5.Removal and Replacement of Expansion Valve

IMPORTANT

Sometimes moisture in the refrigerant circuit exceeds the drier capacity and freezes up at the expansion valve. Always install a new drier every time the sealed refrigeration system is opened. Do not replace the drier until after all other repairs or replacement have been made.

1)Unplug the icemaker.

2)Remove the panels.

3)Recover the refrigerant and store it in an approved container, if required by an applicable law.

4)Remove the expansion valve bulb at the evaporator outlet.

5)Remove the expansion valve cover, and remove the expansion valve using brazing equipment.

6)Braze the new expansion valve with nitrogen gas flowing at the pressure of 3-4 PSIG.

WARNING

Always protect the valve body by using a damp cloth to prevent the valve from overheating. Do not braze with the valve body exceeding 250°F.

7)Install the new drier.

8)Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.

9)Evacuate the system. Charge it with refrigerant. See the nameplate for the required refrigerant charge and type.

10)Attach the bulb to the suction line. Be sure to secure the bulb using a band and to insulate it.

11)Place the expansion valve cover in position.

12)Replace the panels in their correct position.

13)Plug in the icemaker.

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Hoshizaki F-450MAH-C service manual Removal and Replacement of Expansion Valve

F-450MAH-C, F-450MAH specifications

Hoshizaki F-450MAH and F-450MAH-C are advanced ice machine models designed for commercial use, ensuring high efficiency and reliability in providing ice for a variety of foodservice and hospitality applications. These models are recognized for their streamlined operation and innovative technology, making them a preferred choice for many establishments.

One of the standout features of the Hoshizaki F-450MAH is its impressive ice production capacity. The machine can produce up to 525 pounds of crescent cube ice daily, meeting the high demands of busy restaurants, bars, hotels, and catering services. The ice produced is not only uniform in size but is also perfect for mixed drinks, chilling beverages, and food display applications.

The F-450MAH and its counterpart, the F-450MAH-C, are equipped with an advanced water-cooled condenser, optimizing performance even in challenging environments. This technology allows the machines to operate efficiently, minimizing energy consumption and enhancing overall performance. Additionally, these models feature a self-cleaning function that reduces maintenance time and improves hygiene by automatically flushing water lines and purging scale buildup.

Hoshizaki prioritizes durability and reliability in its designs, and the F-450MAH is no exception. The machine is constructed from high-quality stainless steel, ensuring resistance to corrosion and easy cleaning. Furthermore, the interior of the ice bin is designed to be easy to access, allowing quick retrieval of ice while maintaining optimal hygiene standards.

In terms of usability, the F-450MAH and F-450MAH-C come with a user-friendly digital control panel that provides real-time information on ice production and machine status. Operators can easily monitor performance and make adjustments as necessary, enhancing operational efficiency.

The Hoshizaki F-450MAH-C variant is tailored for those in need of a modular unit. It is designed to be stacked with compatible storage bins or dispensers, offering flexibility in installation and ice storage solutions. This modularity allows businesses to customize their ice-making operations according to specific needs while maximizing space.

In summary, the Hoshizaki F-450MAH and F-450MAH-C are exceptional ice machines that combine high production capacity, advanced technologies, and robust construction. These models offer an excellent solution for businesses in the foodservice industry, ensuring a consistent supply of high-quality ice while reducing operational costs and maintenance efforts. With their reliable performance and user-friendly features, they are regarded as a top choice in the commercial ice machine market.