To ensure food products are fresh and preserved, a commercial freezer needs to run at optimal temperatures. In some cases, this may cause a build-up of frost on evaporator coils which can then result in spoilt food, reduced efficiency, high energy bills and costly repairs.
Although many modern fridge freezers can self-defrost, there is still a chance you might have to face the issue of defrosting at least once a year, when a layer of ice has become thicker than a quarter of an inch.
These are 3 of the best tips to defrosting a commercial freezer.
1) Preventing Frost Build-Up
If you have a walk-in freezer or remote cabinets, you should always enter and exit the freezer as quickly as possible, while avoiding leaving the doors open for longer than necessary. This will minimise the amount of warm air entering the unit, which can cause the compressor to keep running.
If your freezer needs to be restocked or repacked, it’s best to switch off the refrigeration system as well as fan motors, to ensure that there’s no air turbulence or negative pressure, encouraging warmer air to rush inside the freezer.
2) Auto-Defrost Features
Auto-defrost systems can be common in most commercial freezer units, particularly where temperatures need to be maintained at or below freezing. This feature will automatically shut down the refrigeration system but it’s important to note that the type of auto-defrost control on a commercial freezer will depend on a number of things; the freezer model, the products stored, the running temperature and how often the doors are opened.
Depending on your own requirements, it’s important to know which types of auto-defrost may be best for you.
• A normal compressor off-cycle is an option that can be enough to keep the condenser coils frost-free.
• Some freezer units may have a defrost timer that shuts off the compressor, while keeping the evaporator fans running, allowing room temperature air to melt the frost.
• If you have walk-in freezers with extremely low temperatures, a timer will shut off the evaporator fans before defrost heaters or elements turn on to melt any frost off the coil surfaces and warm the drain pan. The evaporator fans will then only turn on, once the refrigeration system has cooled the coils down.
3) Maintaining Defrost Cycles
Commercial kitchens can be a humid place and since cooking and cleaning dishes tend to generate a lot of steam, moisture can inevitably find its way into your freezer, causing condensation. When condensation happens on the freezer’s evaporator coils, it turns into frost.
A commercial freezer should have up to three to four defrost cycles per day and should be set for specific times. It is imperative to ensure the defrost cycle kicks in when there’s enough frost build-up, while the heaters should be able to defrost the coils within 15-20 minutes. If your freezer does have an automatic defrost control, the equipment needs to be regularly checked and serviced by professionals. Be sure to at least check once a week that the coils are free of ice and that water can exit freely down the drain line.
If your freezer seems to be struggling to reach the correct temperature settings and can’t manage an adequate defrost cycle however, you may have to force shut down your refrigeration system to allow it to defrost properly or call professional refrigeration experts. Extreme levels of frost will put a burden on the refrigeration system and cause it to fail. Defrost cycles are designed to avoid problems caused by the buildup of ice.
John Bossy Refrigeration has been servicing Adelaide’s hospitality and catering industry for more than 30 years. If you’re in the market for a new catering freezer, catering fridge or service repairs, our team of fully trained service technicians are here to help. Contact us today for a free quote and to find out more about what we can do for you.