Keep in mind: Before you attempt any of the following, make sure to shut off the power supply to your window air conditioner unit!
1. Blocked Heat Exchanger And Dirty Filters
When the heat exchanging coil or the filters become blocked and dirty, this restricts air flow. As a result, the temperature of the coil will start to fall. If this drops past zero, moisture within the air that condenses on the coil will begin to freeze and create small ice flakes that are then blown out of the unit, resulting in leakage.
Check your filter and if it appears to be dirty, clean it with a shower head or hose. Get rid of all dirt and debris and then spray the filter with a bathroom or kitchen disinfectant to eliminate all bacteria and mold.
Look behind the filters and check the aluminum coil. If this is coated with dry lint, try carefully vacuuming the coil with your vacuum cleaner’s brush attachment. If it happens to be very dirty, you will need to use a spray bottle that contains a powerful degreaser.
Spray this on the coil and let it sit for about five minutes and then use a spray bottle to rinse the coil off. This will eliminate dirt and improve air flow. Make sure to never spray water near the AC unit’s electrical panel.
2. Drains That Are Blocked
With window designs, a blocked drain is fairly easy to identify. Water often drips down the wall from the rear of the unit and it can also leak through the front air outlet when the drain is blocked.
Step on a small ladder and peer down inside of the AC unit from the top. Near the bottom of the heat exchanger you will find a small plastic tray that is meant to catch condensation that the AC unit produces while in cooling mode. Make sure that this tray is not overfull.
If you are unable to resolve the blockage on your own, you will have to contact a local HVAC service provider and schedule service.
3. Your AC Unit Is Leaking And Has Lost Refrigerant
If you have clean air filters and a clean exchanger and your air flow is good, the unit should be able to push out lots of cool air. If it is having a hard time cooling the room down for several hours and begins to leak water from the air vent, it could have an insufficient refrigerant supply.
Adjust your heat pump to the absolute lowest setting and let it run for a while like this. You can then check the exchanging coil that is under the filter. If this is coated in ice, your unit is leaking and it will need to be serviced by a professional. If the unit is leaking coolant, this leak will need to be identified and repaired before additional refrigerant is added.