Where is the drainage hole on my air conditioner?

Most air conditioners drain through a small hole or hose at the bottom rear of the indoor unit or via a condensate line that exits outdoors. The exact location depends on the model and type (window, portable, or split/central).

Air conditioners create condensate as they cool. To locate the drainage point, identify your unit type, then follow the guidance below. Always unplug the unit before inspecting or handling any internal components.

AC types and where drainage is usually found

Window and through-the-wall units

For window or through-the-wall models, the condensate drains from the indoor cabinet. Look for a small drain hole or a hose connection near the bottom of the unit, typically toward the rear or underside. Some models use a removable drain plug that reveals a hole for a drain hose.

Before you start, ensure the unit is unplugged. If you see a small panel or grille at the bottom, check behind it for the drain hole or hose port.

• Bottom rear of the indoor cabinet often houses the drain hole or hose attachment


• Occasionally a removable plug indicates a dedicated drain outlet


• In some designs, the drain hose attaches to a small fitting on the underside


• If there is a front-bottom drainage design, water may exit near the lower front edge

Concluding: If water pools inside or leaks indoors, check for a blocked hose or plug, and ensure the unit is tilted slightly toward the outside to aid drainage. Refer to the manual for the exact hole or hose location for your model.

Portable and floor-standing units

Portable air conditioners typically use a condensate drain hose that runs to a drain, bucket, or floor drain. The drainage outlet is usually on the back or side of the unit, sometimes near the bottom. Some models have a built-in reservoir that you must empty manually.

Safety note: keep the drain hose unobstructed and positioned to avoid kinks that impede flow.

• Back or side of the unit where a plastic hose connects


• A small drain port or cap that can be opened to insert a hose


• Bottom edge of the rear panel may conceal the drain outlet


• Many units require a gravity-fed hose to a floor drain or bucket

Concluding: If you’re unsure where the hose attaches, consult the user manual or model-specific online guide. Regularly inspect the hose for clogs or leaks to prevent overflow.

Split-system and central air (indoor air handler)

In split systems and most central air setups, the condensate drains through a dedicated line from the indoor air handler. The drain outlet is typically a PVC pipe or a small metal tube at the bottom of the air handler cabinet, leading to a condensate line outside or to a condensate pump.

Access is often behind an access panel on the air handler or near the bottom edge of the cabinet. If your system uses a pump, the discharge hose will be connected to the pump outlet.

• Bottom of the indoor air handler cabinet, often toward the back or side


• A PVC drain pipe (commonly 3/4 inch or 1/2 inch) or a small metal outlet


• The line may run to an outdoor condensate drain or to a sump/pump


• Some installations route the condensate to a secondary drain in the attic or crawl space

Concluding: If you notice dripping indoors or pooling around the unit, check the condensate line for clogs or leaks, ensure the line is properly sloped, and verify the pump (if present) is functioning correctly.

How to locate your drainage point quickly and safely

Follow practical steps to find the drainage opening without risking damage to the unit or yourself.

1. Unplug the unit to prevent any electrical hazards.


2. Identify your unit type (window, portable, or split/central) to narrow down probable locations.


3. Inspect the bottom edge of the indoor section for a drain hole, plug, or hose port.


4. Check the back or side panels for a drain hose connection or PVC pipe entry.


5. Consult the user manual or manufacturer website if you cannot locate a clear outlet.

Concluding: After locating the drain, ensure the outlet is clear of debris, the hose is properly connected (if applicable), and the area beneath the unit is kept clean and dry to prevent mold growth.

Maintenance tips to keep drainage working smoothly

Regular care can prevent overflow and mold growth, and help your AC run efficiently.

• Keep the drain area free of dust, leaves, and debris


• Inspect hoses and drains for kinks or leaks


• Ensure proper tilt where required (e.g., window units may need a slight incline away from the wall)


• Clean or replace any accessible drain filters that affect condensate flow


• If you use a condensate pump, test it periodically to confirm it runs when the reservoir is full

Concluding: Proper drainage not only prevents water damage but also helps the unit operate more efficiently and hygienically.

Summary

drainage points vary by unit type: window units often rely on a bottom or rear drain hole or hose, portable units use a back or side drain hose, and split/central systems drain through a PVC line from the indoor air handler. If you’re unsure, consult your model’s manual or manufacturer support. Regular checks and careful maintenance will keep the drainage system functioning and help prevent leaks or mold growth.

How do I locate my AC drain line?

Your AC drain line is a PVC pipe that runs from the indoor air handler (in an attic, basement, or closet) to the outside of your home, often near the condenser unit. It may also connect to another drain, like a washing machine drain or a sink, and some systems have a secondary, higher-up drain line for overflows. Look for the pipe exiting your house, usually made of white PVC, that may have a cap or a T-joint for access.
 
This video explains where to find your AC drain line and how to access it: 1mWillman Air Heating and Air ConditioningYouTube · Apr 29, 2025
Where to look

• Near the indoor unit: Find the evaporator coil housing in your attic, basement, or utility closet. The drain line starts here, typically as a white PVC pipe. 
• Near the outdoor condenser: The line will eventually exit the house near your outdoor AC unit. It's often a white PVC pipe coming out of the wall. 
• Other possible locations: In some homes, the drain line might run to an indoor drain, such as a utility sink or a laundry area. 
• Overflow drain: Some systems have a secondary, higher pipe that is only used when the primary line is clogged. This overflow line will often be visible near a window or door, dripping water when it's in use. 

How to identify it

• It is almost always a white PVC pipe. 
• It is connected to the indoor unit or the drain pan under it. 
• It will lead outside to where it drains condensation. If the line is clean, you may see a steady drip of water here on a hot day. 

This video shows how to identify the primary and secondary drain lines on your AC system: 43sDIY DanYouTube · Apr 10, 2022

Where is the drain hole on an air conditioner?

How To Locate Your AC Drain Pan. The AC drain pan is located in the indoor unit, underneath the evaporator coils, usually on the same side as the air intake. There is a fixed drain pan under the coils and an overflow drain pan below that.

How to unblock an air conditioner drain hole?

To unclog an AC drain line, first turn off the power to your unit. Then, use a wet/dry vacuum to suck out the clog from one end, or pour a mixture of water and white vinegar down the line to help break up the blockage. After the clog is clear, flush the line with water to ensure it is flowing freely before turning the AC back on.
 
Step 1: Turn off the AC and locate the drain line 

• Turn off the power to the AC unit at the breaker box. 
• Locate the drain line, which is a PVC pipe that often has a T-shaped access port with a cap on top. The line will run from the indoor air handler to the outside. 

Step 2: Clear the clog 

• Using a wet/dry vacuum:
  • Remove the PVC cap from the access port. 
  • Use a rag or towel to create an airtight seal around the vacuum hose and the drain line opening. 
  • Run the vacuum for a few minutes to suck out the clog. You may see dirty water and debris come out. 
• Using vinegar and water:
  • Pour a cup or so of distilled white vinegar down the access port to break down algae and gunk. 
  • Let it sit for at least 30 minutes. 
  • Flush the line by pouring a bucket of water down the drain. 

Step 3: Flush and test the line

• Use a garden hose or a cup of water to flush the drain line from the access port to ensure water flows freely and all debris is removed. 
• Check the condensate pan under the indoor unit to remove any standing water and wipe it clean. 

Step 4: Reassemble and restart

• Replace the PVC cap on the access port.
• Turn the power back on to your AC unit. 

How do I check if my AC drain line is clogged?

Here are the most common signs that your condensate line may be clogged:

1. AC System Shutting Down.
2. Visible Water Damage.
3. Water Pooling Around the AC Unit.
4. Musty or Moldy Smells.
5. High Indoor Humidity Levels.
6. Reduced Cooling Efficiency.
7. High Energy Bills.
8. Deteriorating Indoor Unit.