System One REMstar AUTO 550 Auto-CPAP Machine with A-Flex (DISCONTINUED)

Philips Respironics System One REMstar AUTO 550 Auto-CPAP Machine with A-Flex (DISCONTINUED)

4.88 Average Rating of 8 Reviews Read Reviews

Discontinued Item:

For Reference: Discontinued February 2014


Philips Respironics PR SYSTEM ONE REMSTAR AUTO brings a wide array of proven technologies together with patient focused advancements -- like advanced humidity controls, mask optimization, and event detection/response -- to create a truly intelligent sleep therapy system.

Everything You Expect and More
The System One REMstar AUTO includes all of the great features you expect from a sleep therapy system including a wide pressure range (4-20cm), patient adjustable ramp, AUTOMATIC altitude adjustment, data card, the latest "flex" comfort technologies, and a universal power supply. In addition the REMstar AUTO is an auto-adjusting CPAP system so it will adjust your therapy levels throughout the night to ensure you are receiving optimum pressure for the most comfortable and successful sleep experience. On top of this the REMstar AUTO features resistance control technologies that adjust to different mask styles, and advanced therapy tracking capabilities -- including advanced event detection, response and reporting.

Flex Technologies - A-FLEX, C-FLEX and C-FLEX+
Respironics natural and clinically-proven "flex" technologies enhance traditional pressure therapy to improve comfort and increase compliance. Thanks to the advanced Digital Auto-Trak algorithm that detects the onset of inspiration and exhalation, the REMstar AUTO delivers just the right pressure relief for every breath, making it easier for patients to adapt to therapy.

SYSTEM ONE CPAP HEATED HUMIDIFIERSystem One Humidity Control with Dry Box
Many CPAP/APAP users find that the addition of heated humidity to their sleep therapy system improves comfort and helps with overall compliance. The optional System One Heated Humidifier delivers optimum humidity, drastically reduces rainout, and provides ultimate comfort throughout the night by analyzing and adjusting to ambient temperature, changing environmental conditions, relative humidity, and therapy flow. Revolutionary Dry Box technology isolates the humidfier's water source from the inner workings of the device to protect against water damage.

System One Resistance Control
System One Resistance Control achieves complete system comfort by enabling the device and mask to work optimally together. Through simple settings, the System One Resistance Control instructs your APAP to compensate for variable resistance characteristics related to different masks. The result is synchronous pressure delivery and the assurance you can enjoy the full benefits of Respironics Flex comfort technologies no matter which mask is used.

Advanced Event Detection & Response
The System One REMstar AUTO tracks, and adjusts therapy levels to respond to, many common OSA related events including Hypopneas, Flow Limitation, Respiratory Effort Related Arousal, Snores, and Leaks. In addition the REMstar AUTO can detect many symptoms beyond classic OSA -- such as clear airway apneas and periodic breathing -- that may indicate the need for specialized therapy.

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Product Information

  • Manufacturer Philips Respironics
  • In the Package PR System One REMstar Auto 550 APAP, SD Data Card, Carrying Case, 2 Reusable Foam Filters, 1 Ultra Fine Filter, Printed Users Manual, Power Cord & External AC Power Supply, 2-Year Manufacturer's Warranty (APAP Only). Heated Humidifier and Additional Custom Options Available in Shopping Cart.
  • Part Number(s) DS550S (Auto-CPAP), DS550HS (Auto-CPAP with Heated Humidifier)
  • HCPCS Code E0601
  • GTIN / UPC Code
  • Warranty 2 Years - Review manufacturer's documentation for full warranty details.
  • Prescription Item Prescription required for the purchase of this item.
  • Country United States of America (Typical Origin)

Physical Specifications

  • Size (Approx) APAP = 7 in x 5.5 in x 4 in APAP with Humidifier = 7 in x 10.75 in x 4 in Power Supply = 4.5 in x 2.5 in x 1.75 in
  • Weight (Approx) APAP = 3 lbs APAP with Humidifier = 4.8 lbs Power Supply = .75 lbs

Performance Specifications

  • Therapy Modes CPAP and AUTO-CPAP (APAP)
  • Pressure Range 4-20 CM H2O
  • Ramp 0 to 45 Minutes (5 Minute Increments)
  • Ramp Start 4 to Min Pressure (User adjustable)
  • Sound Levels Average less than 29 dBA
  • Altitude Adjustment Automatic up to 9000 Feet
  • Event Detection & Response Flow Limitation, Respiratory Effort Related Arousal, Snore, Leak, Obstructed Airway Apnea, Hypopnea
  • Auto On/Off Yes
  • Comfort Technology C-Flex, C-Flex+, A-Flex


  • Masks Compatible with all CPAP/BiPAP Masks
  • Tubing Compatible with all Standard CPAP Tubing, Performance Tubing, and Slim Performance Tubing.
  • Humidifiers SystemOne Integrated Humidifier (Optional)

Therapy Data & Compliance

  • Data Storage More Than 1 Year of Data... Hours of Use, Visual Inspection Compliance, Apnea Hypopnea Index, Flow Limitation, Respiratory Effort Related Arousal, Snore, Leak, Clear Airway Apnea, Obstructed Airway Apnea, Hypopnea, Periodic Breathing
  • Data Included Compliance Visual Inspection Compliance, 7 and 30-day averages

Power Specifications

  • AC (Wall) Power 100-240V, 50-60Hz (Auto Sensing)
  • AC Power Supply Yes


Average Rating of
Total 8 Reviews
  • RemStar Auto 550

    Love the machine!
    Written by H. Patterson, 2014-01-15
  • So far so good

    I bought this machine. To replace my old one. I'm still getting used to it but it does the job. I hope it las as long as my other machines .
    Written by Jorge A, 2013-10-22
  • Excellent

    The A-flex in this unit is a huge improvement over the c-flex on my old Remstar. It is much more comfortable and my compliance has improved. Now they need to make a similar advance in mask technology and design.
    Written by John, 2013-07-10
  • Excellent

    The a-flex is a big improvement over the c-flex on my old Remstar. Much more comfortable and has improved my compliance. The next area needing improvement is mask comfort. I use a fisher-pay kel 407 which is the best I've tried so far. The humidifier is a little awkward to clean, but works ok.
    Written by John , 2013-07-05
  • Amazing Difference

    Just replaced my old CPAP (>5 years) with the Auto 550 with A-Flex. What an amazing difference. It is much quiter, and has very little of the back pressure that the old unit did when I exhale. Don't even need the ramping function anymore. The humidifier is a little harder to fill, but not a problem. Very satisfied with the unit. Wish I had changed sooner.
    Written by End User / Engineer, 2013-03-28
  • REMstar AUTO 550 Auto-CPAP system...

    First a huge thanks to the staff of DirectHome MEDICAL, their knowledge of the products and services is first class. REMstar AUTO 550, a CPAP that is everything I was hoping for. Few products are as good as their advertisements... this is one. This is my fourth system, with A-Flex breathing is effortless. Humidifier with heated tubing is the answer to dryer fall weather. A first class machine combined with world class service.
    Written by Jerry, 2012-11-04
  • A safer Wife

    Got the Cpap in mail much sooner than I thought it would come. I'm very pleased with it and price paid for it. My wife sleeps much better and has more energy through out the day. She is happy and so am I.
    Written by Rick B., 2012-10-29
  • Remstar Auto 550 Auto Cpap

    This is my first machine for apnea. It is easy to use and simple to begin using. I am satisfied with the unit and would recommend it. I have not gotten used to using the heat settings as it made me feel warm and uncomfortable. For now it is fine without heating the water, I am preferring the cooler air flow. The service and delivery was fast.
    Written by Glenn, 2012-10-29