Question 1

What size dehumidifier do I need?

Accepted Answer

Match the pint capacity to the room size and how damp it is. For a small, slightly damp room, a 20-pint unit is fine. For a mid-size damp basement, 30 to 35 pints. For a large or very wet basement, or a whole level, go for a 50-pint model. When in doubt, size up: a bigger unit runs less often, lasts longer and is quieter than a small one working flat out. Filter by capacity to see suitable models.

Question 2

Do I need a dehumidifier with a pump?

Accepted Answer

A built-in pump lets the unit drain continuously upward, into a sink or out a window, so you never empty the tank. It is worth it if you cannot position the unit above a floor drain, or if it fills fast in a very damp space. Without a pump you either empty the tank by hand or rely on gravity drainage to a lower point.

Question 3

Why are the pint ratings lower than they used to be?

Accepted Answer

In 2019 the US testing standard changed to a cooler, more realistic condition, so a unit that was rated 70 pints under the old test is about 50 pints now, even though the hardware is the same. Modern 20, 35 and 50-pint ratings are the current AHAM figures, so compare within the new numbers rather than old marketing.

Question 4

Are small dehumidifiers less reliable?

Accepted Answer

Testing and owner reports suggest smaller 20 and 35-pint compressor units draw noticeably more reliability complaints than 50-pint models, partly because a small unit in a damp space runs constantly. Sizing up to a 50-pint unit that cycles on and off can actually last longer, which is worth weighing against the higher price.

Most damp-fighting per dollar.

Common questions