Troubleshooting a Walk-In Freezer

A walk-in freezer is commonly used in larger commercial operations, such as grocery stores,, large markets and restaurants. These walk-in freezers allow the company to store large quantities of their products in a way that are easy to access. They also allow sufficient space to load up and remove the frozen products efficiently.

There are a number of possible problems for walk-in freezers, but the most common is from a frozen evaporator coil. This is the most common service call that mechanics answer, and there are a number of different ways to troubleshoot this problem.

Troubleshooting questions and solutions:

1. Does the door close completely? If not, check to see that the door gaskets are in good condition, and that they seal properly.


2. Is there ice or snow hanging from the ceiling, or layered on the floor inside the freezer? This is likely the result of air and moisture entering the freezer. 


3. Is the evaporator drain pain frozen? If so, check the heater in the pan.


4. Is the drain line frozen? If so, the pipe heater may be broken and in need of repair.


5. Do the evaporator fans run? Melt the ice and turn the fans, and make sure the blades are the right size.


6. Is the defrost timer working? Make sure that it's correctly wired. Manually put it into defrost mode and see if the circuit kicks in and stays powered. Check the timer contacts and the wiring. If it does cycle into defrost, open the panels to the evaporator, check the amps and repair any that are not working.


7. Is the unit not cooling due to a short-cycling compressor? Turn off the freezer, and look around for leaks, while letting the gauges check for pressure problems. Repairing the leak should fix this problem. If there is no leak, check the pressure with the gauges.


8. Does the compressor run for a short time, then cycle off with the oil safety switch? Check the oil levels of the sight glass. Fill the oil to the proper level, and inspect it for leaks in the system.


9. Does the oil pump maintain oil pressure, but the safety switch keeps tripping? The switch may need to be replaced.


10. Does the oil pump maintain oil pressure? If not, the oil pump may be malfunctioning, or the compressor may be work out.