Your restaurant or diner or even a retail store that sells chilled items will need a commercial refrigeration unit, not just a large unit meant for residential homes. This will ensure that fresh food items are kept safe in an antibacterial setting and allow for easy access to items by your customers. This type of unit is usually more expensive than a residential refrigerator, so it's important to regularly employ refrigeration service maintenance. Note a few tip for doing this on your own so you can ensure a long life from of your refrigeration unit.
Check the fan blades
It's good to check the fan blades for what are called stress fractures. These would be hairline cracks in the blades. If these are left unchecked, the blade itself can easily split. The hairline cracks also don't allow the blades to circulate air so easily; in turn, your refrigeration unit is working harder than it should in order to move cold air through the unit. If the fan blades are cracked in any way, be sure you replace them. You can also tighten the screws that hold the fan blades in place when you perform a visual inspection, to help keep the blades moving properly and keep them from becoming unbalanced.
If your commercial refrigerator doesn't defrost properly, this can allow frost to build up inside and also along the fan blades and other parts. It's good to check the defrost heaters regularly; use a voltage meter to ensure they're getting proper power so they don't slow down or fail to produce enough heat to keep your unit defrosted. Check the wiring around the heater for any bare or frayed areas; the heat produced by the heater itself can often damage the outer, protective casing of wiring, allowing it to become frayed. This puts your unit at risk for an electrical fire, so inspect that wiring carefully and regularly.
Empty the drain pan and inspect the hoses
As your refrigeration unit removes moisture from the unit, it will drain into a pan under the unit. You need to inspect this pan and empty it when needed, and inspect the hose or hoses connected to it. Be sure they're not crimped or bent and don't have any debris at the opening of the hose. If there is dirt, dust, hair and other such obstacles, this can allow the condensation from the refrigeration unit to get clogged and back up into the refrigerator itself.