Freezer Not Freezing

A freezer that isn't freezing properly is most commonly caused by dirty condenser coils that can't shed heat efficiently, though a failed evaporator fan, a defrost system fault, or a compressor issue can also be the reason. Because frozen food safety depends on consistent temperature, it's worth checking the cause quickly. 

Common Causes 

• Dirty condenser coils. These coils release heat from the freezer's cooling system into the room. When covered in dust, they trap heat instead, making it harder for the unit to reach and hold freezing temperatures. This is often the first thing worth checking, since it costs nothing to clean and rules out the simplest cause. 
• Evaporator fan failure. This fan circulates cold air throughout the freezer compartment. If the motor seizes or the blade gets jammed by ice, cold air stops moving around, leaving some areas warm even though the compressor is still running in the background. A grinding or clicking noise is often the first clue something's wrong with the fan itself. 
• Defrost system fault. Freezers periodically melt built-up frost to keep airflow clear. If the defrost heater, timer, or thermostat that controls this cycle fails, ice can build up around the coils and block airflow entirely, which gradually makes the whole unit less effective at holding temperature. 
• Compressor failure. The compressor is what actually cools the refrigerant that keeps the freezer cold. If it fails or loses efficiency, the freezer may run constantly without ever reaching a safe temperature, and you may notice the unit sounds like it's working harder than usual. 
• Thermostat issue. The thermostat monitors internal temperature and tells the system when to run. A faulty sensor can cause the compressor to shut off too early, before the freezer is actually cold enough, which can make the problem look worse than it actually is. 

When to DIY vs. Call a Pro 

You can safely clean visible condenser coils, make sure the freezer isn't packed so full that it blocks airflow, and confirm the door is sealing and closing fully. Diagnosing a fan motor, defrost system, or compressor issue involves testing electrical and sealed refrigerant components, which needs a licensed technician rather than a home fix. 

FAQ 

How can I tell if it's the defrost system rather than the compressor? 

A heavy buildup of frost or ice around the back panel inside the freezer usually points to a defrost system fault. A freezer that runs constantly but never gets cold, with little frost buildup, points more toward the compressor or thermostat instead. 

Is my food still safe if the freezer is only partly cold? 

Food that has started to thaw and refreeze can lose quality, and depending on how warm it got, may not be safe to eat. If you're unsure, check the temperature with a thermometer rather than relying on touch or appearance alone. 

Why does my freezer have ice buildup on the walls? 

As long as your freezer is “FROST FREE”, this is a classic sign of a defrost system fault, since the automatic defrost cycle that's supposed to clear this buildup isn't running properly. It's one of the more common causes on this list, and it tends to get worse the longer it goes unaddressed. 

Can I speed things along by leaving the freezer door open? 

No, leaving the door open lets warm, humid air in and can make ice buildup worse, which puts more strain on a system that's already struggling. It's better to check the basics, like the door seal and coils, and call a technician if the problem continues rather than trying to force the unit to catch up. 

Is it worth repairing a freezer, or should I just replace it? 

For common issues like coils, fans, or defrost parts, repair is usually the more affordable option, especially compared to the cost of a new unit plus delivery and installation. A technician can confirm the actual fault and give you a straight comparison of repair versus replacement cost before you decide. 

If your freezer is still not holding temperature after checking the basics, Boreal can diagnose the issue and repair it, backed by a 90-day warranty on parts and labour.