Before You Buy a Dehumidifier: 7 Things That Matter

I bought the wrong dehumidifier twice. The first was a 30-pint unit in an 800 sq ft basement — it ran nonstop and barely budged the needle past 60%. The second was quieter but had no continuous drain, so I was emptying a bucket every eight hours. Third time, I got it right.

Here’s what I wish I’d known.

1. Buying the Wrong Pint Size for Your Space

The mistake: Most people see “30-pint” on the box and figure that’s fine. It’s not. A 30-pint unit handles mildly damp conditions in a small room — a bathroom or closet. Put it in a 600 sq ft basement that smells like a cave and it’ll run 24/7 without catching up.

The right way: Match pint capacity to room size and how wet it actually is:

No 30-pint recommendation past 1,000 sq ft, period. If you’re near a boundary, size up — a 70-pint in a 900 sq ft basement cycles off regularly and lasts longer. The Frigidaire FFAD7033R (~$260) is the 70-pint workhorse most people should look at for basements.

Note: Since 2020, DOE tests at 65°F instead of 80°F, so a “30-pint” under the new standard roughly equals the old 50-pint. Check the spec year if you’re comparing older reviews.

2. Ignoring the Continuous Drain Option

The mistake: “I’ll just empty the bucket when it fills.” Enjoy your new part-time job. A 70-pint unit in a wet basement can pull 3–4 gallons a day — that bucket fills every 6–8 hours. Miss a cycle and humidity climbs right back.

The right way: Get a unit with a continuous drain port (garden-hose-thread fitting) and run a hose to a floor drain or sump pit. The Frigidaire FFAD7033R and GE APER70LZ both have this. Cheap Peltier mini units under $50 don’t.

No drain access? Look for a built-in pump. The GE APER70LZ (~$280) pumps water up to 16 feet vertically — worth every penny if your basement has no floor drain. Renting and can’t modify anything? At least get a 2+ gallon bucket so you’re emptying once a day, not three times.

3. Skipping Auto-Shutoff and a Built-In Hygrostat

The mistake: Buying the cheapest unit with a simple on/off dial and no humidity readout. Leave it on for the weekend and come back to 25% humidity — dry enough to crack furniture, warp doors, and spike your heating bill.

The right way: Get a digital hygrostat that lets you set a target (say 45%) and auto-shuts off when it hits it. Even the Midea MAD50C1ZWS at ~$190 has this. Set it and forget it — the compressor cycles instead of running nonstop, saving energy and adding years to the unit’s life.

Also confirm auto-shutoff when the bucket fills. Every decent model does this, but those $40 mini dehumidifiers on Amazon sometimes just overflow.

4. Dismissing Noise Level Until It’s Too Late

The mistake: You don’t think about decibels until the thing is humming six feet from your bedroom at 2 AM.

The right way: Full-size compressor dehumidifiers are not quiet. Most 50–70 pint units run 50–55 dB on high — roughly a window AC on low. Fine for a basement. Miserable for a living room.

If noise matters: the Midea MAD50C1ZWS runs ~46 dB on low, noticeably better than the 54+ dB typical of others. Two-speed fans let you run quiet during the day and crank it at night when you’re not around. Peltier mini units are truly silent (~30 dB) but only pull 8–10 oz/day — useless for basements.

Add 3–5 dB to whatever the manufacturer claims for real-world expectation.

5. Not Checking the Energy Star Rating

The mistake: You save $20 on the purchase price but ignore that one unit costs $10 more per month to run. Over three years, that “cheaper” model costs $360 more in electricity.

The right way: A non-Energy Star 70-pint unit draws ~700W. An Energy Star one draws ~480W for the same capacity. Real cost at 12 hours/day:

• Non-Energy Star (700W): 8.4 kWh/day → ~$38/month
• Energy Star (480W): 5.76 kWh/day → ~$26/month

$12/month difference, $432 over three years. The Frigidaire FFAD7033R, GE APER70LZ, and Midea MAD50C1ZWS are all Energy Star. If a model isn’t, there’s almost no scenario where the upfront savings are worth it.

6. Overlooking Filter Type and Washability

The mistake: You run the dehumidifier for a year, never touch the filter, and wonder why it pulls less water and runs louder. The filter is caked in dust, airflow is choked, and the compressor works overtime.

The right way: Most modern units use washable mesh filters — pull it out, rinse, dry, slide back in. Do this every 2–4 weeks. The hOmeLabs HUMIDITY (~$230) also sells a carbon filter attachment for musty basements ($15–20 each), nice if odor is part of your problem.

The critical detail: make sure the filter pulls out from the front or top, not the back against the wall. If you have to drag the whole unit out to access the filter, you won’t do it.

7. Paying Extra for Smart Features You Won’t Use

The mistake: You see “WiFi-enabled” and think it’s worth the $50 premium. Six months later, the app hasn’t been updated since 2023, it drops off your network constantly, and you’re walking downstairs to press the button anyway.

The right way: Smart features are worth it in exactly two cases: (1) you want to check humidity while on vacation, and (2) you want to integrate with a smart home routine (Google Home, Alexa) triggered by a humidity sensor. If neither applies, skip it.

Most dehumidifier apps are rough — Frigidaire’s sits at 2.3 stars on the App Store. The GE Connect app is decent, making the GE APER70LZ the best bet if you actually want working smart features.

What is worth paying for: a built-in humidity display, auto-restart after a power outage, and auto-defrost for cold basements (units freeze up below ~41°F without it). Those are practical. WiFi is a maybe.

Basement vs. Whole-House vs. Portable

• Portable (30–70 pint): Good for one room or floor. Everything above applies here.
• Whole-house: Installed in HVAC ductwork or as an AprilAire unit. $1,500–$2,500 installed. Only makes sense if your entire home is humid and you have forced-air HVAC.
• Basement-specific: Same as portable, but prioritize 70-pint, continuous drain, and auto-defrost. Basements are colder (freeze risk), wetter (need capacity), and usually have a floor drain (use it).

When a Dehumidifier Won’t Help

A dehumidifier pulls moisture from the air. It does not fix the source. If water seeps through your walls, pools after rain, or your bathroom has no exhaust fan — a dehumidifier is a bandage, not a cure. Check gutters, seal foundation cracks, install exhaust fans, and stop drying clothes indoors before you buy one. Fix the source first. Then get the dehumidifier to maintain the dry air you’ve earned.

Also on usefulhow.info:

• How to Size a Dehumidifier for Any Room
• Basement Moisture: Fix the Cause Before the Symptom
• Energy Star Appliances That Actually Save You Money