In article .com,
writes:
Yes, evaporative coolers do work, but nothing like as well as ac. They
are very cheap to make, very cheap to run, can knock 4-6C off a room,

And increase the humidity in direct proportion. The wet-bulb
temperature doesn't change at all, which is what counts for
human comfort.

but next to nothing in damp weather, need a bit of ventilation to avoid
causing damp, and can be made yourself from a fan + a wet towel. No
point paying for one.

They work better in hot and very dry climates, which we never
get in the UK.

--
Andrew Gabriel