Before You Turn On the AC This Summer, Do These 3 Things or Risk Air Conditioner Lung
It’s barely May and my apartment hit 30C last week. So I caved and turned on the AC.
First night, I started coughing. My throat felt raw. I thought I was getting sick.
Then I remembered: I didn’t clean the AC first.
Turns out I’m not the only one making this mistake. Several readers DM’d me about the same thing — weird smells, mild respiratory irritation, that “icky” feeling when the AC kicks on.
The problem is simple: a dirty AC doesn’t just blow cold air. It blows dust, mites, bacteria, and if it’s been sitting unused all winter, possibly even legionella (the bacteria that causes “air conditioner lung”).
Before you turn on the AC this summer, do these three things:
- Clean the Filter
The easiest and most important step.
- Kill power, open the front panel, remove the filter
- Rinse under water — add a tiny bit of neutral cleaner if it’s grimy
- Let it dry completely before reinstalling (wet filter = mold city)
Monthly cleaning is ideal, every two months minimum.
- Clean the Heat Exchanger (condenser coil)
This is where the bacteria actually live. Use a proper AC cleaner spray on the coil, let it sit 15 minutes, then run the AC on cool for 15 minutes. The grime drains out through the water pipe.
Don’t use regular disinfectant spray — it can damage the coil coating.
- Check the Outdoor Unit
Easily forgotten. Make sure nothing’s blocking the outdoor unit’s vents — leaves, dust, debris. Give it a gentle hose down if needed. Blocked outdoor units work harder and use more electricity.
Do these three things and you’ll breathe easy all summer.