Can You Install an Air Conditioner on Its Side?

Compressor and Condenser

• Inside the air conditioner is a compressor and condenser, which are essentially small electric motors. These electric motors, containing moving parts, require lubrication. Their cases are filled with oil in such a way so as to ensure the moving parts are protected from unnecessary friction. Turning an air conditioner on its side upsets the level of these lubricants, and can cause damage to the unit.

Condensation

• Window air conditioners, just like their central air conditioning counterparts, improve indoor conditions by dehumidifying as well as cooling the air. The humidity removed from the air, in the form of condensation on the refrigerant coils, drips down in to a condensation pan. The water then drains from the pan and exits the air conditioner case through drain holes in the bottom. If an air conditioner is turned on its side, this condensation will not drain properly and can cause internal damage, as well as potentially leaking back in to the home.

Air Vents

• Air conditioners have fans or grills on the sides of their case. These allow air to circulate through the unit and heat to be dissipated outside the home, while not allowing rain water in to the case. If an air conditioner is turned on its side, rain will easily drain in to the unit, and cause damage. Water may even leak back in to your home, damaging the window sill and wall.

Securing the Unit

• Air conditioners rely on gravity and properly dispersed weight to remain in place in the window or wall they are installed in. They sit flush against the window sill or bottom floor of their wall opening, and lean slightly outward, spreading their weight on the top and bottom of the opening they are installed in. If an air conditioner is installed sideways, the weight distribution is not ideal, and the air conditioner may fall causing damage to property and anyone standing nearby.