Hoshizaki DKM-500BAH service manual Sequence of Operation

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B. Sequence of Operation

The steps in the sequence are as outlined below. When power is supplied, a 5 second delay occurs at startup. Note that the order of the LEDs from the outer edge of the board is 1, 4, 3, 2.

1. One Minute Fill Cycle

LED 4 is on. WV opens and the fill period begins. After 1 minute, the board checks for a closed F/S. If F/S is closed, the harvest cycle begins. If not, the unit will not start without adequate water in the sump. This serves as a low water safety to protect the water pump. WV will remain energized through additional 1 minute cycles until water enters the sump and F/S closes.

2. Initial Harvest Cycle

LEDs 1, 4, and 2 are on. WV remains open, Comp energizes, HGV opens, and harvest begins. As the evaporator warms, the thermistor located on the suction line checks for a 48°F (9°C) temperature. When 48°F (9°C) is reached, a 3.9 ksignal turns the harvest over to the adjustable harvest timer which is factory set for normal conditions. The timer has settings of 60, 90, 120, and 180 seconds (dip switch 1 & 2). When the harvest timer completes its count down, the harvest cycle is complete and the freeze cycle starts. The minimum total time allowed by the board for a complete harvest cycle is 2 minutes.

3. Freeze Cycle

LED 1 is on. Comp continues to run, PM and FMS energize, HGV and WV close and the freeze cycle starts. For the first 5 minutes the control board will not accept a signal from F/S. This 5 minute minimum freeze acts as a short cycle protection. At the end of 5 minutes, F/S assumes control. As ice builds on the evaporator the water level in the sump lowers. The freeze continues until F/S opens and terminates ice production.

4. Pump-Out Cycle

LEDs 1, 3, and 2 are on. Comp continues to run, HGV opens, and FMS de-energizes. PM stops for 2 seconds. SR energizes, restarting PM and taking water from the sump and forcing it to go through DV and down the drain. When the pump-out timer stops counting, the pump out is complete.

Pump out always occurs on the 2nd harvest after startup. Then, depending on the control board setting, pump out occurs every cycle, or every 2nd, 5th or 10th cycle (dip switch 5 & 6).

5. Normal Harvest Cycle

LEDs 1, 4, and 2 are on. Comp continues to run, HGV remains open and WV opens. As the evaporator warms, the thermistor reaches 48°F (9°C). The control board then receives the thermistor's 3.9 ksignal and starts the harvest timer. The water valve is open during harvest for a maximum of 6 minutes or the length of harvest, whichever is shorter. When the harvest timer completes its count down, the harvest cycle is complete and the next freeze cycle starts.

Note: The unit continues to cycle through 3, 4 and 5 sequence until the bin control is activated (within first 5 minutes of freeze) and shuts the unit down.

Legend: Comp–compressor; DV–Drain Valve; FMS–self-contained fan motor; F/S–float switch; HGV–hot gas valve; PM–pump motor; SR–Service Relay; WV–inlet water valve

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Contents DKM-500BAH Hoshizaki AMERICA, INC Contents Page DKM-500BAH SpecificationsDKM-500BAH II. General Information ConstructionSequence of Operation Cycle DKM-500BAH Sequence Flow Chart and Component OperationControl Board Control Board Layout Control Products E Control BoardControl Board Maximum Water Supply Period 6 minutes Harvest Backup Timer and Freeze TimerHigh Temperature Safety Low Water SafetyPM, SR, DV LED Lights and Audible Alarm SafetiesDefault Dip Switch Settings Controls and AdjustmentsHarvest Control Thermistor Pump-Out Timer dip switch 3 Harvest Timer dip switch 1Freeze Timer dip switch 9 Pump-Out Frequency Control dip switch 5Bin Control Machine Will Not Shut Off Bin Control TroubleshootingControl Board Check Procedure Machine Will Not StartService Switch SwitchesControl Board Replacement Control SwitchWash CirculateDKM-500BAH Wiring Diagram Timing Chart Page 110 Performance DataIV. Service Diagnosis Minute Diagnostic Procedure Ice Making Diagnostic ChartsNo Ice Production Problem Possible Cause Remedy Problem Possible Cause Remedy Evaporator is Frozen Up Abnormal Ice Low Ice ProductionDispensing OtherProblem Possible Cause Remedy Evacuation and Recharge R-404A Removal and Replacement of ComponentsService for Refrigerant Lines Refrigerant RecoveryBrazing Removal and Replacement of CompressorRemoval and Replacement of Drier Removal and Replacement of Hot Gas Valve Removal and Replacement of Expansion ValveRemoval and Replacement of Evaporator Removal and Replacement of Condenser Removal and Replacement of Fan Motor Removal and Replacement of ThermistorRemoval and Replacement of Pump Motor Removal and Replacement of Inlet Water ValveRemoval and Replacement of Gear Motor Removal and Replacement of Spray TubesRemoval and Replacement of Solenoid Removal and Replacement of Dispense SwitchCleaning Instructions VI. Cleaning and Maintenance InstructionsCleaning Procedure Icemaker Sanitizing Procedure Icemaker Sanitizing Procedure Bin Cleaning Procedure BinAir Filters Maintenance InstructionsPreparing the Icemaker for Long Storage Exterior Panels

DKM-500BAH specifications

The Hoshizaki DKM-500BAH is a high-performing ice maker renowned in the food service industry for its reliability and efficiency. This unit excels in producing crescent-style ice, which is highly sought after for its ability to chill beverages effectively while minimizing dilution. The Hoshizaki reputation for quality is well-reflected in the DKM-500BAH, making it a popular choice in restaurants, bars, and other establishments that demand high ice production capacity.

One of the standout features of the DKM-500BAH is its impressive ice production capability. This model has the capacity to produce up to 500 pounds of ice per day, ensuring that businesses with high-volume demands can meet their needs without interruption. The unit operates on a refrigerant system designed for optimal energy efficiency, which can lower operating costs and contribute to sustainability goals.

The DKM-500BAH utilizes advanced technology, including Hoshizaki's patented ice-making mechanism. This system features a stainless steel evaporator that enhances durability and ice quality. The crescent-shaped ice it produces has a slower melt rate, making it perfect for restaurants and bars that focus on customer experience. Additionally, the unit is equipped with a cycle control that ensures ice is produced consistently.

Another critical aspect of the DKM-500BAH is its user-friendly design. It features a front-facing control panel that allows for easy monitoring and adjustment of settings. A built-in diagnostics system alerts users to potential issues, enabling prompt maintenance and reducing downtime. The removable air filter is another convenience, making it simple to clean and maintain the unit’s efficiency.

Moreover, the construction of the DKM-500BAH is noteworthy. It features a corrosion-resistant stainless steel exterior that ensures longevity and maintains hygiene standards. The unit also has an insulated storage bin that holds up to 250 pounds of ice, making it an efficient solution for busy settings.

In summary, the Hoshizaki DKM-500BAH is a robust ice maker that combines high production capacity, advanced technology, and user-friendly features. Its build quality and efficient performance position it as a leader in the commercial ice-making market, making it an ideal investment for establishments requiring reliable ice supply.