How to Winterize Air Conditioner Window Unit? A Comprehensive Guide

Winterizing your window air conditioner is crucial for its longevity and efficiency, as well as for maintaining the energy efficiency of your home during colder months. Properly preparing your unit involves cleaning, disconnecting, storing (ideally), and sealing the window to prevent drafts and potential damage.

Why Winterize Your Window AC Unit?

Protection from the Elements

Leaving your window air conditioner exposed to harsh winter conditions can lead to significant damage. Freezing temperatures can cause internal components, such as coils and condensers, to crack or corrode. Precipitation, especially snow and ice, can seep into the unit, leading to rust and electrical issues.

Energy Efficiency

Even if your air conditioner is turned off, it can still be a source of significant heat loss. Gaps around the unit create air leaks, allowing cold air to enter your home and warm air to escape. This forces your heating system to work harder, increasing your energy bills.

Preventing Mold and Mildew

Moisture trapped inside the unit or between the unit and the window frame can create a breeding ground for mold and mildew. This not only poses a health risk but can also damage the air conditioner and the surrounding area.

Steps to Winterize Your Window AC Unit

1. Disconnect the Unit: Before you do anything else, unplug the air conditioner from the electrical outlet. This ensures your safety and prevents any electrical shorts.

2. Clean the Air Conditioner: Remove the front grill and clean the air filter. Wash the filter with warm, soapy water, rinse thoroughly, and allow it to dry completely before reattaching it. Vacuum the interior of the unit to remove any dust or debris.

3. Dry Thoroughly: Ensure the unit is completely dry inside and out before storing it. Use a soft cloth to wipe down all surfaces. You can also run the fan-only setting (if available) for a few hours to help dry the internal components.

4. Remove (Ideally): If possible, remove the air conditioner from the window. This is the best option for protecting the unit and preventing drafts. Store it in a dry, cool place, such as a garage, shed, or basement. Cover it with a tarp or plastic bag to protect it from dust and pests.

5. Seal the Window (If Not Removing): If you can’t remove the unit, seal it in place.

   • Insulate Around the Unit: Use foam weather stripping or caulk to seal any gaps between the air conditioner and the window frame.
   • Cover the Exterior: Purchase an air conditioner cover specifically designed for winterizing window units. These covers are typically made of waterproof and insulated materials.
   • Interior Protection: Consider using a heavy-duty plastic sheet or bubble wrap to cover the interior side of the air conditioner. This will add another layer of insulation and prevent drafts.

6. Secure the Window: Ensure the window is properly closed and locked. You can also add additional weather stripping around the window frame for extra protection.

Alternative Solutions for Sealing

While dedicated AC covers are ideal, several alternatives can effectively seal the unit if a cover isn’t readily available:

• Heavy-Duty Plastic Sheeting: Securely tape plastic sheeting over the entire exterior of the unit, ensuring a tight seal.
• Insulated Blankets: Wrap the exterior of the unit with an insulated blanket and secure it with strong tape.
• Cardboard and Tape: In a pinch, cardboard can be cut and taped to fit over the exterior, then sealed with tape for weather resistance.

Frequently Asked Questions (FAQs)

1. Is it really necessary to remove the window AC unit for the winter?

While not absolutely mandatory, removing the unit is highly recommended for optimal protection. Storing it indoors protects it from the elements and reduces the risk of damage, ultimately extending its lifespan.

2. What type of cover should I use for my window AC unit?

Look for covers specifically designed for window air conditioners. These are typically made of durable, water-resistant, and insulated materials. Measure your unit before purchasing a cover to ensure a proper fit.

3. Can I just leave the air conditioner in the window and not do anything?

Leaving the unit unprotected is not advisable. Doing so risks damage to the unit, increased energy bills due to drafts, and potential mold growth.

4. What if I don’t have space to store my air conditioner indoors?

If you must leave the unit in the window, ensure it is thoroughly sealed and covered. Regularly check the unit throughout the winter for any signs of damage or leaks.

5. How do I clean mold or mildew from my air conditioner?

Use a solution of diluted bleach (1 part bleach to 10 parts water) to clean mold or mildew. Always wear gloves and eye protection when working with bleach. Thoroughly rinse the affected area and allow it to dry completely.

6. Can I use duct tape to seal the air conditioner?

While duct tape might seem like a convenient solution, it’s not recommended for long-term sealing. Duct tape tends to lose its adhesive properties over time, especially in cold weather. Use weather stripping, caulk, or specialized sealing tape instead.

7. How often should I check the sealed unit during the winter?

It’s a good idea to check the sealed unit at least once a month to ensure the seals are still intact and there are no signs of leaks or damage.

8. What if my window air conditioner has a drain plug?

If your unit has a drain plug, make sure to remove it and allow any remaining water to drain completely before winterizing. This prevents water from freezing inside the unit and causing damage.

9. Is it okay to use spray foam insulation to seal around the unit?

While spray foam can provide excellent insulation, it can be difficult to remove and may damage the window frame. Consider using it carefully and sparingly, and only if you’re comfortable with the potential permanency.

10. What if I live in a mild climate with relatively mild winters?

Even in mild climates, winterizing your window air conditioner is still a good idea. Protecting it from moisture and preventing drafts will help extend its lifespan and improve energy efficiency.

11. Will covering the AC unit prevent insects from getting inside my home?

Properly sealing the unit will significantly reduce the likelihood of insects entering your home through the air conditioner.

12. What should I do with the window screen that was used with the AC unit during summer?

Clean the window screen and store it in a dry place alongside your air conditioner unit for safekeeping. Re-installation will be a breeze when you are ready to use the AC next summer.

By following these steps, you can effectively winterize your window air conditioner, protecting it from the elements, improving energy efficiency, and ensuring its longevity. A little effort now can save you money and headaches later.