It’s important that the aluminum cooling fins on an air conditioner compressor are straight and even to allow the unit to cool efficiently. If the fins on your AC are bent:

  • Slightly Bent Fins: Run a stiff, plastic, bristle brush back and forth to straighten fins that are partially bent.
  • Badly Bent Fins: Use a putty knife to straighten badly bent fins, being careful not to break or damage the fins.

Watch the video above to find out more.


Joe Truini: There aren’t many repairs a homeowner can make to a central air conditioning system, but here is one. When the compressor gets damaged on the outside the metal fins get crushed like this. It’s important to straighten them out. And here’s one way, with a stiff bristle plastic brush. This one’s made for cleaning tile and grout.

What you need to do is just run the brush up and down the fins using quite a bit of pressure. You’d be surprised you need quite a bit of pressure to straighten these out, even though they’re only aluminum. And this is important because we want air to go completely through these. There we go. That’s better already, after just a few minutes.

It takes three or four minutes to get them all the way straightened out. Now, it’s never going to be perfect, but you can straighten them out so that at least it’s operating pretty efficiently.

Now, if you find any fins that are completely crushed you can very carefully straighten them out with a putty knife. But, again, be careful because you don’t want to damage the fins.

Further Information

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avatar for Joe Truini

Joe Truini

Radio Show Co-Host

Joe Truini is a contractor, author, and the host of “Simple Solutions” on Today’s Homeowner TV and the weekly Today’s Homeowner radio show. He has worked on both large commercial projects and residential remodeling, and has written for national publications such as This Old House and Popular Mechanics. He has also written eight books, including three best-selling shed-building books. Joe lives in Connecticut with his family and enjoys hiking, traveling, and baseball in his spare time.

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