Preventive Maintenance ( PM ) is the key to maximum running efficiency, less down time, and longer life out of an ice machine.
The primary items for an ice machine PM  check are as follows:

Clean and sanitize the water system.
Clean air filters on air-cooled models.
Check external filter system and change cartridges as needed.
Check inlet water valve screens.
Conduct bearing and auger inspection on extruded ice makers.
Conduct a visual inspection of components, controls, and wiring for oil spots, loose wires, loose fasteners, corrosion, etc.
Clean the bin interior and unit exterior.

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Clean and Sanitize

As ice forms on an ice machine evaporator plate, a separation occurs. Minerals separate from the water and form scale which sticks to the surfaces of the water system components. This scale will be more visible when the surfaces are dry. The color of the scale will vary due to the type of minerals in the local water supply. As an example, lime or calcium scale will be off white in color while iron scale will turn a rusty red color. Algae or slime growth may also occur in some locations. This is due to air or water-borne bacteria which can settle in the wet areas and grow.

Clean and Inspect

While you are waiting for the cleaning solution to do its job during the cleaning process, you can complete other steps in the PM check. Clean the condenser and/or air filter if included on the unit, and check the inlet water valve screen for restriction. Clean condenser fan blades.If the condenser coil is covered with grease, grime or dirt, use a non-corrosive cleaner and rinse thoroughly with water.  You may find it necessary to use a fin comb or brush on the coil fins. This is especially important on remote condenser units where

Flaker Bearing and Auger Inspection

Flakers produce ice on or inside an evaporator cylinder. The ice is broken away and extruded out of the cylinder by a gear motor-driven auger. Bearings allow the auger to rotate and maintain its positioning in the evaporator cylinder. Since the auger turns, bearing wear is eminent. A flaker bearing is a wear item. These bearings should be inspected per the manufacturers’ recommendations. the coil is subjected to outside elements.

Clean Exterior

The final step in the PM process is to clean the exterior. Use a soft cloth and a neutral cleaner to wipe down the stainless exterior of the unit and storage bin.