Cleaning Mold From Your Central Air Conditioner Drain

If you have a central air conditioning unit that utilizes a two-part system to cool your home, then you probably enjoy the convenient and efficient cool air that the system provides. However, when the cool air blown into your home smells moldy and musty, then the air may not be as enjoyable as it once was. If you notice this type of smell coming from your vents, then it is time to investigate the drainage system that attaches to the evaporator that sits in your basement. To learn about the drain, mold formation, and cleaning the part of the system, keep reading.

Understanding AC Drainage

Your air conditioning system will have a series of evaporator coils that run through the interior of the unit. These coils allow copper refrigerant lines to come into contact with warm air. The warmth is pulled from the air and cool air is moved into your house. Moisture is pulled out of the air at the same time that heat is removed. If your basement is wet or if the ambient humidity is high, then a great deal of water may be released. The water condenses on the evaporator coils and drips down into a container. This water must be removed from the AC evaporator to prevent mold and mildew from building inside of it. A drain line connected to the pan or drain condensation container will help to remove the water. In most cases, the drain pan will be tipped slightly so that water moves down and through the drain line as soon as it collects in the pan. 

However, if your air conditioning unit does not run a lot or if your basement becomes incredibly warm and humid, then the drain pan and line can start to form mold. This mold can even block the drainage opening and you may see water pooling around the bottom of the air conditioning unit. Once mold forms, mold spores may move into the air and travel up into the air ducts. You will then smell a musty odor when your air conditioner runs.

Cleaning The Mold

If you smell mold and mildew coming from your cooling vents, then you will need to inspect and clean the drain pan and line inside the evaporator unit. The drain will sit on the bottom of the unit, so look for a panel or opening where you can gain access to the bottom of the air conditioner. Some panels pull away, while others will need to be unscrewed. Shine a flashlight along the bottom of the unit until you find a shallow metal pan. Look to see if the pan is full and also look for signs of mold. 

If you see mold and it appears dark green, thick, and gelatinous, then black mold may have formed on the drain pan. This mold can form in the home where a great deal of water accumulates. While some common molds may also have a wet and slimy appearance, it is best to take precautions if you see what may be black mold. Before you start cleaning the drain pan, purchase a mold testing kit to see if the mold is toxic. You should purchase a kit that specifically tests for the presence of stachybotrys. Look for a surface sampling kit that provides instant results. Use the q-tip or tape to collect the mold from the AC drain pan, then wipe the sample against the mold indicator. Wait for the indicator to produce a positive or negative result.

If the mold is black mold, then contact an HVAC technician from a company like Cape Fear Air Conditioning & Heating Co., Inc. so your drain pan and drain line can be removed and replaced safely. If the mold is not toxic, then clean the drain pan yourself. Use a clean rag to remove the water from the condensation pan. Wipe away as much mold as you can as well. Afterwards, pour about one cup of vinegar in the drain pan and let it sit. The vinegar will eat through the mold clogging the drain line. Use your flashlight to check to see when the vinegar drains from the pan. Mix one cup of water and one cup of bleach in a spray bottle. Spray the drain pan with the mix to kill the remaining mold spores and wipe the pan dry with a clean cloth.