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Beware of the Cottonwood Seeds!

Maybe the title is a bit dramatic, but this possible threat to your outdoor air conditioning unit is something that you may not be aware of.


Here in Central Indiana, there are days in the springtime when the air seems filled with fluffy, airborne seeds. They look similar to the white seed fibers of the dandelion plant–but the ones seen across Indiana in May and June come from the Cottonwood tree. These fluffy seeds are often seen collected together on the ground or on bushes, giving the appearance of a light snowfall. Another place these seeds tend to collect is on your outdoor air conditioner or heat pump unit, known as the condenser – and that’s when these fluffy cloud-like seeds can become a lot less beautiful.

As the fan on your condenser draws in air, grass clippings, small leaves, and yes, cottonwood seeds are also sucked in. These particles can easily become trapped in the condenser fins that surround the unit, often accumulating to several layers thick.  The built-up layer of seeds and other debris can become so thick that the condenser can become clogged, causing the system to work harder and less efficiently. If the airflow is severely restricted by the build-up, it can even cause a complete shutdown of your air conditioning system.

cottonwood build-up on AC


If you notice a layer of built-up cottonwood seeds on your condenser such as the image on the left, you can call Star Heating and Cooling at 317-753-0279 to get us to come out and do a thorough cleaning. If you have a Preventative Maintenance Agreement with us, this is already one of the services you would receive at one of our twice-annual visits to your home.


Or if you would like to take on the task yourself, you may want to try to follow these step by step instructions  to do it yourself. Be sure to remember to shut down the power to the unit before you attempt any cleaning or maintenance on your own.