Why a cooling coil does two different jobs at once — and why its total BTU/hr rating never tells you the whole story.
Ask someone what a cooling coil does and they'll say "it cools the air." True, but incomplete. A wet cooling coil is quietly doing two separate jobs at the same time: dropping the air's temperature, and wringing moisture out of it. One shows up on a thermometer. The other doesn't show up on a thermometer at all — it shows up as water running out of a condensate drain. Confusing the two, or assuming a coil's total capacity rating captures both equally, is one of the most common sources of "the temperature is right but it still feels clammy" complaints in the field.