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How to Delime a Commercial Dishwasher

Picture - How to Delime a Commercial Dishwasher

A dishwasher is a vital part of a commercial kitchen, making cleanup as easy as possible. Your customers may forgive an overcooked steak, but they probably won’t forgive dirty dishes. While a dishmachine or warewasher should keep items sparkling clean, eventually lime buildup may form inside the unit. This can cause mineral deposits to form on dishes, glasses and silverware.

We've talked about the importance of water filtration and the damaging effects of water hardness. While it's advisable to deal with water hardness using a softening system rather than repeated deliming cycles because the acid can erode a machine over time, you should occasionally delime if you notice abundant scale buildup. Here are some easy steps for deliming a commercial dishwasher.

• Step 1. Find the right cleaner - If the dishmachine uses chemical sanitizers like chlorine, iodine, or quaternary ammonia, consult a technician or an owner's manual to verify chemicals used for deliming. Mixing chemicals can create a noxious gas or acid which could be harmful to humans or damage your machine.

• Step 2. Drain the tank and fill with fresh water - Even if the machine has an automatic delime cycle, you may have to manually drain the tank and fill with fresh water before adding the deliming agent. Check out the owner's manuals to learn more about your model.

• Step 3. Add deliming solution - After filling the machine with fresh water, add the correct amount of deliming solution as recommended by the chemical manufacturer.

• Step 4. Run the machine - Close the door and run the machine for the time recommended by the manufacturer’s instructions. Some machines allow you to disconnect the timing mechanism and run the machine indefinitely. Others may require that you run multiple cycles. Check your owner's manual to see which is required.

• Step 5. Inspect the inside - After the cycle, inspect the inside of the machine. If it's not delimed, cycle again, following the deliming solution’s instructions.

• Step 6. Remove residue - If the machine is delimed, drain and refill the machine. Run for 10 minutes to remove residual deliming solution.

• Step 7. Drain and refill - Once the residual solution is gone, drain and refill the machine.

Please contact a local authorized service agent who can help with these specific units and all your commercial kitchen equipment needs.