Which Direction of Air Flow Is Used for a Walk-In Freezer Condensing Unit?

Refrigeration Systems

• A walk-in freezer unit uses many of the same components found in a refrigeration system. These components include condensers, evaporator coils, compressors and expansion devices. Ultimately, a walk-in freezer system works to remove heat from the inside freezer compartment and release it as gas into the outside air. Heat enters in through the compressor, which sits inside the walk-in freezer unit. Heat exits the system through the condenser component, which sits on the exterior or outside portion of a walk-in freezer unit.

Heat Transfer Process

• The heat transfer process for a walk-in freezer involves moving refrigerant liquids from one side of the unit to another. An evaporator sits inside the freezer compartment where heat absorbs into the unit’s refrigerant liquid. The refrigerant liquid then moves into the compressor, which squeezes or compresses the absorbed heat into the refrigerant liquid. This process places the refrigerant liquid in a high-pressure state. This high-pressure state allows heat to be extracted in the form of gases. From this point, the gases enter the condenser coils, where they change back into liquid form. Within this conversion process, the condenser coils release heat gases into the outside air. Refrigerant pressures decrease as liquids move through the expansion valve and on back to the evaporator.

Air Flows

• Air flow plays an active role in helping to regulate temperature levels throughout a walk-in freezer’s refrigeration system. The system as a whole suctions air from the freezer interior and out through the back of the unit. Air flows over the condenser component help to extract heat from the coils. Air movements across the condenser coils also help to cool it down. Since the condenser squeezes heat out of refrigerant liquids, it tends to get fairly hot. To prevent overheating, air flows from the evaporator side of the condenser and towards its exterior side. In effect, air flows across the condenser component help to regulate the temperature of the refrigerant as it moves into and out of the condenser.

Air Flow Effects

• Poor air flows across a condenser unit component can cause ice or frost formations to develop in areas where refrigerant materials enter and leave the condenser. As heat gas releases occur at condenser unit coils, these areas often develop condensation as refrigerant liquids flow through the coils. If air flows fail to move across the evaporator line that exits the condenser, ice or frost can form. If left unattended, a freezer’s refrigeration system may show signs of lost cooling capacity.