Why Walk-In Coolers Freeze Up

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A walk-in cooler is designed to keep your products cold — not frozen. But when ice starts forming on walls, floors, coils, or even food items, it’s a clear sign something isn’t working correctly. Frost buildup and ice accumulation can affect cooling efficiency, increase energy costs, and eventually lead to system failure if ignored.

At Buffo’s Refrigeration, we help restaurants, grocery stores, and foodservice facilities across Nevada diagnose and fix walk-in cooler problems before they turn into expensive repairs. Here’s why walk-in coolers freeze up and what you can do to prevent it.

Warm Air Leaks into the Cooler

One of the most common causes of ice buildup is warm, moist air entering the cooler. When this humid air meets cold surfaces, condensation forms and quickly freezes.

Common causes include damaged or worn door gaskets, doors left open for extended periods, cracked seals, or poor insulation.

Solution: Inspect door gaskets regularly and replace them if they’re cracked, loose, or no longer sealing properly. Make sure employees close doors completely, and consider installing strip curtains to reduce air infiltration during busy hours.

Poor Airflow Around the Evaporator Coils

Your walk-in cooler relies on consistent airflow to circulate cold air evenly. When airflow is blocked — either by overstocking or improper placement of products — the evaporator coil may get too cold and begin to freeze over.

Solution: Keep at least 4–6 inches of space between products and walls. Avoid blocking air vents or evaporator fans, and schedule regular commercial refrigeration maintenance to clean fans and check airflow.

Thermostat or Sensor Issues

If your thermostat or temperature sensor is malfunctioning, your cooler might run longer than necessary — dropping temperatures below ideal levels and causing ice to form.

Solution: Have a refrigeration technician test and calibrate your thermostat and temperature controls. The ideal walk-in cooler temperature range is 35°F to 38°F.

Dirty or Blocked Coils

When evaporator or condenser coils are dirty, heat transfer becomes inefficient. The system compensates by running longer, which can cause excessive frost or ice buildup on coils and nearby surfaces.

Solution: Schedule professional coil cleaning at least twice a year to keep your system running efficiently and prevent freezing issues.

Faulty or Incomplete Defrost Cycle

Walk-in coolers are designed to go through automatic defrost cycles to melt away small amounts of ice that naturally form on the coils. If the defrost timer, heater, or sensor fails, ice can accumulate rapidly.

Solution: A professional technician should inspect your defrost system to ensure it’s cycling correctly and that heaters and sensors are functioning properly.

Low Refrigerant Levels

Low refrigerant levels can cause the evaporator coil to get too cold, leading to frost or ice buildup. This often happens due to leaks or improper maintenance.

Solution: Contact a commercial refrigeration repair company immediately to check refrigerant levels. Only certified technicians should handle refrigerant repairs or refills.

Excess Humidity in the Environment

High humidity levels — common in Nevada’s summers — can cause moisture to enter your cooler and freeze when it contacts cold surfaces. This is especially likely in kitchens or warehouses without proper ventilation.

Solution: Keep doors closed as much as possible, ensure seals are tight, and consider using a dehumidifier if your facility has persistent humidity problems.

Why Ice Buildup Is a Serious Problem

Even a small amount of ice in your cooler can lead to major issues, including increased energy consumption, reduced cooling efficiency, strain on compressors and fans, water damage when ice melts, and food safety risks from inconsistent temperatures.

Ignoring ice buildup can shorten your system’s lifespan and lead to unexpected downtime.

Prevent Freezing with Routine Maintenance

The best way to stop ice problems before they start is through preventative maintenance. Regular inspections, coil cleanings, and defrost system checks keep your cooler running efficiently and ice-free.

At Buffo’s Refrigeration, we specialize in walk-in cooler maintenance, repair, and installation for restaurants, grocery stores, and foodservice businesses throughout Nevada. Our technicians ensure your system operates at peak performance — saving you time, energy, and money.

Schedule Service Today

If your walk-in cooler is freezing up or showing signs of ice buildup, don’t wait for the problem to get worse. Contact Buffo’s Refrigeration today to schedule service or request a free consultation. We proudly serve Nevada and surrounding areas with dependable commercial refrigeration repair, maintenance, and emergency service.

📞Call Us For A Free Quote 775-782-8204 | Buffos-Refrigeration.com

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Call Us For A Free Quote 775-782-8204 | Buffos-Refrigeration.com