Dirty AC coil. Do air filters for your air conditioner really work?
We open up a homeowner's AC and show what a standard one-inch filter misses: a coil caked with buildup and an installation mistake that blocked airflow.
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About This Video
This homeowner's house was constantly dusty, and people in the home weren't feeling well. When we opened up her air conditioner, the coil was caked with buildup. Every bit of air in the house had been passing through that.
Her system had a standard one-inch filter the whole time. Those filters don't stop this. We pull coils like this out of homes all the time, and the filter was in place in nearly every one of them.
We also found a second problem: a cover had been left on during the installation that blocked airflow through the unit. When air can't move the way the system was designed for, moisture and dirt build up where they shouldn't, and that's how growth gets started inside an AC. What it looks like is only part of the story. A lab test is what confirms mold, and correcting the cause is what keeps it from coming back.
Video Transcript
George: Okay, come on. So this is what's inside your coil.
Homeowner: Oh my God. Oh my God, that is awful.
George: Look at all that, right? Look at that. Now you know why everyone's been sick.
[...]
George: You know how many of these I pull out of houses? The filter just doesn't do anything, really. Those one-inch filters do nothing. Look at that.
Homeowner: Oh my God, that's so gross. And my house is constantly dusty.
George: Yeah, because of this. But let me tell you the other problem. You see this unit, this right here? This is supposed to come out. And then there was another cover that they took off, right here. See that? This was on here, blocking air.
