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 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 T echnical Support Dep artment for
assistance.
HOSHIZAKI AMERICA, INC.
618 Highway 74 South
Peachtree City , GA 30269
Attn: HOSHIZAKI T echnical Support Department
Phone: 1-800-233-1940 T echnical Service
(770) 487-2331
Fax:(770) 487-3360
NOTE: T o expedite assistance, all correspondence/communication MUST include the following
information:
• Model Number
• Serial Number
• Complete and detailed explanation of the problem
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Please review this manual. It should be read carefully before the icemaker is serviced
or maintenance operations are 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
We reserve the right to make changes in specifications and design without prior notice.
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2. CONDENSING UNIT, URC-24F
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MODEL: URC-24F
SPECIFICATIONS
EXTERIOR
DIMENSIONS (W x D x H)
REFRIGERANT CHARGE
URC-24F
WEIGHT
CONNECTIONS
REFRIGERANT
ELECTRICAL
CONDENSER
AC SUPPLY VOLTAGE
AMBIENT CONDITION
Galvanized Steel
36” x 19-3/4” x 43-3/4”
(915 x 501 x 1111 mmmm)
R404A 11 lbs. (5000 g)
Net 168 lbs. (76 kg)
Shipping 179 lbs. (81 kg)
One Shot Couplings (Aeroquip)
Permanent Connection
Air-cooled
208-230/60/1
Min. -20°F - Max. +122°F
(-29°C to +50°C)
Outdoor use
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II. GENERAL INFORMATION
1. CONSTRUCTION
Evaporator Spray Tube
Water ValveWater Supply Inlet
Transformer Box
Header
Junction Box
CPR Valve
Receiver Tank
Drier
Line Valve
Water Pump
Float SwitchPressure Switch
Cleaning Valve
Control Box
Expansion Valve
Hot Gas Valve
Compressor
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2. CONTROLLER BOARD
[a] SOLID-STATE CONTROL
1) A HOSHIZAKI exclusive solid-state control is employed in KM-2400SRF3 and
KM-2400SRH3 Stackable 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. Do not misconnect K3, K4 and K5,
because the same connector is used for the Thermistor and Float Switch.
K4 is not connected.
5. Always replace the whole board assembly when it goes bad.
6. Do not short out power supply to test for voltage.
1) Maximum Water Supply 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.
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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. To reset the safety, turn the power off and back on again.
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.
5) High Voltage Cut-out
The maximum allowable supply voltage of this icemaker is limited by the High Voltage
Cut-out.
If miswiring (especially on single phase 3 wire models) 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. The Control Board will signal this problem using 7
Beeps every 3 seconds.
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.
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The green LED’s 1-4 represent the corresponding relays and energize and sequence 5
seconds from initial startup as follows:
Sequence StepLED’s on Length:Min.Max.Avg.
1 Minute Fill CycleLED460 sec.
Harvest CycleLED1, 4, & 22 min.20 min.3-5 min.
Freeze CycleLED15 min.60 min.30-35 min.
Reverse Pump OutLED1, 3, & 210 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, low charge, or inefficient compressor.
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%.
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.
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
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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.
(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.