How to Seal a Window Air Conditioner for the Winter (6 Easy Steps)

Window air conditioners come in handy on hot summer days and nights, but what do you do with them in the winter? Since the hassle of completely removing them in the winter months isn’t worth the trouble, you’ll need to know how to seal a window air conditioner for the winter.

Step 1: Clean the air conditioner, removing the filter and any debris from its months of operation.

Step 2: Reposition the air conditioner, making sure it fits snugly to the window.

Step 3: Measure the window’s frame to get the dimensions of the gap.

Step 4: Use a pen knife and foam sealing strips to cover the gaps between the unit and the window frame.

Step 5: Cover the outside of the unit in aluminum foil.

Step 6: Cover the exterior of the unit with a weatherproof cover.

Read on to learn more about how to insulate your AC unit for the cold winter months.

how to seal a window air conditioner for the winter

What happens if you don’t cover your AC in the winter?

If you do not cover your AC unit in the winter, the compressor can freeze, and the entire unit can be damaged like the fins, fan blades, and other components to rust or seize up. The evaporator coil can also freeze, which will block airflow and cause the AC to stop working.

Step-by-Step Guide on how to seal a window air conditioner for the winter

While you can remove the air conditioner from the windows in winter, it is often not as straightforward as most people would want it to be. That’s why the steps below should come in handy, helping you seal the air conditioner, including the necessary tools and materials required to complete the job.

What Will You Need?

You will need your air conditioner to be off while doing this. That will help you avoid any accidents and give you an easier time sealing the air conditioner.

Step 1: Clean the air conditioning unit

Clean the air conditioner and remove any debris that might be inside it. At the end of summer, your AC unit will likely have a lot of dust buildup and debris in the filter. Though this isn’t essential for winterproofing your window air conditioning unit, this does make an opportune time for cleaning it.

Step 2: Reposition the air conditioning unit to fit the window snugly

Reposition the air conditioner to fit snugly on the window. It would be best if you positioned it right in the middle or center of the window.

Step 3: Measure the window frame

Use the tape measure to find out the entire width of the window’s frame. Measure also the length of the covering material that secures the air conditioner on the window’s edges. Record the measurements somewhere if you can commit them to memory, well and good. When measuring with the tape measure, ensure you get the correct measurements to effectively seal the window air conditioner.

Step 4: cut and fit the foam sealing strips

Use the knife and cut the foam sealing strips to the corresponding lengths and widths you recorded in the previous step. Then, cover the air conditioner with these strips, ensuring you have covered all areas around it.

That should give some tight insulation around the air conditioner.

Step 5: Cover the exterior of the AC unit with aluminum foil

Cover the air conditioner’s face with a reflective cover such as aluminum foil. If you can get a cover that blends with your house’s interior décor, then it would be a win. You don’t want to pick a color that will clash with your house’s colors.

Step 6: Cover with a weatherproof exterior cover

Get a breathable material cover and put it on the air conditioner’s exterior. Not only will it prevent rust from wreaking havoc on the air conditioner’s components, but it will also prevent the wind from entering your house in the cold winter months.

It will be easier to shake off and remove the ice that might accumulate on the air conditioner as the winter proceeds.

And that’s how you seal a window air conditioner. Some air conditioners come with specific covers that you can use to cover them in the winter, so make sure you purchase the appropriate cover to avoid buying something that won’t be a good fit.

Read Also: Air Conditioner Makes Loud Noise When Starting – Fix It Easily

Why Should You Seal Window Air Conditioners?

Sealing your window air conditioning unit in the wintertime will allow you to better climate control your living space. It can also help you decrease the cost of your heating bill in the winter and ensure that you’ll have a dry and cozy cold season.

Some parts of the US follow the four seasons winter, summer, spring, and fall. The air conditioners are, therefore, a must-have in the summer to avoid baking inside the house. However, when winter comes around, most people would agree that they have little use for air conditioners. That’s because, in the winter, you will want all heat to remain in the house to avoid freezing to death.

Air conditioners, if left unsealed, would bring in cold air that would further make the temperatures in the house colder. So that’s why you need to ensure you either remove them or seal them to prevent that.

Although some air conditioner models would be easy to remove, it is usually a hectic process that would then appear useless when winter ends, and you have to replace them on the windows again.

That’s why most people only seal or cover them to prevent the entry of cold air and then unseal them when winter ends.

Read Also: Can You Use a Window Air Conditioner Without a Window – What You Should Know

What if You Want to Remove the window Air Conditioner Altogether?

This is usually the most effective way to protect yourself from the cold since air conditioners are like an open window that keeps on letting in the cold. The only problem comes with the hassle of removing and storing these units.

You might have bought an air conditioner that is complicated to remove or, worse, irremovable. Some air conditioners, once fixed on the window, will be a permanent fixture. So, yes, it is possible to remove some air conditioners altogether, but that will depend on whether the model you have is removable. Also, if you want to remove it, you will need help since you can’t do it alone. You might need the help of a professional.

The above complications are why most people seal air leaks and the conditioner’s edges during the winter months.

You May Also Like: Portable Air Conditioner Exhaust Hose Gets Hot – Top 5 Reasons

Maintaining Your Sealed Air Conditioner

Follow the steps below to maintain the weather-tight seal on your window air conditioning unit during the winter months:

Check the air filter regularly

The air filter in your sealed air conditioner should be checked and changed every 3-4 months to ensure it’s efficient.

Keep the outside of your AC unit clear:

Make sure that all plants, trees, and other debris are kept away from the outdoor unit of your sealed air conditioner. In some climates, snow drifts could climb all the way to 2nd story windows. Make sure your AC unit is clear of all debris, including snow!

Clean and Check the Drain Line: 

Make sure to check the drain line regularly and keep it free from any obstructions.

Check for any loose connections:

Check if there are any loose connections. If you find any, have them repaired as soon as possible.

Inspect the ductwork:

Check the insulation on the ductwork, inspect if there are any cracks, gaps, and air leaks, and make sure all connecting components are secure.

Re-sealing When Necessary:

If there is any leakage in the system, it is essential to re-seal the air conditioner to prevent further damage and loss of efficiency. This can be done by a professional technician.

Summary of How to seal a window air conditioner for the winter

If you didn’t know how to seal a window air conditioner for the winter, we hope we have been of help to you. Our easy-to-follow steps will help you seal your window air conditioner and prevent the entry of frost and wind in the winter.

You don’t have to remove the air conditioner from the window now that you know the best way to deal with leakages.

In winter, it is also important to invest in a space heater to keep your home warm and save on energy costs. It can be a great way to do this without having to worry about tripping breakers. For that, you can check – Best 5 Space Heaters That Won’t Trip Breaker – Reviews In 2022.

How often should I check my air conditioner in the winter?

You should check your air conditioner at least once a month during the winter months to make sure that it is covered and properly secured. You must inspect the unit for signs of damage from cold weather and make any necessary repairs before using it during warmer months.

Is it safe to leave my air conditioner uncovered in the winter?

No, it is not safe to leave your air conditioner uncovered in the winter. Freezing temperatures can cause damage to your unit and can reduce its efficiency.

Should I cover My AC unit in the summer?

No, you should not cover your AC unit in the summer. Covering it in summer can prevent proper air circulation, which can result in overheating and, ultimately, a complete breakdown. To avoid any issues, never cover your outdoor AC unit in the summer.

How to prepare window air conditioner for winter

Follow these steps to prepare your window air conditioning unit for winter:
Step 1: Clean the air conditioner, removing the filter and any debris from its months of operation.
Step 2: Reposition the air conditioner, making sure it fits snugly to the window.
Step 3: Measure the window’s frame to get the dimensions of the gap.
Step 4: Use a pen knife and foam sealing strips to cover the gaps between the unit and the window frame.
Step 5: Cover the outside of the unit in aluminum foil.
Step 6: Cover the exterior of the unit with a weatherproof cover.

How to seal air conditioner on window

Use foam strips to seal the edges of the window frame. Make sure to seal air conditioner holes, such as the vents and the area around the unit.

Relevant Resources:

  1. Can You Recharge a Window Air Conditioner – 2 Best Methods
  2. Air Conditioner Starts Then Stops After Only a Few Seconds – 8 Effective Solutions
  3. Frigidaire Air Conditioner Buttons Not Working – Fix It Now
  4. Can I Run AC Without Filter – Learn From Experts
  5. Why is My Portable AC Producing So Much Water – Top 5 Reasons
  6. Portable Air Conditioner Exhaust Hose Gets Hot – Top 5 Reasons
  7. Can You Use a Window Air Conditioner Without a Window – What You Should Know

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