A vertical window slides upward as opposed to a horizontal window, which slides open to the left or right. A window unit air conditioner is designed for installation in a vertical sliding window. Once the window is opened wide enough, the unit is placed onto the windowsill and the open window slides down behind the air conditioner unit's top guard to prevent the unit from falling out. The unit is secured both in and outside of the window with supportive wood pieces and brackets. L brackets at the top of the open window prevent the window from opening from both the inside and outside. Insulation strips prevent cool air from exiting through leaks and openings created by the installation.
Portable air conditioner units come with a window kit, which contains a window slider component. The window slider component simplifies the portable unit's exhaust hose installation into the window. The exhaust hose expels moisture and airborne impurities from the room out of the window. The window slider component is rectangular and extends wider or shrinks narrower when pulled or pushed from the sides respectively. The piece fits horizontally between the space between an open window sash and the sill. Once the piece is inserted at the bottom of the window, the open window is brought down until the only opening available is the exhaust hose hole on the slider component. One end of the exhaust hooks up to the hole in the window slider while the other end hooks up to the back of the portable unit.
Fitting a window unit air conditioner into a horizontal sliding window is trickier than fitting it into a vertical window as the unit must sit flat and can't be turned vertically. While window units don't come with a horizontal sliding window installation kit, some installation methods still apply, such as L bracket attachment and external and internal wood piece installation for support. The opening above the air conditioner can be covered with plywood, which can be secured to the window frame with screws.
The installation of a portable unit window slider into a horizontal sliding window is a lot easier than installing a window unit air conditioner. Simply orient the window slider vertically, slide the window open to the side, insert the window slider into the opening and close the window to secure the window slider.