Winterizing Your Air Conditioner

Proper end-of-season care prevents damage, extends your AC's lifespan, and ensures it is ready to go when summer returns. The process depends on your AC type.

Window Air Conditioners

The best approach is to remove the unit entirely and store it indoors. Leaving a window AC installed through winter allows cold air to leak into your home and exposes the unit to freezing temperatures, ice, and moisture damage.

  1. Turn off and unplug the unit at least 24 hours before removal
  2. Remove the unit from the window carefully (it may be heavier than you remember due to internal water)
  3. Clean the filter and wipe down the exterior
  4. Store upright in a dry location (garage, basement, closet)
  5. Cover loosely with a breathable cloth (not plastic, which traps moisture)

Portable Air Conditioners

  1. Drain any remaining water from the tank and drain port
  2. Run the fan-only mode for a few hours to dry internal components
  3. Clean the filter and wipe down the unit
  4. Remove the window kit and exhaust hose, store them separately
  5. Store the unit upright in a dry space

Central AC Outdoor Units

Central AC outdoor units are built to withstand weather. You do not need to cover them — in fact, full covers can trap moisture and attract rodents. However, you should:

  • Clear leaves and debris from around the unit (2-foot clearance)
  • Place a piece of plywood on top to deflect falling ice or branches
  • Turn off the circuit breaker to prevent the system from running during cold snaps

Mini-Split Outdoor Units

If your mini-split has a heat pump function (most do), it will run through winter. Do not cover it or turn it off. Keep the area clear of snow and ice, and ensure the condensate drain is not frozen. If you only use it for cooling, follow the central AC guidance above.

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