The good news is that it doesn't ultimately matter much whether you keep your freezer full or empty. The exception is if you live in an area where power outages are common: if that's you, you'll want to keep your freezer full to help keep foods cold longer when you lose electricity.
TLDR: full freezer takes more energy to initially cool, but less energy to maintain frozen. If you are constantly thawing and freezing your entire stock, keep it mostly empty. If you're freezing fairly long term, keep it full.
Freezer efficiency tip: Keep it full If your freezer isn't currently full to capacity, add jugs and bottles of water until it's full. A full freezer is more efficient and will stay cold longer if the power is out. Most of you probably already know this tip, but it's good to mention the basics for newcomers.
Freezer's work at their most efficient when at least 75% full. The less space available, the less the freezer has to do to keep the temperature down. a good thing. Overfilling the freezer can block air vents, restrict the flow of cold air, and overtax your refrigerator's condenser, which could lead to a burn out.
Ensure the freezer is not jammed-packed as it can limit air circulation, keeping it 70% to 85% full is recommended.
Filling your freezer to capacity makes it more energy-efficient by minimizing the amount of warm air that can enter it when you open the door. Also, the mass of the contents helps to recool the air.
Keep your freezer full, but not packed. Keeping your freezer around 75-80% full helps retain cold air. If the freezer is fully filled, food may block the internal air vents, making it harder to distribute cold air throughout the freezer.
OVERPACKING
If your freezer is not working, the first thing to check is if the shelves are packed too tightly. Overstuffed freezers can cause an airflow blockage, especially when the evaporator fan is blocked. If your freezer is not cold enough, try clearing off your freezer shelves.
What's the Right Deep Freezer Temperature? 0 degrees Fahrenheit or lower is the ideal deep freezer temperature for most foods. Food items stored at this temperature are safe and can be used indefinitely, although the taste and quality of some items may decrease if stored too long before you use them.
A freezer that remains unused for more than a year may develop some issues. To counteract this, consider running the freezer periodically, even if it's empty. This practice helps maintain an optimal internal temperature and prevents the compressor from becoming stagnant.
For Refrigerators and Freezers to maintain the proper temperature, the compressor will run much of the time. Refrigerators and Freezers have compressors that are designed to run 80% to 90% of the time.
Don't forget, a full freezer is more sustainable as it needs less cool air to circulate, meaning less power! If your freezer is only half full, we recommend filling it up with water bottles or ice packs to fill the gaps.
If there are small ice crystals, this shows that the food has lost its moisture. If the ice crystals are very large, this may indicate that the meat has thawed and refrozen, meaning that it is likely to spoil.
You see, freezers work best when they are full. This is because freezers expend most energy when they have to cool down the warm air that gets in when you open the door to take food out. A packed-to-the-brim freezer means there is less room for warm air to get in.
Their representative told us: “A freezer full of food should maintain its temperature better than an empty one”—with “lower temperature fluctuations when the door is opened.” As they explained, though: “[Y]ou also need to get that food cold in the first place, which will take a lot more energy than cooling air.”
On average, the life expectancy of a refrigerator-freezer or chest freezer is 16 years. Freezers typically last anywhere from 12 to 20 years. Along with gas and electric ranges, freezers tend to be the longest-lasting kitchen appliances. But that's not a guarantee!
Keeping the freezer nearly empty
A full freezer retains cold better than an empty one. When you open the door, the mass of frozen food will help keep in the cold, and the unit won't have to work as hard to cool empty space. But don't jam pack the freezer either; you need air to circulate.
One common hiccup is when the freezer only freezes at the bottom. The culprit? Poor air circulation.
A freezer will run more efficiently when full. This is because it doesn't have to work as hard to cool down the internal temperature. It is therefore cheaper to run a freezer that is full. Do old freezers use more electricity?
It's pretty easy to remember: Your freezer temperature should be set to a chilly 0° Fahrenheit or below (-18° Celsius or below). Food stored at 0° Fahrenheit or below is safe to eat indefinitely (although quality and taste may be compromised as time passes).
While a full freezer runs more efficiently than an empty one, overfilling it can potentially block the air vents. This in turn will restrict the air circulation and put added pressure on the motor and condenser.
Keep it stocked
A full fridge is a happy fridge because the thermal mass of its contents helps maintain the temperature (or in other words, the cold stuff helps keep it cold). In a full fridge, the compressor won't need to cycle on and off as much, which will extend the life of the compressor and reduce running costs.