There’s nothing worse than waking up in the morning and heading downstairs, only to find that your freezer door was left ajar. I mean….what “really” happens if you leave the freezer open overnight? What if it was left open for 12 hours? Or just two hours? Will the food in there be ok? And what do you do after the freezer door was left open?
How Long Can You Leave the Freezer Door Open?
You can leave your freezer door open for around 2 hours without the contents or the freezer itself being negatively impacted. Longer than this, and you’ll need to discard the contents, unfortunately.
Is Food OK If the Freezer Is Left Open?
When it comes to food and how safe it now is after leaving the freezer open, we would always recommend erring on the side of caution – especially for meat and fish products.
The cold temperature of a freezer helps to preserve food whilst keeping away bacteria and mould. As soon as the temperature begins to rise, bacteria can begin to form on the surface of your food. If your freezer has been open overnight, for several hours, then there is a huge risk bacteria has already formed.
You could go through each item of food to try and determine if mould has begun to form but, in most cases, it’s worth discarding items such as meat, fish and dairy products.
Ice creams, some fruits and vegetables, bread and sugar-based items should remain OK to eat if you get them refrozen as soon as possible. Generally speaking, foods that you can refreeze normally will be OK if you have left the freezer open overnight.
Tip
Freezer door won’t stay shut? Use a cabinet safety lock like these to make sure it stays closed. I actually use one on my freezer door.
What are the Other Problems With Leaving the Freezer Open?
Unfortunately, if you leave your freezer door open all night long then there are a few issues you ought to be aware of:
Food Spoilage
Food safety is the most apparent problem because the food inside will begin to defrost. If it defrosts and then sits in that state for an extended period of time, there is a good chance that it will begin to harbour bacteria.
This is especially problematic with meat, fish and dairy products but can be an issue for all food types – especially those that you would normally not refreeze.
As soon as you notice that the freezer door has been left open, quickly inspect the contents and determine if it is still chilled and slightly frozen or not. If it is then there is a chance you can salvage it. If the food is still chilled, close the door and keep it closed for 24 hours.
If you have any doubts or if you spot any form of mould or bacteria growing then, unfortunately, all is lost and it’s time to start throwing it out.
Freezer Component Damage
Food going off/bad is a fairly obvious issue. It’s the one you’re likely to think about first. But what you might not have considered is that leaving your freezer open for an extended period of time can actually impact the freezer itself (the defrost system & the compressor).
Defrost System
Some freezers have an automatic defrost system. If you leave the door open, your freezer has to work hard to keep the temperature down. Obviously, as a machine, it doesn’t know that it’s fighting a losing battle. And, as it continues to cool the inside down, the cold air is constantly escaping. This can cause overheating.
This isn’t helped by the fact that the coils can get covered in ice crystals caused by moisture entering your freezer. As the coils get covered in ice, they become less and less efficient meaning the machine has to work harder to cool.
Compressor
The compressor, which is responsible for cooling the freezer, may experience strain when it has to work continuously to counteract the warm air entering the appliance. Over time, this leads to wear and tear on the compressor, causing permanent damage.
If you want more information on how a freezer works then check out this guide.
Higher Energy Bill
When the compressor in your freezer works harder to maintain a lower temperature (as warm air continuously enters the compartment) you’re increasing your energy consumption.
This, in turn, will likely result in a higher electricity bill….which is a solid “no, thank you” in my book.
What Happens If You Leave the Freezer Door Open for 2 Hours?
Fortunately, if you leave the freezer door open for around 2 hours, the contents and the freezer itself should be fine.
If you find that the door has been open for 2 hours or less then you need to close the door as soon as possible and then leave the freezer shut for 24 hours – regardless of whether or not you’re desperate for ice cream!
What Happens If You Leave the Freezer Door Open for 12 Hours?
At 12 hours, you’ll find that a large level of frost forms across the freezer and the food inside. Most of the food towards the front (and edges) of the freezer will have defrosted. If it is meat, fish or dairy-based then it must be thrown out immediately.
Some fruit, vegetables and herbs will remain safe to eat but their texture will change drastically at this point.
What Happens If You Leave the Freezer Door Open for 24 Hours?
Leaving the freezer door open for 24 hours is when things really start to go wrong. The freezer will be working overdrive to try to keep the freezer cool but the warm air will win this fight.
If your freezer manages to survive the compressor issues, motor burnout, and defrost system failure, you’ll still want to throw most of the thawed food out at this point.
Frost has likely built up, so once all the food is removed you’ll need to defrost the freezer entirely and clean up any excess frost to ensure efficient operation when you start it back up.
What Happens If You Leave the Freezer Door Open for 4 Days?
At 4 days, all will be lost. Even the most robust ingredients that can be frozen over and over will not survive being left in an open fridge for 4 days.
The moment the freezer has been left open for beyond 24 hours, it becomes a case of throwing all the food out, unfortunately. Even though a few vegetables and fruits might be safe to eat, they will be completely mushy and unenjoyable to consume.
This is, unfortunately, the case even if you only left the freezer door open a crack. If the contents are defrosting and have been left like that for multiple days then it’s bad news all round!
How Long Does a Freezer Take to Get Cold After Being Left Open?
This depends on how long the door was left open and how much the temperature has risen. It can take anywhere from a few hours to a whole 24-hour period for a freezer to get cold again.
If your freezer has a temperature monitor then you want to wait until this drop to around -18C or 0F.
Related FAQs
If you still find yourself with questions about what to do if you’ve left your freezer open overnight then these might help you out:
There’s a risk the temperature inside your freezer has risen causing foods inside to thaw. Take the following steps:
Step 1: Close the freezer door tightly.
Step 2: Get a thermometer and check the freezer temp. If the temperature inside the freezer remained close to freezing (40°F and 4°C), the risk of spoilage is low.
Step 3: How long was it open? Ask friends and family when the last person used/opened the freezer. If it’s less than 2 hours, you’re probably good, however, check foods in the “frost zone” near the edges. Throw them out if thawed, or partially thawed.
Step 4: Was it longer than 2 hours and your freezer temp is now registering above 40°F or 4°C? Then you’ll likely need to throw out the food (especially meats!).
You can leave your freezer door open for around 2 hours without the contents or the freezer itself being negatively impacted. Longer than this, and you’ll need to discard the contents, unfortunately.
Yes, leaving the freezer door open can cause long-term damage to the freezer components, especially the coils. As warm air enters, ice crystals form on the coils meaning they have to work harder to cool the temperature down.
Yes, leaving the freezer door open will use up electricity. If the door is open, cool air from inside will escape and warm air from outside will enter. Your freezer then has to work harder to get the temperature back down which will use more power.
I left my freezer door open for about six hours when I came out that evening I found everything defrosted and water all over the floor. No ice buildup no rush just water. What do I do?
We would err on the side of caution, unfortunately and dispose of any meat/fish/dairy products that have defrosted as a minimum.
Check your unit conversion. DegF is wrong
Good spot! -64f would certainly freeze food.
Iv just been to my outside freezer and the door must have been left open the slightest. Most of the food is still frozen but some has defrosted. I have thrown the defrosted food. Will the rest that is still frozen be ok
First off, I’m sorry that happened. It’s frustrating every time.
Now, to your question:
If the food in the freezer has maintained a temperature ABOVE 40 degrees Fahrenheit (4 degrees Celsius) for more than two hours, it may no longer be safe to consume.
However, if the food has remained partially frozen and still has ice crystals, it may be safe to refreeze. The presence of ice crystals indicates that the temperature did not rise significantly, and the food likely did not reach temperatures at which harmful bacteria multiply rapidly. That said, it’s VERY important to check each item individually. And if in doubt, discard the food.
Additionally, perishable items such as meat, poultry, fish, and dairy products are more susceptible to spoilage than items like frozen vegetables or fruits. When in doubt, err on the side of caution.