IV. SERVICE DIAGNOSIS

1. DIAGNOSTIC PROCEDURE

The diagnostic procedure is basically a sequence check which can be used at unit start- up or for system diagnosis. Using this check out procedure will allow you to diagnose electrical system and component failures in approximately 10 minutes under normal operating conditions of 70°F (21°C) or warmer air and 50°F (10°C) or warmer water temperatures. Before conducting a 10 minute checkout, check for correct installation, proper voltage per unit nameplate and adequate water supply. As you go through the procedure, check to assure the components energize and de-energize correctly. If not, those components and controls are suspect.

1)Turn power off and access the control box. Clear any ice from the bin control actuator located in the bin.

2)Turn power on and place the control switch in the “ICE” position. A 5 second delay occurs. The “POWER OK” LED on the control board comes on. If the “POWER OK” LED is flashing (indicating a full bin), check the bin control. See “II. 5. [b] BIN CONTROL CHECK PROCEDURE”.

3)One Minute Fill Cycle – The inlet water valve is energized. After 1 minute, the control board checks the float switch. If the float switch is closed, the unit cycles to harvest. If closed, continue to step 4. If the float switch is open, the unit repeats the 1 minute fill cycle until water enters and the float switch closes (low water safety protection during initial start up and at the end of each harvest). Diagnosis: If the water valve does not open, check for no supply voltage at water valve terminals, bad coil, or plugged screen or external filter (no water flow). If unit fails to start harvest, check for open float switch or bad 1 minute timer in board.

4)Initial Harvest Cycle – The inlet water valve remains energized, contactor coil energizes to start the compressor (and fan motor on a remote condenser unit), and the hot gas valve energizes. The evaporator warms and the thermistor senses 48 °F (9°C). The control board then receives the thermistor's 3.9 kΩ signal and turns operation of harvest over to the harvest timer. The timer completes counting (1 to 3 minutes). The unit then cycles to freeze. Diagnosis: Check if compressor is running, hot gas valve is open, water valve still open. Average harvest cycle at factory setting is 2 to 3 minutes. How long does initial harvest last? 1.5 minutes after initial harvest begins, touch the compressor discharge line. Is it hot? If not check refrigerant pressures and compressor operation. If it is hot, touch the inlet line to the evaporator. Is it hot? If it is hot and the freeze cycle is not starting, check the harvest timer adjustment, the thermistor for open circuit, the discharge line temperature, compressor efficiency, and if the hot gas valve is fully open.

5)Freeze Cycle – The compressor remains energized, pump motor, (line valve if applicable), and fan motor energize. The inlet water valve and hot gas valve de- energize. The unit is held in freeze by a 5 minute short cycle protection timer which

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Hoshizaki KM-260BWH, KM-260BAH, KM-201BAH, KM-201BWH service manual IV. Service Diagnosis Diagnostic Procedure

KM-201BWH, KM-260BWH, KM-201BAH, KM-260BAH specifications

The Hoshizaki KM-260BAH, KM-201BAH, KM-201BWH, and KM-260BWH are state-of-the-art ice machines designed for commercial use, demonstrating Hoshizaki's commitment to quality and innovation in the foodservice industry.

The KM-260BAH and KM-260BWH models are known for their impressive production capabilities, yielding up to 260 pounds of crescent ice daily. This ice type not only looks appealing but also has excellent cooling properties, making it a favorite in bars and restaurants. The KM-201BAH and KM-201BWH models produce up to 201 pounds of ice per day, making them ideal for establishments with moderate ice needs.

One of the standout features of these machines is the advanced air-cooled technology, which ensures optimal efficiency and reliability. The air-cooled condenser minimizes water usage, reducing operational costs while delivering consistent performance. Both BM-260 and KM-201 series models are equipped with a highly efficient refrigeration system, promoting rapid ice production even in warm environments.

The KM-260BAH and KM-260BWH models utilize a durable stainless steel exterior, providing not only a sleek appearance but also resistance to corrosion, ensuring longevity in demanding kitchen environments. The interior of these machines is designed with ease of cleaning in mind; a removable front panel allows quick access for maintenance, making service less time-consuming.

In terms of energy efficiency, these Hoshizaki ice machines meet Energy Star standards, offering reduced energy consumption and lower utility bills. The smart design also minimizes noise, creating a more pleasant atmosphere in bustling kitchens.

Another important characteristic of the KM-201BAH and KM-201BWH models is their flexible installation options, allowing users to adapt the machine to their space effortlessly. Additionally, the optional built-in storage bin can be paired seamlessly for enhanced convenience.

These ice machines also come with Hoshizaki's distinctive EverCheck alert system. This technology monitors the machine's operation, notifying operators of any necessary maintenance or issues before they become significant problems.

Overall, the Hoshizaki KM-260BAH, KM-201BAH, KM-201BWH, and KM-260BWH models showcase cutting-edge technology, energy efficiency, and user-friendly features, making them an excellent choice for any business in need of a reliable ice solution. Their focus on durability and performance positions them as a benchmark in the commercial ice machine sector, ensuring a consistent supply of high-quality ice.