds to the energy on ice. Making these di󰀨erent areas into one can
equalize the dimple size.
To calculate the energy required for ice production, the actual ice production area under
0°C in the evaporator temperature curve is approximated into a triangle.
This area can be calculated by
Time x temperature ÷ 2
Therefore,
Energy required for ice production = time x temperature ÷ 2
Time
Temperature
0°C
Freeze cycle time (min)
Evaporator temp (°C)
Time x temp ÷ 2
Providing the calculated energy to icemaking water can produce ice with xed dimple
size not a󰀨ected by ambient conditions.
Actually, after the evaporator temperature becomes 0°C, the icemaker adds thermistor
sensed temperature every second and continues ice production until the energy value
calculated above (target freeze completion value) is reached.
To have stable ice production, it is necessary to calculate icemaking energy internally
with the microprocessor. This energy calculation requires not just temperature but also
time as shown in the above graph.
For this reason, both temperature and time are used to determine freeze completion.