How to defrost a freezer – so it runs efficiently

Discover how to defrost a freezer so it keeps food safe and energy use lower

How to defrost a freezer navy, white and blue fridge freezer in a large open plan kitchen living space - samsung
(Image credit: Samsung)

It’s important to know how to defrost a freezer. A buildup of ice inside the appliance is annoying, reducing the space available for food. But that’s not the only reason that defrosting is an essential task.

When ice builds up the freezer uses more energy to keep the food inside at the correct temperature. In the long run, this could mean a replacement freezer is needed sooner. The other downside? More energy use means higher bills.

In other words, unless you invested in a frost-free model, defrosting the freezer should be one of the tasks on your kitchen cleaning list. Follow these steps to defrost a freezer and keep food safe and costs down.

How to defrost a freezer

The reason you should know how to defrost a freezer? ‘Excessive ice acts as an insulator in a freezer meaning your appliance needs to work harder to keep your food cold,’ explains Vijay Bhadwaj, director at Beko. ‘As a result, the lifespan of your appliance may be reduced and your energy bills will increase. 

‘We recommend defrosting your appliance twice a year or when a frost layer of around one quarter of an inch (7mm) has formed. This will allow the appliance to function correctly and free up any space that the ice may be taking up.’

Whether you're organizing a chest freezer or simply want to clean out a refrigerator/freezer combination, it’ll make life easier if you follow a similar strategy as you do to clean a refrigerator and run food stocks down so there’s less to keep cold while you defrost. 

1. Turn off the freezer and take food out

To defrost a freezer you’ll need to switch it off and unplug from the outlet. Take all the food out and place it in coolers so it doesn’t spoil during the defrosting process.

2. Prepare the floor area

To keep the floor area around the freezer free of water as the ice inside the appliance melts, put down old towels, or newspaper around it. 

Put rags, towels or paper towels inside the freezer, too, to soak up water as the ice melts, and bear in mind that these will need to be wrung out or swapped for dry versions during the defrosting process.

If your freezer has a drainage hose, place this in a bucket or basin, and remember to get rid of the water as necessary during defrosting. You can set shims under the front of the freezer to angle it towards the hose, but do this cautiously because of the weight of the appliance.

3. Remove drawers and shelves

Remove all shelves or drawers from the freezer where possible. However, you may have to wait a while if they’re stuck because of the ice buildup, so don’t force them at this stage of the process of defrosting a freezer. 

4. Allow the ice to melt

Leave the door open to defrost a freezer. Be aware that the process can take a few hours, and don’t be tempted to pick at the ice as you could damage the interior of the freezer.

For safety reasons also avoid trying to shortcut the procedure with a hairdryer, and never use windshield de-icer for an appliance in which food is stored.

5. Mop up and clean

As the ice in the freezer melts, use paper towels or rags to soak up the water. Once the interior of the freezer is frost-free, take the opportunity to clean inside wiping racks, door and inner walls, and removing any food debris that has accumulated in the corners. Then dry the interior.

6. Switch the freezer back on

Once you have dried the interior, switch the appliance back on. It will take a few hours for it to come to the right temperature so be patient and wait until adding your frozen foods back in. Just as with organizing a refrigerator it can be useful to put leftover and fresh food for freezing into transparent containers so you can keep track of the contents of the freezer.

Why is my freezer icing up?

A freezer can ice up for a number of reasons. Warm air enters the freezer when the door is opened which can cause an accumulation of ice over time. ‘Try to limit the amount of times the door is opened every day,’ advises Lucy Searle, editor in chief of Homes & Gardens. ‘And make sure you’re letting hot food cool to room temperature before you freeze it.’

To avoid ice buildup, you should also check the freezer is set to the recommended temperature of 0° F (-18°C). Check the temperature at least once a week, recommends the FDA. 

Can I defrost a freezer without turning it off?

Turn the freezer off to defrost it so that the ice that has built up inside melts. You may see various methods recommended that say you can leave it switched on and then chip the ice off, but this could damage the interior of the appliance, and – if you use a sharp knife – damage you.

Hayley Gilbert
Hayley Gilbert

Hayley is an interiors journalist, content provider and copywriter with 26 years experience who has contributed to a wide range of consumer magazines, trade titles, newspapers, blogs and online content. Specialising in kitchens and bathrooms, she has twice won the CEDIA Award for Best Technology feature. Hayley writes for H&G about kitchens, bathrooms, cleaning, DIY and organizing.