Fit and support come before the lift
- Check your unit’s window size, mounting kit and electrical requirements before lifting it.
- Fit the parts that go on the unit while it’s on the floor. Install a separate support bracket first if your kit calls for one.
- Lift with a helper, secure the unit and sash, then seal the gaps.
- Check that the unit is stable, positioned for drainage and running normally.
You have the unit and a window in mind. We’d check the opening and its support first, because a mounting kit that cannot fit securely rules out the installation before anyone lifts the air conditioner. Measure the window and lay out the parts supplied with your model.
Set the unit level or at the slight outward tilt its instructions require so water can drain. Follow your model’s specified position if it differs. For example, LG’s window-unit instructions (opens in a new tab) call for the rear of covered units to sit 10 to 15 mm lower.
Check the window and mounting style
Measure the opening’s height and width against your model’s limits. Check that the window and frame are in good condition and that the supplied hardware fits. If the opening is larger than the kit supports, ask a window AC installer how to mount the unit before you lift it.
| Window or unit | What to check | If the check fails |
|---|---|---|
| Up-and-down sash with a conventional unit | The opening fits the unit’s stated range, and its rail, curtains and support fit the window. | Stop and use the correct mounting kit or ask an installer. |
| Storm-window frame | The frame leaves room for the unit’s required drainage position. | Stop if the frame prevents that position. Ask an installer about the window. |
| Slide-out-chassis unit | Use the opening limits and mounting parts specified for that model. The numbered sequence below does not cover this design. | Follow your model’s slide-out-chassis installation procedure or ask an installer. |
| U-shaped unit | Check that its included bracket fits and can be installed before the unit is set on it. | Stop if the bracket cannot be secured. |
The numbered steps below are for conventional sash units whose rail and curtains attach before the whole unit is lifted. Slide-out-chassis and U-shaped units use different mounting sequences. For the listed Friedrich slide-out-chassis models, follow the installation procedure (opens in a new tab); for other models, use your unit’s installation instructions or ask an installer.
This up-and-down sash sequence does not cover a side-sliding or casement window. Check the installation instructions for a unit intended for your window before proceeding.
Hire an installer if the window is outside the kit’s range or the support cannot be secured. Give them the unit model and instructions, the window’s measurements and construction, and the outlet details. Check your unit’s warranty and service terms before arranging work.
Get the window and power ready
Open the window fully, remove the screen and clean the sill, glass and frame. Gather a tape measure, pencil, scissors, level and the screwdriver your hardware calls for. Keep the supplied fasteners and seals together so you can match each one to its job.
- The window and frame are in good condition, and the mounting parts fit.
- A second person is ready to help lift the unit.
- The unit will not block a fire escape window or another exit.
- Building management has authorized the installation, if required.
Check that the nearby outlet is grounded and has the voltage your unit requires. Check your model’s outlet and circuit requirements, including the fuse or breaker capacity for its maximum current. Make sure the unit’s own cord reaches the outlet. If you cannot confirm that the outlet and circuit meet those requirements, have a qualified electrician arrange the correct outlet or circuit before installing the unit.
Fit the parts that go on before lifting
Match each part to its job in your model’s instructions. On some GE units, attach the top rail and side curtains before lifting (opens in a new tab). On Midea U-shaped units, the included bracket goes in the window first, and the unit is then set on it.
- Fit the supplied top rail if your kit uses one. Check that it is firmly attached with the specified fasteners. If it moves, refit it before lifting.
- Fit the side panels or curtains if they attach to the unit before lifting. Check that each panel sits in its track or frame. If one catches or comes free, take it out and refit it.
- Apply the supplied gasket or weatherstripping where the unit and side curtains will contact the window. Check that it reaches each contact surface. Refit any strip that leaves a gap.
Seat the unit and check its position
Measure and mark the center of the opening before anyone holds the unit. Keep your helper with you until the unit is seated and secured.
- Install any support bracket that your kit says must go in first. Check that it is secured as the instructions require. If it cannot be secured, stop and ask an installer about the window.
- With your helper, lift the unit into the opening and center it on your mark. Seat its bottom rail or base as your model requires. If it does not sit in the specified place, lift it back out and recheck the fit.
- Lower the sash onto the unit’s top rail or into the position specified by its kit. Check that it meets the unit evenly. If it does not, lift the unit out and check the mounting parts.
- Put a level on the unit and check the position required for drainage. Adjust it before fastening anything. If a storm-window frame prevents the required position, stop and ask an installer about the window.
Secure the unit and close the side gaps
Fasten the unit with the brackets, rails and screws specified for its kit. Check that it stays in position without shifting. If the support or a fastener will not hold, stop and ask an installer to resolve it.
Pull the side curtains across the open space and fasten them as your kit directs. Check that each curtain stays in place against the frame. If a panel will not reach or stay attached, recheck the window range and the panel assembly before adding any foam.
Lock the sash and seal the gaps
Fit the sash lock or window bracket supplied with your kit. Check that the sash cannot open and release the unit. If the lock does not fit, stop and resolve the mounting before using the air conditioner.
Cut the top foam gasket to the window’s width and press it into the gap above the lower sash if your kit includes one. Check along the top and both sides for gaps, then refit the seals or use the extra foam called for by your kit.
Keep plants, antennas and other objects off the top of the unit.
Questions that come up during installation
Can I reuse the opening measurements from my old unit?
Measure again and compare the result with the new model’s stated window range. Opening limits differ between models.
Can I use an extension cord if the outlet is too far away?
Don’t use an extension cord. Arrange a suitable outlet within reach of the unit’s own cord before installing it.
Should I drill a hole to let water out?
Don’t drill into the bottom of a Frigidaire room air conditioner. Use the drainage arrangement specified for your own model.
What if a newly installed unit does not cool?
Check that it is installed correctly and that airflow at the front, back and side vents is clear. Check its warranty and service terms. If a Frigidaire unit installed within the past 30 days still does not cool after those checks, contact the installer with the model number and installation details.
Check the installation before you run it
Check that the support is stable, the sash stays locked, the seals close the gaps and the unit still sits in its required drainage position. Plug it into the suitable grounded outlet and check that it operates normally. If it shifts, the sash opens or the drainage position changes, turn it off and correct the installation before using it again.
Check the unit’s position and the window frame again during the season. The support, sash lock and outward drainage position should still match what you set at installation.
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