If you have a restaurant, then you know that you need to take food safety seriously. That means keeping the cold stuff cold and the hot stuff hot. In order to make sure that your cold stuff stays cold enough, you are going to need to have a variety of coolers. That can include a large freezer to keep things completely frozen or a walk-in cooler that will let you keep refrigerated stuff under 40 F. You may also need to have coolers under prep stations so that you can keep a small number of ingredients right at hand to work with. In order to keep your food at safe temperatures, make sure that you maintain the coolers so that they will continue to work.
Clean the Evaporator Fans
The evaporators have coils and fans that keep the freezer nice and cold. However, they can get all kinds of gunk and buildup on them. All that buildup will make the evaporator have to work harder to keep things cool. If you clean the evaporator equipment off a few times a year, then that buildup should be gone and the system will work better. You won't have to worry about the evaporator burning itself out or costing you more money. When you clean the coils and fan blades off, make sure that nothing is open in the cooler, or clear the cooler out altogether for a deep clean.
Check the Hinges and Gaskets
Also, make sure that things like the hinges and gaskets are tight and not falling off. The gaskets run around the door and keep the door sealed tightly to the body of the freezer. That keeps the cold air in the cooler, which helps to maintain the appropriate temperature. If the hinges are loose, the door won't seal correctly and cold air will be able to leak out, which puts the food at risk for warming up and staying warm.
If you notice that any of your coolers or freezers no longer work the way that they should, call a commercial refrigeration company to come in and look at them. Even if you do all kinds of regular maintenance, your cooler may still not work as well as it could. Having a service technician come in and check it out will ensure that you aren't putting your customers at risk. And if your cooler really is unrepairable, you might want to consider replacement with a used stainless steel three door freezer.