How many decibels is a dehumidifier?
A dehumidifier's decibel figure depends on the fan speed and the maker: Frigidaire's 22-pint Wi-Fi model, for one, lists 43 dBA on low and 49 on high. ENERGY STAR certifies dehumidifiers for efficiency and does not rate noise. Every decibel figure here comes from the maker, and none states a measuring distance or a test standard.
The makers fall into four groups.
A figure for each fan speed.
Frigidaire's spec sheets list low, medium and high. The 22-pint Wi-Fi model is 43, 46 and 49 dBA. GE listed low and maximum, 43 and 45 dBA for its 22-pint ADYR22LC and 46 and 49 for the 35-pint ADYR35LC, but GE has discontinued both.
Two figures, one speed named.
Danby's spec sheet lists "Quiet operation" at 48 dB, with no fan speed, and a "Decibel Rating (High)" of 56 dBs, with no weighting for either.
One figure, no speed.
hOmeLabs says 47 dB for its 25-pint unit and 38 dB for its 8-pint unit. Waykar puts 33 dB in the product name.
Nothing.
Midea publishes no noise figure for the Cube on its US product page, and GE lists none for its current ADHE models.
A single figure with no fan speed is hard to use. Frigidaire's own range shows why: its cheaper 22-pint model lists 47.5 dBA on low, and its Wi-Fi model lists 43. Those are both "quiet" 22-pint dehumidifiers from one brand, four and a half decibels apart at the speed you would use at night.
Our decibel chart places this 43 to 49 dBA dehumidifier band beside a fridge hum and ordinary talk.
For every current US Frigidaire dehumidifier we found, speed by speed, see our Frigidaire dehumidifier decibels page.
What does the pint rating on a dehumidifier mean?
A dehumidifier's pint rating is how much water it removes in a day, under test conditions that some makers set far warmer and wetter than a bedroom. This is where the category gets slippery, and it matters for noise, because the quietest claims are attached to the most generous capacity claims.
Since June 2019, the Department of Energy has tested portable dehumidifiers at 65°F, where it used to test at 80°F. ENERGY STAR explains that the cooler temperature reflects a basement, and that a unit tested the new way will report a smaller capacity.
Some makers still quote capacity in far warmer, wetter air.
Waykar sells the PD160B-PRO-B as a 34-pint dehumidifier, with the conditions stated in its specifications: 95°F and 90% humidity. ENERGY STAR lists the same model number at 10.16 pints a day under the standard test.
hOmeLabs leads with "64 pint" for its 25-pint unit.
The 64 is a maximum at 95°F and 90% humidity.
Neither maker is hiding the conditions. But a bedroom is not 95°F at 90% humidity. The ENERGY STAR product finder lists every certified model's capacity under the same test, and it takes a minute to check.
Can a 33 dB mini dehumidifier dry a room?
No, a 33 dB thermoelectric mini dehumidifier cannot dry a damp bedroom, because it removes only about half a pint of water a day. Two units in this guide publish about 33 dB: the Eva-Dry EDV-1100 and the Pro Breeze mini. Both are thermoelectric. They have no compressor, which is why they are quiet and why they draw only about 22 watts.
They also remove very little water. Eva-Dry's manual gives approximately 8 ounces a day, measured at 86°F and 80% humidity. Pro Breeze's manual gives approximately 9 ounces in similar conditions. That is about half a pint. A 22-pint compressor unit removes more than forty times as much, in cooler test conditions.
They have a place: a wardrobe, or a cabinet under a sink. In a bedroom with a damp problem, they will run all day and change nothing.
What size dehumidifier does a bedroom need?
A 22-pint dehumidifier suits most bedrooms, and a 35-pint unit suits a basement bedroom with a real damp problem. That follows ENERGY STAR's sizing table, which is simple. For a small to medium room, under 2,000 square feet:
- Slightly to moderately damp, where the room feels damp and smells musty at times: 20 to 30 pints a day.
- Very damp, where damp spots appear on walls or floors: 25 to 40 pints.
- Wet, where walls or floors sweat: 30 to 50 pints.
For a whole basement, our basement dehumidifier guide ranks larger units with drains and pumps. For a sealed crawl space, or one ducted unit for the whole house, see our crawl space dehumidifier guide.
How do you make a dehumidifier quieter?
To make a dehumidifier quieter, stand it on a flat, sturdy surface, leave clearance, close the room, use the low fan at night and mind the temperature.
Danby's manual says a surface that is not flat and sturdy could result in excessive noise and vibration.
Leave clearance. Danby asks for 16 inches at the air outlet, front and rear, and 8 inches at the sides. ENERGY STAR says units without a top-mounted discharge should stand away from walls and furniture so air can circulate.
Close the room. ENERGY STAR says doors and windows should be closed while the unit runs, so it dries the room efficiently.
Use the low fan speed at night. On Frigidaire's figures, low is 6 dBA quieter than high. The same advice holds for a purifier in the bedroom, as our air purifier guide explains.
Mind the temperature. ENERGY STAR says that below 65°F frost can form on the coils, which makes the compressor cycle on and off. In a cold room, look for a unit rated for low temperatures.
Which dehumidifier is best for light sleepers?
For light sleepers, the best dehumidifier holds the low fan all night with the display off, as Frigidaire's Quiet mode does, and has its bucket emptied at bedtime.
Beside a bed, a dehumidifier is judged on the hours when nobody touches it: whether a mode holds the low fan, whether the display goes dark, and what happens when the bucket fills.
A mode that holds low
Frigidaire's use and care guide for the FHDD2234W1 says that in Quiet mode "The unit will run in low fan speed for the whole time", with the display off, and the guide for the 35-pint FHDD3534Y1 describes the same mode.
Out of the box the FHDD2234W1 runs in Auto, its factory setting, which picks the fan speed itself. The FHDD2233Y1's guide describes no Quiet mode, so its 47.5 dBA low fan is set by hand.
Danby's manual gives a default of "40% and high fan speed" and says the fan speed "can not be selected in continuous or comfort mode", so choose Low in its Set mode.
When the bucket fills
Frigidaire's guide says the unit "will shut down and the BUCKET FULL indicator will illuminate", and describes no alarm for it. Danby's manual says the compressor and fan turn off, P2 shows on the display and the unit beeps 8 times, and Danby's app sends a bucket full alert.
GE's manual for its discontinued ADYR models says "an alarm will sound for about 10 seconds", and hOmeLabs lists a full-tank indicator with auto shut-off.
The FHDD2233Y1's 0.85-gallon bucket holds 6.8 pints, under 8 hours of water at its full 22 pints a day, and the FHDD2234W1's 1.7 gallons is twice that. Emptying it at bedtime settles the question.
Restarts
When the room reaches its set humidity the compressor stops, and it starts again as the air turns damp. Frigidaire's guide adds an automatic 3 minute delayed start "if the unit is turned off and on quickly", and counts a "high pitched chatter" from today's high efficiency compressors among normal sounds.
A pump model costs decibels
Frigidaire's 50-pint pump unit, the FHDP5033Y1, lists 49 dBA on low, 6 above the FHDD2234W1, and ENERGY STAR lists it at 49.95 pints a day, well past the 20 to 30 its sizing table suggests for a slightly to moderately damp room.
How much should you spend on a quiet dehumidifier?
Around $200 to $230 buys a 22-pint dehumidifier from Frigidaire or Danby, the size that suits most bedrooms.
Under $60 buys a thermoelectric mini unit for a closet.
Around $175 buys the small hOmeLabs unit, with its 38 dB claim and 8 pints at warm test conditions.
Around $200 to $230 is where the real choice sits: the 22-pint units from Frigidaire and Danby. The quietest published figures in this guide are in this range, so there is no reason to spend more for noise alone.
Around $270 buys a 35-pint unit, which you need only if the room is very damp.
What are the most common dehumidifier buying mistakes?
The common dehumidifier buying mistakes are buying the lowest decibel figure, trusting the pint figure in the name, comparing a single figure with a per-speed table, ignoring the bucket and putting a standard unit in a cold room.
The lowest figures belong to units that remove half a pint a day, or to makers who give no test conditions.
Check it against the ENERGY STAR product finder, which uses one test for every model.
Danby's 48 dB and Frigidaire's 43 to 49 dBA may describe much the same machine. We cannot tell, because Danby does not name the speed behind its 48 dB.
Ignoring the bucket
A small bucket fills fast, and a full bucket stops the machine. Frigidaire's cheaper 22-pint unit holds 0.85 gallons, and its Wi-Fi model 1.7 gallons. In an apartment with no floor drain, those gallons are carried to the sink by hand, so the bucket weighs as much in the choice of an apartment dehumidifier as the decibels do.
Putting a standard unit in a cold room
Below 65°F, frost on the coils makes the compressor cycle on and off without removing moisture.
Waykar's 33 dB and hOmeLabs's 38 dB come with no fan speed or distance, and without those, comparing decibel ratings from two brands tells you nothing about which machine is quieter.
Check the FHDD2234W1's 43 dBA on low against how quiet is quiet enough for the room it will run in; in a bedroom, that means the low fan, not 49 on high.
If a dehumidifier you own has grown noisier, rule out a surface that is not flat and sturdy, which Danby ties to excess noise and vibration, and frost cycling in a room below 65°F, then turn to why your appliance got louder.
