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Installing a Window Air Conditioner

Installing a window air conditioner needs to be done correctly and carefully for many reasons. You do not want lots of hot air seeping into the room that you want to cool, and you also want the unit to be extremely stable so that it does not fall out of the window and onto the ground or a human being who happens to be walking by your apartment.

Here is quick guide on how to install a window air conditioner:

  1. Get a friend
    Air conditioner units are notoriously awkward to move and to place. Do NOT try to install a unit by yourself. Accidents can cause you to lose your unit out of the window or worse if that unit happens to land on someone walking by your home on the sidewalk below.
  2. Assemble the extensions and brackets, if needed
    Some units have window extensions that need to be assembled to anchor the unit; others have these installed already on the unit. Some models have brackets for attachment to windows, which should be put into place first.
  3. Place the unit securely in the window
    Raise the window pane and put the unit on the windowsill. Slide out the extensions to fill the empty window space on each side. Make sure that the unit is level according to the instructions (most units tip slightly to the outside to aid with drainage). Some units are not to be tilted at all.
    Then, attach the unit to the brackets or lower the window pane to secure the unit in place.
  4. Seal the air conditioner
    Use weather stripping provided by the manufacturer to complete the insulation on the inside. If you are able to reach the outside, use calk to ensure a tight seal. If necessary (odd window shapes, etc.), use plywood boards to fill in any extra space.
  5. Plug the unit in, clean its filter occasionally and remove when unneeded
    Plug in the unit to ensure operation from the chosen outlet or power strip, and to make sure that no circuits will be blown as it is used. Clean the air conditioner’s filter at least twice per year to keep it running efficiently. If you want to remove the air conditioner during cooler months (unnecessary if you have sealed it well!), take it out carefully in a way that preserves the hardware and weather stripping. Store the unit upright, away from moisture or chemicals.

If all worked out as planned, it’s now time to enjoy cool air coming out of your air conditioner.

For a more detailed explanation, just check the video below.