Your commercial dishwasher makes cleaning loads of dirty dishes easy for your establishment. However, you may notice it eventually has limescale, or a whitish film. Limescale isn't really lime, but a substance forms from build up of minerals in the water that sticks to the dishwasher. 

Signs of limescale commonly include a white film on dishes and lack of suds in soapy water. You should be able to remove the limescale yourself by following these tips.

Prepare to Clean The Dishwasher Limescale

To clean limescale, you need:

• white vinegar
• lemon juice
• your regular dish detergent
• drinking glass
• nylon scrub pad
• cream of tartar
• needle or pin
• baking soda or salt 

While natural methods remove mild limescale, severe deposits may require a commercial cleaner. Read your manual to determine the correct cleaning agents and methods, since some manufacturers often make recommendations. 

Test all cleaning products on a hidden area of the machine. To test for hard water, buy a titration kit from a cleaning chemical supplier. Sometimes, using the wrong detergent or a spilled rinse product can cause deposits on the outside of the dishwasher. Powdered detergent is more effective for removing the buildup.

Clean with Vinegar

Remove dishes and utensil holders from the machine. Moisten a scrub pad with vinegar or lemon juice, and wipe as much of the film as possible. Rub the vinegar or lemon juice on sprayer arms and racks using an old toothbrush or vegetable brush, let it sit several minutes, and scrub. Use a needle or pin to remove debris from holes.

 Avoid using too much vinegar, because the acid could possibly damage parts. To be safe, clean the unit with vinegar once or twice per month, and never mix it with other cleaners.

Fill a large glass or cup with two cups of vinegar, adding extra for tall tubs. Set the cup on the bottom rack, because the top sprayer will fill it full causing an overflow. which makes the cleaning more effective. 

Close the door, turn the cycle on "Normal" or "Regular", and let it complete the cycle. Leave the door open overnight to dissolve the lemon or vinegar smell inside the machine. Avoid using the high heat or sanitize cycles, which may push a steam through the sides, causing a vinegar smell. 

Use Cream of Tartar or Baking Soda

Scour the interior with baking soda or salt, and run a rinse cycle or use boiling water to rinse. Make a paste from cream of tartar and water, and rub it on the inside of the unit. Let the mixture stand about thirty minutes, scrub the surface with a damp rag, then urn the rinse cycle.

Contact a commercial cleaning service for more help.