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Sandman Duo ST BiLevel CPAP Machine with Built In Heated Humidifier
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This item has been discontinued by the manufacturer.
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Prescription Required for Purchase
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Setup is easy & takes minutes
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Item # M-114824-US
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Sandman Duo ST BiLevel CPAP Machine
The Sandman Duo ST is lightweight, compact and user-friendly. The Duo ST BiLevel features an intelligent pressure stability and respiratory events detection system that reacts to an obstruction event. Also, the Sandman Series includes the humidifier technology called HumidControl. The built in humidifier actually measures the temperature outside the chamber and adjusts the heater plate to minimize condensation. At 2.64 pounds, take the Sandman Duo anywhere and feel confident you will receive effective therapy.
Sandman Duo ST BiLevel CPAP Machine
The Sandman Duo ST is lightweight, compact and user-friendly. The Duo ST BiLevel features an intelligent pressure stability and respiratory events detection system that reacts to an obstruction event. Also, the Sandman Series includes the humidifier technology called HumidControl. The built in humidifier actually measures the temperature outside the chamber and adjusts the heater plate to minimize condensation. At 2.64 pounds, take the Sandman Duo anywhere and feel confident you will receive effective therapy.
Learn More About Your New Machine
What is the difference BiPAP and BiPAP ST?
A BiPAP (also referred to as a BiLevel or VPAP) delivers two set pressures, a higher pressure for inhalation and a lower pressure for exhalation.
BiPAP and BiPAP ST machines are similar, as they are both designed to provide the same airway pressure. The difference between a BiPAP and a BiPAP ST is the Spontaneous Timed feature. The ST responds to the user when the minimum number of breaths per minute has not been met. This machine ensures all breaths occur by triggering the user to take another breath within the minute.
For example, a BiPAP might be set at the following:
A BiPAP ST might be set at the following:
BiPAP and BiPAP ST machines are similar, as they are both designed to provide the same airway pressure. The difference between a BiPAP and a BiPAP ST is the Spontaneous Timed feature. The ST responds to the user when the minimum number of breaths per minute has not been met. This machine ensures all breaths occur by triggering the user to take another breath within the minute.
For example, a BiPAP might be set at the following:
- Inhalation Pressure - 10
- Exhalation Pressure - 5
A BiPAP ST might be set at the following:
- Inhalation Pressure - 10
- Exhalation Pressure - 5
- 12 BPM (Breath Per Minute)
How do I choose the machine that is right for me?
We provide our customers with many tools to make informed decisions about their machine purchases. Options include:
- Calling a CPAP Expert Toll Free. 800.356.5221.
- Comparison Charts. These charts compare available machines, feature by feature. If you don't know the meaning of a feature, click on the question mark for a definition. Click on the image or name of the product for more detailed product information, pictures and resources.
Travel CPAP Comparison Chart
APAP Comparison Chart
BiPAP Comparison Chart
- Browse Our Machine Product Categories. These categories show each machine our company offers, ranked by popularity. Popularity is determined by a mix of sales data and our in house opinion of the quality of the machine based on our experience and customer feedback. The best products float to the top of our categories.
CPAP Machine Category
APAP (Auto Adjusting) Machine Category
BiPAP (Two Pressure) Machine Category
How can I compare different machines?
We work very hard to provide many different ways for our customers to compare products. Here are the machine product guides we have created and maintain:
- CPAP Machine Comparison Guide. This guide stacks up every CPAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular CPAPs, or all CPAP machines we sell.
Compare Most Popular CPAP Machines
Compare All CPAP Machines
- Auto Adjusting Machine (APAP) Comparison Guide. This guide stacks up every APAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular APAPs, or all APAP machines we sell.
Compare Most Popular APAP Machines
Compare All APAP Machines
- BiPAP, VPAP and BiLevel Comparison Guide. This guide stacks up every BiPAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular BiPAPs, or all BiPAP machines we sell.
Compare Most Popular BiPAP Machines
Compare All BiPAP Machines
What comes with my machine?
Machines come with a six foot hose, power cord, at least one filter, and manuals. Most manufacturers include a carrying case which is designed specifically for their equipment. CPAP, APAP, and BiPAP machines do not come with a delivery system or mask. CPAP masks must be purchased separately.
To see the list of what specifically comes with each machine, you can Browse for a machine. Then on the product page, click the "Specs" tab to see a full list of what comes with the machine.
To see the list of what specifically comes with each machine, you can Browse for a machine. Then on the product page, click the "Specs" tab to see a full list of what comes with the machine.
Which CPAP masks work on which machines?
Any mask will work with any machine, with one important exception. The ResMed AirMini is only compatible with certain ResMed CPAP masks. Compatible masks for the AirMini are as follows:
- ResMed AirFit™ N20 Nasal Mask
- ResMed AirFit™ F20 Full Face
- ResMed AirTouch™ F20 Full Face
- ResMed AirFit™ P10 Nasal Pillow
When considering another CPAP, APAP or BiPAP machine from ResMed or any other manufacturer, mask compatibility extends to all brands. The AirMini uses non-standard tubing to connect the machine to the mask, and is the primary reason why other masks won't work with the AirMini. Despite this issue, many of our customers consider the AirMini to be an excellent machine.
Are prescriptions required for mask, machine, humidifier, and EPAP purchases?
Yes. Federal law requires we have a valid prescription on file before we ship your mask, machine, humidifier, or EPAP therapy, including Provent and Bongo RX. You will also need a prescription to purchase the Nightbalance POSA device.
We provide many easy ways to get your prescription:
- We can request your prescription for you! When you checkout, just let us know you would like us to request your prescription, or you can log into your account to have us request your prescription.
- Fax your prescription to our toll-free fax number: 866.353.2727, or our international fax number: 713.541.7377
- Email your prescription to cpap@cpap.com
- Upload your prescription in your account, under the Prescriptions Section
- Ask your doctor to fill out our prescription form. We have both a standard prescription form and an EPAP prescription form.
For more information on prescriptions, please see our Prescription Section of the Learning Center.
What does a BiPAP ST prescription need to say?
A BiPAP ST prescription must contain all of the following information:
- One of the following words or phrases: "BiPAP ST", "Synchrony ST", "VPAP ST"
- Your physician's contact information
- Your physician's signature
- The patient's full name
- A backup rate or BPM setting.
- Your inspiration pressure (Also called IPAP or breathing in pressure)
- Example: IPAP 13 CM/H20
- Example: IPAP 13
- Example: IPAP 4 CM/H20
- Example: IPAP 4
- Your expiration pressure (Also called EPAP or breathing out pressure)
- Example: EPAP 13 CM/H20
- Example: EPAP 13
- Example: EPAP 18 CM/H2O
- Example: EPAP 18
What is exhalation relief?
Exhalation relief is a comfort feature which reduces the air flow at the time of exhalation, making the breathing process more natural.
The following are the different types of exhalation relief names by manufacturer.
Here are some machines with an exhalation relief feature:
Transcend Auto miniCPAP™ Machine with EZEX
PR System One REMStar 60 Series Auto with Bluetooth
AirSense™ 10 AutoSet CPAP Machine with HumidAir™ Heated Humidifier
+ See More
The following are the different types of exhalation relief names by manufacturer.
- Philips Respironics = C-Flex, C-Flex+, A-Flex and Bi-Flex
- Resmed = EPR (Expiratory Pressure Relief)
- 3B Medical = RESlex
- Apex Medical = PVA (Pressure Variation Algorithm) Pressure Relief
- Curative Medical = EUT (Expiratory Unloading Technology)
- DeVilbiss = SmartFlex
- Fisher & Paykel = SensAwake Technology
- Human Design Medical = Z-Breathe
- Somnetics = EZEX
Here are some machines with an exhalation relief feature:
Transcend Auto miniCPAP™ Machine with EZEX
PR System One REMStar 60 Series Auto with Bluetooth
AirSense™ 10 AutoSet CPAP Machine with HumidAir™ Heated Humidifier
+ See More
What maintenance is required on machines?
The only care a CPAP, APAP or BiPAP machine requires is to clean or change the filters at the air intake. This keeps the internal parts from accumulating dust. Fine paper filters should be changed out every 30 days, or when they appear soiled. Foam washable filters should be rinsed with clear running water once a week, allowed to air dry, and reinserted.
Here are some other suggested actions to care for your machine:
Here are some other suggested actions to care for your machine:
- Keep the area around your machine clean by removing any dust from the area to improve the air quality delivered to your machine and to you.
- Keep the air intake of the machine unblocked. Curtains, bedding, and papers can easily block the air intake of your machine, reducing the airflow.
- If a humidifier is used with your therapy, do not pick up the machine with the humidifier attached. With most machines it is easy to spill water from the humidifier chamber into the machine causing damage. Manufacturer warranties are voided by water damage to the machine. To avoid this, remove the chamber from the humidifier and then remove the humidifier from the machine rather than transporting them together.
- If a humidifier is used, empty the water from the chamber every morning. Accidents happen. If a family pet or family member moves the machine and humidifier with water in the chamber it is more likely that water could be spilled into your machine. Water damage to a machine voids the manufacturer warranty.
How do I use a battery to operate my CPAP?
All machines can connect to DC power. Some machines are configured to operate on DC Power and have a DC power outlet. Other machines require AC power and will need an Inverter that turns DC power to AC power.
Having the proper equipment is the biggest key to successfully operating the machine from a battery. For example, if your machine does have a DC outlet and you want to run your machine from a marine battery, be sure to get the correct DC cable for the machine, as well as an adapter cable with alligator clips that fits over the cigarette lighter plug.
CPAP.com sells complete battery kits with everything you need for many machines including the correct cables for those machines and batteries. If you have questions about the specific power needs of your machine, review the 'Power' tab found on the machine's product page, or give us a call at 1-800-356-5221.
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When you shop with us, we want you to be confident that you are receiving the best available price. If this items goes on sale or you spot an online or retail competitor with a lower price within seven days of your purchase, let us know, and we will credit you the difference.
"Super helpful, fast shipping, friendly assistance, great selection, I love this company."
- Verified Customer, 10/25/22
★★★★★
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Puritan Bennett
ResMed
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Warranty
2 Years
2 Years
Sound Level
26 dB
26.6 dBA
Quiet
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Yes
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★★★★★
Verified purchase | May. 18, 2010 | Verified CPAP.com Customer
compact,quiet,easy to use
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★★★★★
Great Machine, LOVE this humidifier!
Verified purchase | Sep. 26, 2009 | Verified CPAP.com Customer
I used another manufacturer’s Auto-titrating BiPAP for years to treat my complex apnea (both obstructive and central apnea). I had failed CPAP testing in the hospital sleep lab because I was unable to exhale against sufficient pressure to minimize my obstructive apneas, so we went to the auto-titrating BiPAP to resolve my apneas, and my min EP and max IP pressures were determined. Synchronization combined with auto-titration seemed to resolve my central apneas by forcing progressively harder puffs of air — the only drawback was in this process the machine would often “run away” and go all the way to the machines max pressure of 25 and stay there. As a result, I would wake with the mask blasting air everywhere and I not able to breathe against it. The only resolution was to turn the machine off and back on. I purchased the Sandman Duo ST machine because of the very small and light size of the machine, the description of the “adaptive algorithm” in the machine, and the synchronization feature. It would be much more convenient for travel, and seemed it would possibly resolve issues I had with my previous machine. First, this is NOT an auto-titrating machine, as I had believed from the description of the “adaptive algorithm. Thus, because my pressures were determined as min/max auto-titration, the settings in the Sandman when I received it were way off. Fixed EP/IP pressures were not determined during my sleep study. I could not breathe with these settings, and short of a new hospital sleep study, trial and error were necessary to find pressures that promote good sleep. Are they the “correct” pressures? Neither my doctor nor I can really tell given the limited data the software provides. That said, with this machine I am sleeping very well. I turn frequently during the night and my respiratory rate changes significantly with position and other factors. Though breathing is fully synchronized by the machine, the sensitivity is such that the second I “exhale against the inflow,” the machine switches to exhalation and resynchronizes. My partner reports that I do not snore and, more important, don’t seem to have uncorrected central apnea episodes. Bottom line is that once the pressures and other settings were determined, this very compact machine really does the job. Another real plus is that I have always had to use the humidifiers on previous machines only in pass-over mode. Even on a heat setting of 1, I experienced drown-out. With this machine, I am able to set humidification level where I need it, currently at 4, and experience no drown-out. The humidity sensor really works. Going from an auto-titrating machine with only min/max titrated pressures to a fixed-pressure BiPAP was quite difficult, and gave a bad first impression of the Sandman. Had I had a prescription with correct pressures for this type of BiPAP in the beginning, I would have immediately known this machine is a champion. With correct settings now in the Sandman, I have given up all thoughts of going back to my auto-titrating machine.
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★★★★★
Excellent Machine
Verified purchase | Jul. 27, 2009 | Verified CPAP.com Customer
Received my Sandman Duo ST BiLevel CPAP Machine a few days ago. It was easy to setup and operate. The machine operates perfectly giving me a restful sleep for the first time in many years. I live overseas and the machine arrived 6-days after ordering. I was able to track the progress of the shipment via UPS and was able to call UPS for a last minute change of delivery as it was arriving on the weekend when my office was closed. It was rerouted to my home so I could use it immediately. Thanks all for the speedy order and delivery.
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