2. Brazing

WARNING

•R-404A itself is not flammable at atmospheric pressure and temperatures up to

176°F (80°C).

•R-404A itself is not explosive or poisonous. However, when exposed to high temperatures (open flames), R-404A can be decomposed to form hydrofluoric acid and carbonyl fluoride both of which are hazardous.

•Do not use silver alloy or copper alloy containing arsenic.

1)Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.

Note: Because the pipes in the evaporator case are specially coated to resist corrosion, it is important to make connections outside the evaporator case when possible. If it is necessary to braze inside the evaporator case, use sandpaper to remove the coating from the brazing connections before unbrazing the components.

NOTICE

•Always install a new drier every time the sealed refrigeration system is opened.

•Do not replace the drier until after all other repair or replacement has been made.

Install the new drier with the arrow on the drier in the direction of the refrigerant flow.

•When brazing, protect the drier by using a wet cloth to prevent the drier from overheating. Do not allow the drier to exceed 250°F (121°C).

2)Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). Do not use R-404A as a mixture with pressurized air for leak testing.

3.Evacuation and Recharge (R-404A)

1)Attach a vacuum pump to the system. Be sure to connect the charging hoses to both high and low-side refrigerant access valves.

IMPORTANT

The vacuum level and vacuum pump may be the same as those for current refrigerants. However, the rubber hose and gauge manifold to be used for evacuation and refrigerant charge should be exclusively for POE oils.

2)Turn on the vacuum pump. Open the gauge manifold valves. Never allow the oil in the vacuum pump to flow backwards.

3)Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends on pump capacity.

4)Close the low-side valve and high-side valve on the gauge manifold.

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Hoshizaki MRH KM-901MAH, MWH KM-515MAH, MRH/3, MWH(-M), MRH KM-600MAH KM-650MAH Brazing, Evacuation and Recharge R-404A
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KM-320MAH, MRH KM-600MAH KM-650MAH, MWH(-M), MRH KM-901MAH, MRH/3 specifications

Hoshizaki, a leading manufacturer in the food service equipment sector, offers a diverse range of ice-making machines that excel in efficiency, durability, and innovative technology. Among the notable models are the Hoshizaki MWH KM-515MAH, MWH(-M), MRH KM-901MAH, MRH KM-600MAH, KM-650MAH, and KM-320MAH. Each model brings unique features designed to meet varying commercial ice production needs.

The Hoshizaki MWH KM-515MAH is particularly recognized for its high ice production capacity, generating up to 515 pounds of ice per day. This model incorporates advanced technology that ensures consistent ice quality and purity. The MWH(-M) variant often includes modifications to suit specific operational environments, ensuring reliability in diverse settings.

Similarly, the MRH KM-901MAH stands out with its ability to produce a staggering 901 pounds of ice per day, making it ideal for high-volume establishments. This model is equipped with Hoshizaki's unique "cubelet" technology, producing a soft, chewable ice perfect for beverages. It also features a robust stainless steel construction, enhancing its durability and resistance to corrosion.

The MRH KM-600MAH offers 600 pounds of daily ice output, while the KM-650MAH enhances that capacity to 650 pounds. Both machines prioritize energy efficiency and come with built-in energy-saving modes. These models feature advanced ice sensing technology that monitors production levels to optimize energy consumption and reduce waste.

On the other hand, the KM-320MAH is designed for smaller establishments, with a daily ice production rate of 320 pounds. Despite its smaller footprint, it maintains high production efficiency and is equipped with features like a built-in storage bin, saving space while ensuring a reliable ice supply.

Across these models, Hoshizaki employs various technologies, including air-cooled and water-cooled systems, offering flexibility depending on installation requirements. The ice machines are designed with user-friendly controls and features like self-cleaning capabilities, making maintenance straightforward and less time-consuming.

In summary, Hoshizaki's ice machines, including the MWH KM-515MAH, MRH KM-901MAH, and others, deliver exceptional ice production, durability, and efficiency tailored to meet the demands of any commercial kitchen or service establishment. With a commitment to quality, Hoshizaki continues to be a trusted choice for businesses needing reliable ice-making solutions.
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