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3B Luna II Auto CPAP Machine Review

Written by Audra Sarver Staff Writer
Reviewed by Dr. Dustin Cotliar Medical Reviewer
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Look & Feel

The Luna II Auto machine is black and features a gray top-facing control area and a transparent humidifier tank.

Ideal For

  • CPAP users who experience dry mouth
  • People who find it uncomfortable to exhale against pressurized air
  • Anyone who is unsure whether they need CPAP or APAP

Who Should Keep Looking

  • Individuals looking for a travel-sized CPAP machine
  • Shoppers on a tight budget
  • CPAP users who prefer not to use a humidifier
  • Price


  • Dimensions

    10.79″ x 7.24″ x 4.52″

  • Noise Rating

    28 dBA

  • Weight

    4 lbs.

The Luna II Auto CPAP Machine from 3B Medical is an automatic positive airway pressure (APAP) machine that monitors the user’s breathing and adjusts the air pressure as needed during the night. A continuous positive airway pressure (CPAP) setting is also available.

People with obstructive sleep apnea (OSA) use PAP machines to keep their airway open while they sleep. OSA is a common sleep disorder that can cause pauses in breathing, as well as snoring, gasping, and choking due to the upper airway narrowing or closing. PAP machines deliver pressurized air, helping to normalize the user’s breathing while they sleep.

We’ll highlight the Luna II Auto’s performance, features, cost, and reviews so you can decide whether it’s right for you.

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What You Need to Know About the 3B Luna II Auto CPAP Machine

The 3B Luna II Auto has a fixed pressure CPAP setting as well as an APAP setting that monitors the user’s breathing and auto-titrates to provide the appropriate air pressure level. Some people find APAP more comfortable than CPAP because the air pressure settings automatically adjust to changing breathing patterns as they sleep. Your doctor can determine which type of PAP machine is best for you.

The Luna II Auto also features a built-in heated humidifier, expiratory pressure relief, mask leak detection, WiFi and cellular data sharing, and up to 60 minutes of ramp time. 

We’ll highlight the 3B Luna II Auto CPAP Machine’s features, what’s included with the machine, and its size and cost to help you decide whether it’s the right choice for your needs.

What Comes With It

In addition to the machine and integrated humidifier tank, the Luna II Auto comes with an air filter, power adapter and cord, and tubing.

Like most CPAP machines, the Luna II Auto does not come with a face mask.

Features You Might Like

The 3B Luna II Auto CPAP Machine has a range of features intended to make PAP therapy more comfortable, including a heated humidifier and expiratory pressure relief. The machine also allows users to access and share their therapy data.

APAP Machine Size and Cost

The 3B Luna II Auto is an average size for a CPAP machine with an integrated humidifier. However, it is heavier than the average machine, and its lower profile does translate to a slightly larger footprint than other CPAP machines. Removing the humidifier tank does not reduce the machine’s size. 

While users can travel with the Luna II Auto, those who travel frequently may prefer a travel CPAP machine or one without an integrated humidifier. 

APAP machines are typically more expensive than CPAP machines. The Luna II Auto features a mid-range price-point for an APAP machine with CPAP capabilities. The machine also offers many of the features as a similarly priced CPAP machine in addition to the auto-titration capabilities of an APAP machine. 

How This APAP Machine Performs

Deciding on right CPAP machine can be difficult, but breaking down a machine’s performance into different categories can make it easier to determine whether a machine is right for you.

The 3B Luna II Auto is designed to be easy to use. It has a full color LCD screen with adjustable brightness. Its settings are controlled and selected with a large knob, with separate buttons for ramp and mute. Most people should find the Luna II Auto easy to use, though some may require glasses to read the screen.

The Luna II Auto is compatible with all mask types and standard tubing. However, it is not compatible with heated tubing.

Air pressure measurements are described in centimeters of water pressure, or cm H2O. Like many other APAP machines, the Luna II Auto has a pressure range of 4 to 20 cm H2O.

The Luna II Auto has a sound level of 28 decibels. This is slightly louder than the average APAP machine, though it’s still considered quieter than a whisper. However, those who are very sensitive to sound may prefer a quieter model.

Users can choose between five options for the Luna II Auto’s humidity level. The heated humidifier maintains a set temperature that cannot be adjusted.

3B Medical suggests that users clean the water chamber with a cloth and warm, soapy water on a daily basis. The tubing should also be cleaned every day, while the machine itself should be wiped down weekly with a damp cloth. Users should replace the air filter every two weeks.

Frequent travelers may prefer a smaller APAP machine than the Luna II Auto, which has a slightly larger footprint than comparable models. However, the machine and accessories are still small enough to fit into a carry-on bag.

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What Do Customers Have to Say About the 3B Luna II Auto CPAP Machine?

The 3B Luna II Auto CPAP Machine has received mostly positive reviews from customers. Many users report that the machine’s features provide a comfortable and reliable experience, with the easy-to-use ramp settings and expiratory pressure relief receiving the most praise. 

Most complaints about the Luna II Auto center on the data it provides, which is structured like a doctor’s report and lacks the visualizations provided by comparable models. Some users also dislike scanning the QR code to receive their data, though others enjoy the convenience.

Trial, Warranty, and Shipping Policies

AvailabilityLike other CPAP machines, the 3B Luna II Auto is available only by prescription and must be purchased through a sleep clinic or specialized CPAP retailer. Both brick-and-mortar and online CPAP retailers, like Sleep Doctor, stock the Luna II Auto.
ShippingSleep Doctor and many other online CPAP retailers offer free shipping. However, shipping fees and delivery time vary depending on location and retailer.
Sleep Trial3B Medical does not offer a trial period for the Luna II Auto. It’s a good idea to check the return policies of your chosen CPAP retailer before you make a purchase.
WarrantyThe Luna II Auto comes with a two-year limited warranty covering defects in workmanship or materials for the machine itself. A separate three-month warranty covers components like the humidifier tank and tubing.

Medical Disclaimer: This content is for informational purposes and does not constitute medical advice. Please consult a health care provider prior to starting a new treatment or making changes to your treatment plan.

Still have questions?

Sleep apnea products can be confusing. If you need individualized assistance, send us an email at [email protected] with your questions and we'll help find the best fit for you.

Written by

Audra Sarver, Staff Writer

Audra is a licensed, certified physician assistant and freelance health writer. She has specialized in psychiatry since completing her clinical training in 2018. Her passion for writing was born from the desire to make complex medical information more accessible and understandable to patients and their loved ones. Audra likes to write about all things related to behavioral health and physical wellness. Outside of her work, she enjoys landscape painting, learning new languages, traveling, and spending time with her partner.

Reviewed by

Dr. Dustin Cotliar, Medical Reviewer

Dustin Cotliar holds a medical degree from the State University of NY (SUNY) Downstate College of Medicine, and a master’s in public health from Columbia University, where he focused on healthcare policy and management. He is board-certified in Emergency Medicine, with over eight years of practice that includes emergency medicine, urgent care, and telemedicine.