How to Stop an Air Conditioner Unit From Vibrating When It Is Roof-Mounted

It may seem like the house is about to come down when a roof-mounted air conditioning unit starts vibrating.

Fortunately, it's not hard to take care of that annoying rattle and hum. Vibration pads, which can be purchased at many hardware stores or online, can buffer the noise. This simple fix restores your air conditioning unit to a convenient appliance that keeps you comfortable instead of a nuisance that keeps you awake at night.

Climb up a ladder and locate the air conditioner on the roof. Measure the length and width of the base of the air conditioner. Record the measurements and purchase four pads so one can sit under each corner of the air conditioning unit.

Turn off all power to the air conditioner from the inside of the house to make sure it is not running while the vibration pads are being installed. Locate all of the bolts and screws holding the air conditioner in place on the roof. They will likely be drilled straight into a concrete pad that is already installed.

Loosen all of the screws with a power drill and remove all the bolts with a socket wrench. Work from one side to the other until the air conditioner has been loosened from the concrete pad and can be lifted up. Tilt back slightly on the air conditioner and have a friend tip it back toward you to lift up the first corner.

Slide the first vibration pad under the corner of the unit and set it back down. Tilt up the second side and set the next pad under it. Repeat the process for each of the remaining sides until there is a vibration pad under each corner. Check to make sure they are centered under the air conditioner and are all perfectly even.

Tighten all of the screws and bolts back into place on the concrete pad. Verify that the air conditioner is stable on the roof and turn the unit back on to make sure it is not vibrating when in use.

Things You Will Need

  • Ladder
  • Tape measure
  • Power drill
  • Socket wrench
  • 4 Vibration pads

Warning

  • Be very careful when working on a ladder on the roof. Ensure that it is on steady ground before you climb up it.

About the Author

Alexander Callos began writing in 2005 for "The Lantern" at The Ohio State University and has written for various websites, including Bleacher Report, Top Ten Real Estate Deals and Columbus Sports. He has published articles for CBS Sports, SI.com and other websites. He graduated in 2007 from The Ohio State University with a bachelor's degree in public affairs journalism.