The best dehumidifiers with a built-in pump

A built-in pump is a genuinely useful feature that solves one specific problem, and it gets bought for several problems it does not solve.

Every dehumidifier condenses water somewhere and has to move it somewhere else. There are exactly three options, in order of reliability.

1. Gravity to a drain. A hose from the unit’s drain port, falling continuously to a floor drain, a sump or an outside gully. Nothing to fail, no power, no noise. This is the best answer whenever it is available.
2. A pump. A small pump lifts condensate up and out — to a sink, a laundry standpipe, a window, or a drain at a higher level. Necessary when gravity cannot work.
3. The tank. You carry it. Fine on a small unit in a room you occupy; impractical on a 50-pint unit in a basement.

Before buying a pump, try raising the machine. A stand or a shelf that lifts the unit 12 to 18 inches frequently creates enough fall to reach a floor drain by gravity — and it also gets the intake out of floor-level dust.

This is the useful finding, and it is not what most people assume.

The pump does not cost efficiency. A condensate pump runs in short bursts and draws very little; the certified figures show pump and non-pump 50-pint units sitting on the same 2.01 median.

What it costs is choice. The efficiency leaders in this capacity class — 2.24 and 2.20 L/kWh — do not offer a pump. Requiring one narrows you to the 2.01 group, which is $14 a year more than the best gravity-drained unit.

That is the real trade: not a worse machine, a smaller shortlist.

Worth being blunt about, because a pumped dehumidifier usually lives somewhere nobody looks.

• Pumps clog. Dust and biological growth accumulate in the reservoir and the impeller. A clogged pump means the unit reverts to its tank, fills and stops.
• Pumps have a lift limit. Manufacturers state a maximum head height. Beyond it, the pump runs and the water does not arrive.
• The discharge line is thin and easy to kink. Pump tubing is much narrower than a gravity hose, so a trapped section or a tight bend stops it.
• Where it discharges matters. A pump lifting into a sink is fine. A pump pushing out of a window in freezing weather is a line that will freeze.
• It adds noise. The pump cycles, and a pump cycling at 3 a.m. in a quiet house is audible.

None of that argues against a pump when you need one. It argues for using gravity when you can, and for checking the unit periodically when you cannot.

1. Check the stated lift height against the actual rise to your drain, measured. Do not estimate it.
2. Keep the discharge line short and rising steadily. No dips, no loops, no tight bends.
3. Secure the far end. A discharge tube that works its way out of a sink while you are away empties onto the floor.
4. Keep the gravity option available where the unit supports both. Every model here has a plain drain port as well.
5. Clean the reservoir and filter on a schedule. This is what prevents the clog that stops the pump.
6. Check it periodically if it is somewhere you do not go. A connected unit will tell you; an unconnected one will not.