How to Level Your AC Unit

By Laure Justice

June 13, 2025

Ever watched a wobbly ceiling fan and felt a sense of impending doom? Your outdoor AC unit feels the same way when it's not sitting level. A tilted air conditioner isn't just aesthetically displeasing — it's practically crying out for help.

This May Also Interest You: What Size Air Conditioner Do I Need?

Let's straighten things out so you can enjoy the benefits of a level AC unit.

What Happens If Your AC Unit Isn't Level?

A properly leveled AC condenser is essential for the longevity and efficient operation of your entire cooling system. Your AC unit's compressor, which is the heart of your cooling system, depends on proper leveling for optimal performance.

What can happen if it's not level? When your condenser unit sits at an angle:

  • The compressor oil can't properly lubricate components, leading to premature failure.

  • Condensate water may not drain correctly, causing moisture damage and rust.

  • The refrigerant flow becomes unbalanced, reducing cooling efficiency.

  • Your energy bills increase as the system works harder.

  • The unit may vibrate excessively, creating noise and wear.

Even a slight incline can reduce your AC unit's lifespan by years, turning a long-term investment into a much shorter-term relationship with your cooling system.

How Do You Check If Your AC Unit Is Level?

Determining whether your AC unit needs adjustment is a simple process that requires minimal tools and expertise.

Checking whether your AC condenser needs leveling is straightforward with these steps:

  • Visual inspection. Stand back and see if the unit appears tilted.

  • Use a bubble level. Place a 2-foot bubble level on top of the AC unit in multiple directions, working from front to back and then from side to side.

  • Check for vibration. When running, an unlevel unit often vibrates more than normal.

  • Look for water pooling. Water collecting around the unit may indicate improper drainage due to uneven positioning.

Many manufacturers advise installers to level AC units to within 1/4 inch, though some manufacturers allow for a slight tilt to promote more efficient condensate drainage.

How Do You Level an Outdoor AC Unit?

Leveling your AC unit is a manageable DIY project that can save you from costly repairs and improve your system's efficiency immediately.

Things You'll Need

  • Bubble level (2-foot recommended)

  • Adjustable wrench or socket set

  • Concrete or composite leveling pads

  • Work gloves

  • Measuring tape

  • Shovel (if ground preparation is needed)

  • Pea gravel (for base preparation)

AC Unit Leveling Process: Step-by-Step

Follow these systematic steps to correctly level your AC condenser and ensure optimal performance.

Step 1: Safety First

Turn off power to your AC unit at the circuit breaker before beginning any work.

Step 2: Clear the Area

Remove debris, vegetation and obstacles around the unit for complete access.

Step 3: Prepare the Base

If your unit sits directly on the ground, create a stable foundation:

  • Dig down about 4 inches where the unit will sit.

  • Fill with pea gravel.

  • Compact it firmly for a solid, level base.

Step 4: Use Proper Support

Position concrete or composite leveling pads under the unit's feet or corners. These distribute weight evenly and prevent sinking.

Step 5: Make Adjustments

Working methodically from the lowest corner:

  • Lift the unit carefully.

  • Insert leveling pads or shims as needed.

  • Check the level after each adjustment.

Step 6: Verify Your Work

Once adjustments are complete, place your bubble level on top again in multiple directions to ensure proper leveling.

More Related Articles:

Special Considerations for Different AC Types

Air conditioning systems have different leveling requirements, so it's important to know the specifics for your unit type.

Window Units

These should actually tilt slightly backward (up to 1/4 inch) to ensure proper condensate drainage.

Mini-split Systems

Wall-mounted units must be perfectly level for both aesthetic reasons and proper operation.

Heat Pumps

These need proper leveling to ensure melted ice from defrost cycles can drain correctly.

DIY AC Unit Leveling Tips

Even after leveling your unit, ongoing maintenance will help ensure it stays properly aligned.

  • Check your unit's level annually as part of regular maintenance.

  • Watch for signs of settling: unusual vibration, water pooling or decreased efficiency.

  • In areas with clay soil, more frequent checks may be necessary.

  • For severe leveling issues, consider hiring a professional.

Correctly leveling your AC unit is a small task that pays big dividends. By following these steps to level your AC condenser properly, you're setting your unit up for efficient operation and reducing the risk of costly repairs.

View Plans in Your Area
Search Icon

Sign up for HomeServe emails!

Get the latest news, tips and promotional messages, including special offers.