Banister Stairwell writes:

There are chemicals specifically formulated for the purpose of cleaning
coils. You can find them at Home Depot or Lowe's.

The only thing "special" about these is a label and premium price.

Just use an ordinary butyl cleaner (409, Fantastik, Zep), which is all
these "special formulas" are.

Kind of like the high-priced "seam cement" for wallpaper, which is just
white (PVA) glue. Or the "special" cleaners sold for pressure washers.