Deep fryers should be cleaned regularly to ensure that food cooked in them is safe to eat and doesn't develop an unpleasant taste. Plus, keeping your fryer clean will ensure it heats oil quickly and efficiently, and therefore uses less energy. You should aim to do a full clean of a fryer once each month if the appliance is used heavily. However, oil should be changed far more frequently. When the oil develops a dark colour, changes in consistency, or develops an unusual odour, it's time for an oil change. The rate at which this is necessary depends on the frequency of use. Remember to always skim off any floating debris from the oil at the end of every service.

To do a full clean of a commercial deep fryer, turn the appliance off, let it cool completely, then drain the oil. Wipe the interior with clean cloths or paper towels. Fill the tank with water and add an appropriate fryer cleaner which will work to loosen the grease. Turn the fryer on to heat the water until it reaches a boil which should be maintained for thirty minutes. Turn the fryer off and let the water cool completely before draining it. As the water drains you can use a scrubbing brush on the fryer interior to remove any stubborn dirt. Flush the fryer at least once with clean water until the cleaning solution has been completely removed, then allow it to dry fully.