NewAir AD-400 40 Pint Portable Dehumidifier
Operates in Low Temperatures and Includes Built-In Humidistat


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NewAir AD-400 40 Pint Portable Room Dehumidifier
Availability: Discontinued
List Price: $ 293.95
Price Break: $44.00
Our Price: $249.95

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Protect your home from mold and mildew caused by excess moisture with the NewAir AD-400 40 pint dehumidifier.  This portable unit is designed for heavy-duty dehumidifying and removes up to 40 pints of moisture daily, making it ideal for medium to large sized areas such as living rooms and basements.  An adjustable built-in humidistat allows you to set the unit to dry the air to the level you choose from 40% to 80% while the automatic defrost function prevents freezing or quick cycling in low temperatures. 

Complete Climate Control
The AD-400 offers complete climate control with its adjustable humidistat, 24-hour programmable timer, automatic defrost function and adjustable fan speeds.

Low Temperature Opertion
The NewAir AD-400 40 pint dehumidifier has an automatic defrost function that prevents freezing in low temperatures. 

Intuitive Control Panel
The intuitive control panel lets you easily select options with the touch of a button.

Fully Portable
The AD-400 comes with rolling casters and a top-mounted handle for easy transport from room to room. 

Breathe Cleaner, Fresher Air
An activated carbon filter as well as a built-in ionizer removes harmful airborne particles such as dust, dander and other allergens.

Prevents Mold & Mildew Growth
The NewAir AD-400 dehumidifier protects your home from mold and mildew caused by excess moisture. 


  • Model: AD-400
  • Product Type: Room Dehumidifier
  • Product Dimensions: 12.13" x 9.38" x 21.25"
  • Product Weight: 23.45 lbs.
  • Product Color: Silver & black
  • Application: Bedrooms, living rooms, basements, and other medium-large sized spaces
  • Voltage: 115 volts
  • Watts: 248 watts
  • Amps: 2.15 amps
  • Frequency: 60 Hz
  • Certifications: ETL, CSAus
  • Dehumidification Capacity: 40 pints per day
  • Dehumidification Technology: Compressor
  • Energy Star Rated: No
  • Water Tank Size: 10.6 pints
  • Automatic Shut-Off: No
  • Refrigerant Type: R134A
  • Operating Temperature: 41°-68°F
  • Adjustable Humidistat: Yes
  • Timer: Yes
  • Timer Length: 24hr
  • Drainage Options: Manual, Continuous
  • Hose Connection: Yes
  • Carrying Handle: Yes
  • Full Tank Alert: Yes
  • Air Filter: Yes
  • Built-In Air Purification System: Yes
  • Air Purification System Type: Ionizer
  • Automatic Defrost: Yes
  • Casters: Yes
  • Control Type: Electronic
  • Suitable for Automobile Use: No
  • Suitable for Commercial Use: No
  • Wall Mountable: No


  • 2 water removal options - empty the bucket manually or use the continuous drainage port
  • Intuitive control panel lets you easily select options with the push of a button
  • Ionizer and activated carbon filter keeps your air fresher, cleaner and healthier
  • Protects your home against mildew and mold caused by excess moisture
  • Removes up to 40 pints of moisture daily - perfect for medium-large sized areas

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Real Customer Testimonials

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Name: Heather Lane
Date: 11/08/2011
Location: Rochester, NY
Overall Rating:

Comments: We have been very happy with the dehumidifier we bought. It has been working consisently, is emptying well and is keeping our basement dry!!
Recommend to Friend: Yes
Name: Robilee
Date: 06/11/2011
Location: Shelburne, Vermont
Overall Rating:

Review Title: Well Designed Room Dehumidifier
Comments: I have owned the NewAir AD-400 40 Pint Portable Room Dehumidifier for just one week; I've used it non-stop in four different rooms and am delighted with the unit's design, quiet operation and portability. The instructions for set-up and operation were straight-forward and clear with one exception: I spent time pondering how the electrical cord was supposed to exit the top of the water tank (there's a small slot for it at the top...but from the directions, I thought that was for installing the permanent drain straw...if you chose to use one). Everything else was 1-2-3....with all the functions I wanted, but no more complications (e.g.: humidistat built-in with varying levels of target humidity percentages, unit stops when the tank is full and waits for you to empty it out and start over). The unit worked quickly & efficiently in my 16x16 finished basement shop/storage room and again in a larger (28 15 or so) one. Then I tried it out in a great room with all the windows open on a humid day....and it actually lowered the humidity in the room despite all the open windows. Now it's out in my recently flooded two-car garage (great Spring for testing this unit)-- I had shallow pools of water on the cement floor after "dry vacuuming" it incompletely yesterday and this AM, I emptied the full tank and admired the few remaining damp spots on the gargage floor (it's back at work drying those out now). :-) The only design element that isn't ideal is the collection tank -- it's a tad awkward to fit back onto the unit. Just takes an extra moment to be sure it's back on properly; would be nice if the cord weren't at the top (to work around) and if there were a solid "snap" once the tank's back in place. But this is minor and I'm sure I'll become proficient at putting it back on soon -- since I'm using the unit happily around the clock (still raining here....). I did a lot of research and am glad I chosethe NewAir AD-400 -- very satisfied thus far. 5 Stars!
Recommend to Friend: Yes
Name: Des
Date: 08/27/2010
Location: Mobile, AL
Overall Rating:

Review Title: Perfect dehumidifier except for one thing
Comments: Living in the deep south, the humidity can be overwhelming. The AD-400 is great at sucking the moisture out of the air, I have to empty it at least 3 times a day, which really makes me wish the tank was bigger, but oh well. My only major complaint is the "alarm" that goes off when it's full. It is unreasonable to promote how quiet the unit is (which it is almost silent while running) and then put a high shrill piercing 20 second alarm on it with no way to turn it off. I can't even count the many times my young children and I have been woken up from naps or bedtime from this thing signaling it is full, and it's located in the living room, not the bedrooms. I now have to make sure it is unplugged during the night so the entire household isn't woken up about 6-7 hours later, which is how long it takes to fill. The is a major issue as I need it to be running 24/7 during the summer. If I thought I could take it apart with a screwdriver and tear out the noisemaker without voiding the warranty, I most certainly would try.
Recommend to Friend: Yes
Name: Des
Date: 08/14/2010
Location: Robertsdale AL
Overall Rating:

Review Title: Very good dehumidifier
Comments: Let me just say, I pretty much LOVE this dehumidifier. We live in the deep south and the humidity is horrible. This unit just sucks the humidity out of the air and pulls the mildewed smell out with it. The only thing bad about it is the alarm that goes off when it's full. It is horribly, piercingly loud and goes on forever, seriously. I can't believe there is no way to turn it off. I can't even tell you how many times it has woken my two young children up from a nap or in the middle of the night. I always try to unplug it before their naps or bedtime but of course I sometimes forget. The tank is so small that it will fill up in about 5 hours, which means if I forget to unplug it, it wakes the whole household up at about 4 am. Ridiculous. On such a perfect unit, I can't believe there is no way to turn off the "fire alarm" that goes off every time the unit is full.
Recommend to Friend: Yes
Name: Laurie
Date: 07/26/2010
Location: Danielson, CT
Overall Rating:

Review Title: Awesome product
Comments: I read all the reviews before I bought this machine and I am in love with it. It's small enough so that it's portable so I figured I could leave it downstairs during the day and then bring it upstairs at night. It did such a fantastic job that I left it upstairs. At the top of the stairs it works on the whole house. When I plugged it in the humidity was 73. After only a few hours it was at 55. It's quiet and I love the air cleaning feature. It's easy to use. The directions were quite simple and it was easy to program. It was very affordable and just perfect. This thing is worth its weight in gold. It has been very hot and humid here and this machine has made life bearable. It's amazing how much water this thing has pulled out of the air. I considered buying the smaller model but the difference in price was so small that I got the bigger one. Well worth buying. I've only had it for about a week but it's wonderful. It does tend to blow some hot air but if I empty the water it has collected then it cools off. It doesn't make any more noise than a fan so it doesn't bother my sleeping. Actually sleeping is easier with this machine because the sheets aren't damp and I'm not sweating in the horrible humidity we've had lately. It's small enough so that it can fit just about anywhere, easy to move on its rolling wheels, and light enough to lift. Thank you to everyone else who bought one for writing the reviews.
Recommend to Friend: Yes
Name: Navy
Date: 07/25/2010
Location: Rib Lake, WI
Overall Rating:

Review Title: Needs basic improvement
Comments: Quiet yes, but two design problems, and other issues. The water storage "tray" has no handles or other gripping devices, making removal difficult and causing a water spill each time. You then must clean up the spill. As others have noted, reinstalling the tray is difficult. Secondly, if you empty the tray before the tray is full (i.e., before the unit has shut itself off), the unit resets the humidistat to 60 and you must reset it. The power "on" light began to work intermittently after 15 minutes. I doubt the accuracy of the humidistat; It reads 12 percentage points lower than two humidometers nearby. No instruction on how to route the power cord so the water tray may be inserted. If I keep this unit, it will only be using constant tube drainage.
Recommend to Friend: No
Name: hwbru
Date: 07/24/2010
Location: Philadelphia, PA
Overall Rating:

Review Title: Works the way it should
Comments: Functions well but probably would be better fit for me in a less humid climate.
Recommend to Friend: Yes
Name: Alli
Date: 07/14/2010
Location: Toledo
Overall Rating:

Review Title: 2 Thumbs up!
Comments: The ordering and delivery of the dehumidifier was flawless. The unit does what it's supposed to and makes a world of difference in my basement!
Recommend to Friend: Yes
Name: Laura
Date: 06/26/2010
Location: Sagamore Hills, OH
Overall Rating:

Comments: I use the NewAir AD-400 Dehumidifier in my basement to help with the dampness. This 40 Pint Portable really does the job and is very quiet! It is also very easy to move, unlike the bulkier dehumidifiers.
Recommend to Friend: Yes
Name: Jeffrey
Date: 06/19/2010
Location: Schererville, IN
Overall Rating:

Review Title: Great dehumidifier for small areas, and a little more.
Comments: I have this in a 1200 sq. ft. ranch house. I have a damp basement and it is too small for that. But it works well upstairs when the air conditioning does not run much, and when the air conditioning runs if it don't run very long. It keeps up most of the time set at 50. Has to run all day, and night I turn off unless humid or compressor still running after the day. Very quiet. Goes on (compressor) at 53 and off at 47, when set at 50. Fan stays on continuous, but is quiet, and better than hearing some loud one come on and off all day. Need to empty once in 24 hours, or twice if very humid. Beeps a short time if full. I usually just empty in the morning. Only bad thing about it, is it always starts at 60 after you turn it on, or a power failure. You need to reset by pressing button over and over: 65, 70, 75, 80, 40, 45, 50, when I set at 50. Compressor comes on when you get to 40. This is an amazing little machine. I believe it is only 200 watts, but I bought it a long time ago, so I'm not sure at the moment. Compressor quieter than refrigerators! Power light goes off when compressor is off. I put a register plastic air deflector to blow the air to the side, instead of out the top, using velcro, and it sets in my kitchen, and blows into the Living Room in the middle of the house. You can get them at hardware stores and they slide to different sizes to fit. Circulates in a larger area that way, instead of just one room.
Recommend to Friend: Yes
Name: Elmoe
Date: 04/26/2010
Location: Saint Paul, MN
Overall Rating:

Review Title: Quiet Dehumidifier That Works Well
Comments: Works great, is very light weight and portable, runs very quietly. Has a removable filter which is a plus. On the down side the water tank is on the back side and is not very big, so emptying it is a bit of a hassle. I'm very happy with it overall.
Recommend to Friend: Yes
Name: J. Robin
Date: 02/22/2010
Location: Greenville, Texas
Overall Rating:

Review Title: NewAir AD-400 Dehumidifier
Comments: This baby knows how to suck water!! Humidity was 89 in my bedroom and really beginning to create problems, the AD-400 has lowered that factor to 65. About every 12 hours the bucket is full and needs to be emptied. Next area to tackle is the storage room. Light weight and on wheels so it can be moved to different locations with no problem. Have to hold the bucket real steady when carrying it to sink to empty or it will slop all or the place. Pretty quiet (about like room fan on medium or high).
Recommend to Friend: Yes
Name: dkwhitmer
Date: 02/19/2010
Location: Oxnard, CA
Overall Rating:

Review Title: Newair ad 400
Comments: Worked well enough I bought a second one.
Recommend to Friend: Yes
Name: M. Lane
Date: 02/18/2010
Location: Stockton, CA
Overall Rating:

Review Title: NewAir AD-400
Comments: The NewAir AD-400 is outstanding. Living on a houseboat I would wake up every morning to water on the glass in all the window. When it was cold I would have to run the heat in all rooms and it was still a little cool. After trying the NewAir AD-400, everything was dry with in 2 days (1,100 sqft houseboat), no more cleaning water from windows glass. Most of all it has reduced my heating cost by half. A friend that lives up where I am purchased one before I did and I didn't really believe it. Seeing is believing, I am a believer now. The only person that is not happen now is my cat, she can't drink the water off the window glass now. Thank you for a 5 star product, I back the NewAir AD-400, a 100%.
Recommend to Friend: Yes
Name: Debbie
Date: 02/17/2010
Location: Edmond, OK
Overall Rating:

Comments: We have a mobile home at the lake. There is a lot of moisture in the mobile home. We turn the dehumidifier on while we are there and it is amazing how much moisture it collects. It's great.
Recommend to Friend: Yes
Name: Martha
Date: 02/11/2010
Location: Durant, OK
Overall Rating:

Review Title: Great product
Comments: I am very pleased with the AD-400 dehumidifier. It lives up to its advertisement. It is compact, easily moved, quiet, and very effective in eliminating excess moisture in my home. I no longer have "sweaty windows!" Additionally, Air-n-Water is great to work with; I am pleased with their customer service and attention to detail.
Recommend to Friend: Yes
Name: S. White
Date: 02/02/2010
Location: Warwick, RI
Overall Rating:

Review Title: New Air AD-400
Comments: Compact, efficient and quiet. I needed to dehumidify an insulated game room in an out building which was getting mildew and is heated only to 45 degrees when not used, but also required quiet while card games are going on. This New Air Unit does the job.
Recommend to Friend: Yes
Name: Peter
Date: 01/30/2010
Location: Nantucket Island
Overall Rating:

Comments: This is the first quiet dehumidifier I've had. It has a smaller capacity than my old 70 pint noise beast but so far so good. If it lasts, it's the best I've seen.
Recommend to Friend: Yes
Name: L. Delorme
Date: 01/21/2010
Location: Vero Beach, FL
Overall Rating:

Review Title: Good Dehumidifier
Comments: The dehumifier is quiet, and does a GREAT job. It sucked so much water from the air I am astounded. The bad smell from water damage has all but disappeared. Great product that I highly reccommend!!
Recommend to Friend: Yes
Name: Losinpig
Date: 01/20/2010
Location: Paradise, CA
Overall Rating:

Review Title: Works Great
Comments: Using to control humidity in a crafts room with many wet things. Works great. Room is 10' x 15'. Runs just about 24/7 and keeps humidity around 50% during rainy weather. No experience yet during summer.
Recommend to Friend: Yes
Name: B. Thibault
Date: 12/04/2009
Location: Seattle, WA
Overall Rating:

Comments: The instructions on how to use this machine were lacking. I think I got everything figured out but I cant tell if the number that shows on the top is the actual humidity level in the room or the one its set at. I am also not sure how much humidity I should have in my basement room. I purchased the unit to help keep the moisture level down and help my jewelry from tarnishing. So far running it 24/7 has not helped. The jewelry is still tarnishing and the little machine is still plugging away. Nothing has changed since purchasing it.
Name: E. Eash
Date: 02/22/2008
Location: Howe, IN
Overall Rating:

Comments: We purchased a dehumidifier for our house because our humidity was 65% to 75%. Windows were fogging up, windowsills were soaked. It works very well. It is rated for 500 square and our house is 1280 square feet, and it works very well to keep humidity down to 50 %.
Name: J. Smiley
Date: 08/06/2007
Location: San Francisco, CA
Overall Rating:

Comments: We picked the AD-400 to dehumidify our apartment. It is performing very well-- cleared our apartment dramatically. We were immediately impressed and thankful that we made the purchase of this model. Slim, sleek, non obtrusive, no buttons or handles stick out quiet, very efficient. Casters help a lot in moving it from room to room. Very effective from such a slim machine and apparently more energy efficient than other brands/models.
Name: D. Rainse
Date: 07/01/2006
Location: North Highlands, CA
Overall Rating:

Comments: I have an excessive amount of moisture in my house (the air). It truly is one of the best investments I've made! I expected it to be much bigger than it really was. I was very impressed with its compact and sleek look! It also arrived about two weeks earlier than expected. Absolutely!! Its works like a dream!! It is so quiet and we noticed a difference immediately (the air smells fresher!).