How to Anchor an Air Conditioner Condenser to Concrete

Elizabeth Arnold

An air condenser is a key component of an air conditioning unit that sits outside of a building. Air condensers should be secured to the surfaces they rest upon as they tend to vibrate during use. If the condenser isn't secured in place, the copper piping connected to the HVAC unit inside can kink. You can secure an air condenser to a concrete pad with a hammer drill and specialized concrete anchors that feature sleeves located at their lower ends. Once inserted inside a hole, the sleeves expand to secure the air condenser in place.

Wear a dust mask to prevent concrete dust inhalation.
  1. Place the condenser onto the concrete. Mark the concrete, using the pre-drilled slots located at each corner of the condenser as reference points.

  2. Insert a 1/2-inch-by-4 inch drill bit into a hammer drill. Measure from the tip of the masonry bit 4 inches up and wrap tape around the bit's shaft, if it is longer, to prevent over-drilling.

  3. Slip the tip of the masonry bit inside of the condenser base's pre-drilled slot so that it rests on the concrete surface. Hold the hammer drill at a 90-degree angle from the concrete and squeeze the trigger to begin drilling.

  4. Keep firm pressure on the top of the hammer drill, using the handles for leverage while the masonry bit penetrates the concrete material. Slide the rotating masonry bit up and down inside the hole to remove dust and debris while drilling 3 to 4 inches into the concrete. Stop drilling once the tape wrapped around the masonry bit's shaft reaches the surface of the concrete.

  5. Rotate the concrete anchor's nut until it is flush with the top of the bolt. Slip the tip of the concrete anchor through the condenser base's pre-drilled base and into the drilled hole. Hit the back of the anchor with a hammer until the washer and nut are flush against the condenser base.

  6. Use an adjustable wrench to tighten the nut and expand the anchor sleeve inside the drilled hole. Stop tightening the nut once you cannot rotate it with the wrench. Continue on to the condenser base's next pre-drilled hole and repeat the entire process until the condenser is secured onto the concrete.

  7. Tip

    Use concrete anchors that are designed specifically for outdoor use to prevent rusting.


    When drilling concrete, wear a dust mask and safety glasses to protect yourself from masonry dust.