Stop the water leak from your air conditioner

The three most common reasons for water leaks from heat pumps are dirty filters or heat exchange coils, blocked drains, and a shortage of refrigerant. They are fairly simple to diagnose and repair.

To remember: Please turn off the power supply of your air conditioner before attempting any of the following!

1. Dirty filters or blocked heat exchanger

When the filters or heat exchange coil are dirty or blocked, this causes a restriction in airflow. This in turn can cause the coil temperature to drop. If the coil temperature drops below freezing, the moisture in the air that condenses on the coil can freeze into small ice flakes that are then expelled from the air conditioner and cause water leaks.

Check the filters and if they look dirty, give them a good cleaning with the hose or shower head. Remove all dirt and spray them with a kitchen or bathroom antiseptic spray to kill any bacteria or mold on them.

Check the aluminum coil behind the filters. If it’s covered in dry lint, try gently vacuuming the coil with your vacuum’s brush attachment. If it’s particularly dirty, you’ll need to use a garden spray bottle and a strong kitchen cleaner that removes grease. Spray it on the coil, let it sit for about 5 minutes, then rinse the coil with the spray bottle. This should remove debris and improve airflow. Be careful not to spray water near the electrical panel of the air conditioner.

ALWAYS read the manufacturers manuals on how to properly clean your heat pump or air conditioner!

2. Blocked drains

On a wall mounted ductless air conditioner, a blocked drain can be quite obvious and easy to diagnose. Water usually drips down the wall from the back of the unit and can also seep through the air outlet in the front if the drain is blocked.

Stand on a small ladder and look down from the top of the air conditioner. Towards the bottom of the heat exchanger is a small plastic pan that is designed to catch condensate produced by the air conditioner’s cooling mode. Check that this tray is not full of water or overflowing.

If your outdoor unit is directly behind the wall the indoor unit is mounted on, your drain pipe is likely to follow the pipes through the wall and leak into the garden. If this is the case, find the end of the drain tube outside, wipe the end clean with a cloth, and then blow as hard as you can. This should remove any blockage.

If you can’t remove the blockage yourself, or if it’s buried inside the wall, you’ll need to call a professional HVAC service company and schedule a service call.

3. Your air conditioner is leaking and has lost refrigerant

If your air filters and heat exchanger are clean and you have plenty of airflow, your air conditioner should provide plenty of cool air. If you have trouble cooling the room for a few hours and then start leaking water from the air vent, you may be low on refrigerant.

Set your heat pump to the lowest possible setting and let it run for a while. Then check the heat exchange coil under the filters. If it’s covered in ice, your air conditioner has a leak and requires a professional to fix. If your air conditioner has a refrigerant leak, the leak will need to be found and repaired before additional refrigerant can be added.

If in doubt, or if these tips don’t work, contact your local air conditioning company for service.