Video · Coil Cleaning and UV Light
Evaporator Coil Cleaning, Then a UV Light: What Was Inside This Air Handler
Evaporator coil cleaning is the fix when the inside of an air handler gets this dirty. This tech found buildup on the wiring and in the drain pan, and lays out the plan: clean the coil and blower, then add a UV light.
Job footageSwiftPro
- Topic
- Coil Cleaning and UV Light
- Length
- 0:59
- Posted
- September 13, 2026
- Shot by
- The SwiftPro crew, Northern Virginia
What you’re seeing in this video
A young tech pops up in a face-cam corner, pulling disgusted faces, over close-ups of the inside of an air handler. The camera lingers on rusted electric heat strip coils and a wiring harness coated in grime.
He calls what's on the wires and in the supply biological growth, and says that's why the day's job is a coil and blower motor clean-out, including the drain pan. Left alone, he says, it just spreads.
The last step is a UV bulb mounted inside the unit, aimed to keep killing germs on the coil after it's clean.
You guys want to see something nasty? Oh yeah, man. That's rough. It's real rough.
And that's exactly why we're doing a coil and a motor clean out. You get stuff like this growing all over your wires. This is stuff that you see right there. Inside right there there in the supply.
This biological growth. And I was cleaning up this part right here, the pan as well. Because if you don't clean that stuff up, you know, kind of like a disease, like a sickness, it just spreads. And this is exactly what happened in there.
It's not good. So, what we're doing for the day, nice, simple, and easy, it's going to get done just right. We got this UV bulb right here. Essentially, this guy over here is going to go ahead and install into the machine itself, the unit.
It's going to kill all the nasty bad germs. Essentially, just burn them off. So, nothing else spreads. That's the plan for the day.
Why it matters in your house
- Your indoor coil gets wet every time the AC runs. Add dust and you get a sticky film that feeds growth, slows airflow and can bring a musty smell to the vents.
- Blower motor cleaning matters as much as the coil. A caked blower wheel moves less air, works the motor harder and spreads whatever it's carrying through the ducts.
- A UV light for the AC coil helps keep it clean after a cleaning. It doesn't replace filters or maintenance, but it slows the buildup on a damp coil.
How do I know if my evaporator coil needs cleaning?
Musty smells when the AC starts, weak airflow, an AC that runs longer than it used to, or a coil that freezes up are common signs. A tech can open the air handler and look at the coil face, the drain pan and the blower. If the coil face is matted with dust, it needs cleaning.
Want it done at your place? See Coil Cleaning and UV Light at SwiftPro or call (703) 997-9757.
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