How to Winterize Air Conditioner in 8 Steps


With the onset of cooler weather in Canada, it’s time to prepare your home for winter. For many, winter preparation will include sealing cracks around doors and windows, preparing your gardens and stocking up on supplies such as firewood and road salt.

As you put away your outdoor seating and cover fragile plants in burlap, remember that your air conditioner needs to be prepared for the colder months, too.

Here is a tutorial on how to winterize air conditioner in eight simple steps:

1. Choose the right day for winterization

When the weather starts to cool, keep an eye out for a dry afternoon to winterize your AC unit. While it only takes a few minutes to complete, it is a good idea to turn it off completely before cleaning and allowing to dry.

Picking the right day is key for two reasons: first, you want to make sure you’re not likely to need it again this season and second, so you can take advantage of good weather and allow it to dry out on a sunny day.

2. Get rid of the junk in the air conditioner

Getting rid of the junk is an important step on how to winterize an air conditioner. Between summer windstorms and day-to-day exposure, by the fall your air conditioner is likely littered with leaves, dirt, bird droppings and other debris.

Use a garden hose to spray down both the interior and exterior. Don’t be afraid to use a good amount of water pressure to remove exterior dust and dirt.

3. Don’t forget the air conditioner cover

Before you put away the garden hose, be sure to give your unit cover a good wash. Typically stored in a shed, a garage, or even outside, the covers for air conditioning units often collect debris or become home to bugs and cobwebs over the summer months. Give your cover a thorough cleaning with dish soap and water, then allow to dry completely.

4. Turn off the air conditioner

While every air conditioning unit is different, you can generally turn them off one of two ways. From inside, turn the cooling option on your thermostat off. This will look different on each thermostat model. If necessary, check the user guide for your thermostat to make sure it is properly shut down for the winter.

Outside, you can look for the electrical circuit on the unit itself. It will have a lid, often made of plastic or metal—simply lift the lid and flip the switch to off, in order to cut the power supply.

5. Insulate the air conditioner pipes

Any exposed pipes on your air conditioning unit will need to be protected from freezing over the winter months. You can find foam covers at your local hardware store and simply cut them to fit the size and diameter of your pipes.

Once you’ve done this the first year, you can keep these insulating covers for winters to come. Be sure to place your fittings for tee and elbow joints first, followed by straight sections.

6. Schedule regular air conditioner service

In order to help your air conditioning run smoothly, once spring rolls around, schedule an annual maintenance check now. Your AC unit should be inspected by a professional at least once every year. A well-tuned appliance will use less energy and will run more efficiently.

By scheduling your spring service in the fall, you’ll not only have it on the books, but will also likely have a first crack at appointment times. If your maintenance check reveals any problems, you can hire an air conditioner repair service right away.

7. Communicate with your household

Once you have your air conditioner properly cleaned, prepared and covered, make sure you communicate clearly with your family—it should no longer be turned on. In case you have family members who might be inclined to turn on the AC if they feel warm, you need to make sure they understand not to do so until the unit is prepared for next summer’s use.

8. Keep an eye on the air conditioner

When it comes to winterizing your home, some things to can fix and then forget about until the spring. In contrast, it is a good idea to keep an eye on your air conditioner over the winter. Make sure the cover remains in place, in case the wind or animals dislodge it over time. In addition, be sure to remove snow, ice or other debris from the top of the unit, in order to avoid damage to interior components.

Preparing your air conditioner for the winter is a critical part of home maintenance. The more you can avoid damage from snow and ice, the greater chance you have of avoiding rust damage. In addition, taking these few basic steps will both keep your air conditioner clean and discourage critters from nesting within its structure over the colder months.

If you’ve been wondering how to winterize air conditioner, you likely know that the more you care for your AC unit, the longer it will last. We hope these steps have useful as you plan your preparations for colder weather.