Manufacturers classify ice machines by the type of ice a unit produces, such as cube, nugget or flake.
Operation varies, depending on the type of ice. Cube ice machines, sometimes referred to as batch ice makers, freeze water over a period of time. Within the cuber, or vertical evaporator, operators can choose from small, medium and large units. Cube
machines represent the most common type of ice maker because of their versatility. These units harvest and dispense clear, rhomboid-shaped cubes one at a time.
Flake and nugget machines produce ice continuously with no lag time between batches. These systems tend to use less water and electricity compared with cube machines.
Nugget continues to grow in popularity. Because it is 70 percent to 80 percent water, nugget ice tends to be easier to chew than other forms. Flake ice is even softer than the nugget type. Because of the extremely high water content, operators primarily use this ice for display purposes and with grab-and-go food, rather than in beverages.
A newer category of gourmet ice has emerged due to the growth in craft spirits. Some units in this category produce a large 60-gram cube that melts more slowly for use in exotic liquors that are spiced, aged or flavored.
In terms of capacity, ice machines produce between 500 to 3,300 pounds per day or 24-hour period. The most popular capacity is between 300 to 1,000 pounds per day. Operators frequently use smaller units as auxiliary ice machines, while hotels and convention centers use high-volume units.
Ice machines use one of four different condenser types. The most popular is the air-cooled version, which sits on the machine’s exterior. Air from the environment is drawn over the condenser to cool the refrigeration system.
Water-cooled systems draw water in from a separate chilled water loop to cool the unit. Because these units require separate plumbing hookups, they tend to be more common for larger operations, including schools or hospitals.
The third option is a remote version where the condenser is an auxiliary or separate unit placed on a roof top or in an area separate from the ice machine. A fourth condenser option has both the compressor and condenser located remotely. This removes both heat and noise from the kitchen and is ideal for front of house use. Small ice makers tend to be self-contained, while larger units are more likely to use remote condensers.
Ice machines generally measure 22, 30 or 48 inches wide, which allow operators to stack them on top of beverage dispensers. Modular units for use atop ice storage bins represent another option. Self-contained ice machines, also referred to as undercounter units, include built-in bins.
A newer feature in the ice machine world is the ability to produce ice and deliver it through a tube to a dispenser up to 75 feet away. This removes the heat, noise and bulk of the machine from the kitchen and provides easier access for cleaning.
Some models allow operators to flush more or less water through the system, which increases efficiency and reduces scale build up. It has become more common for manufacturers to treat plastic inside the food zone with an antibacterial coating. Auto cleaning systems connect to the unit for cleaning and sanitizing the evaporator.
Batch-type ice makers save on average about 1,200 kWh and 6,300 gallons of water per year. These units are approximately 15 percent more energy efficient and 23 percent more water efficient than traditional units. Continuous-type ice makers have average yearly savings of about 1,500 kWh and are on average 15 percent more energy efficient than other models.
A new ruling published by the U.S. Department of Energy in January 2015 sets stricter energy efficiency guidelines for all ice machines sold in the U.S. Effective January 2018, all ice machines must meet a minimum energy consumption rate.