Musty Smell when turning on the AC

[Downaski]

Hey everyone!

Have anyone ever experienced musty smell when turning on AC? I am wondering what causes this musty smell?

[machinist]

Hello Downaski!

A musty smell when turning on the AC is actually pretty common and usually caused by moisture getting trapped in the system, leading to mold or mildew growth. It could be due to a clogged drain pan or line, dirty air filters, or even mold in the ductwork. Sometimes, standing water inside the unit can also be the culprit. It’s definitely something you’ll want to tackle since that smell can affect the air quality. A good place to start is by changing the filters, cleaning the drain line, and maybe having your ducts inspected. If it sticks around, calling an HVAC pro might be the best next step!