Buy a Refurbished ResMed S9 AutoSet: The Cheapest Proven Auto CPAP, and Who Should Still Buy It in 2026
Direct answer: A refurbished ResMed S9 AutoSet is still worth buying in 2026 if you want the lowest-cost proven auto-adjusting CPAP and you accept an older, discontinued machine. The S9 AutoSet is sold out at MyRespCo as of November 11, 2026 (last listed at $249.99). The closest in-stock alternative is the refurbished ResMed AirSense 10 AutoSet at $379.99. Competitor listings found November 5, 2026 put refurbished S9 AutoSet units at $349 to $649, with many at $499. A valid prescription is required in the United States.
What the S9 AutoSet is
The ResMed S9 AutoSet is an auto-adjusting CPAP, also called APAP. It is no longer in production, but it earned a strong reputation for quiet operation at 24 dBA, a low-profile design, EPR, Easy-Breathe technology, and Climate Control with the H5i heated humidifier. Many buyers still search for it specifically because it is proven, simple, and cheap.
What a refurbished S9 AutoSet should cost
| Seller type | Price found |
|---|---|
| Refurbished S9 AutoSet, MyRespCo | Sold out (last listed $249.99) |
| Competitor refurbished S9 AutoSet, no humidifier | $449 (November 5, 2026) |
| Competitor refurbished S9 AutoSet, with H5i humidifier | $499 to $649 (November 5, 2026) |
| Competitor clearance S9 AutoSet, high hours | $125 to $175 (November 5, 2026) |
| Refurbished AirSense 10 AutoSet, MyRespCo (in stock) | $379.99 (November 11, 2026) |
MyRespCo's S9 AutoSet was certified-refurbished with a 1-year warranty and was its most affordable AutoSet option, but it is currently sold out. The market confirms the S9 is the budget entry point, not the premium pick.
Be careful with clearance prices. One clearance listing showed an S9 AutoSet at $175 with 16,789 run hours. That is a very high-hours machine. Price alone does not tell you value. Hours, warranty, and included parts do.
S9 AutoSet vs AirSense 10 AutoSet
| S9 AutoSet | AirSense 10 AutoSet | |
|---|---|---|
| Status | Discontinued, no longer in production | Current proven platform, widely supported |
| MyRespCo availability | Sold out | In stock, $379.99 |
| Competitor refurbished price | $349 to $649 | $439 to $479 (certified pre-owned and refurbished listings) |
| Humidifier | H5i heated humidifier | HumidAir heated humidifier |
| Noise | 24 dBA, very quiet | Quiet, similar class |
| myAir registration | Refurbished units cannot be registered | Confirm with MyRespCo before ordering |
| Parts and accessories | Available, but older platform | Easier to find, current platform |
| Best for | Budget buyers, backup machine, exact replacement for an S9 you already use | Most buyers who want the best value with current support |
Who should buy an S9, and who should not
Buy an S9 if:
- You want the lowest proven auto-CPAP cost
- You already use an S9 and want an exact replacement with the same masks, tubing, and humidifier
- You need a backup machine and do not want to pay AirSense prices for a second unit
- You accept an older machine with no myAir registration
Do not buy an S9 if:
- You want the newest platform, current accessories, and the longest parts life. Buy the AirSense 10 instead.
- You need a machine your sleep clinic can track through myAir. Refurbished S9 units cannot be registered.
- The only unit available has very high hours and no warranty. The saving is not worth the risk.
The 6 checks before you buy a refurbished S9
- Prescription: A valid prescription is required in the US, just like a new machine.
- Run hours: Ask for the exact reading. Hours vary widely in S9 listings, from under 1,000 to over 16,000. Lower hours are worth paying more for.
- Humidifier included: Check whether the H5i heated humidifier is included. A machine-only price is not the same as a machine-plus-humidifier price.
- New consumables: New filter, and new tubing and water chamber where applicable.
- Warranty in writing: MyRespCo describes a 1-year functionality warranty on its refurbished machines. Get the coverage in writing from any seller.
- Return policy: Confirm the return window. MyRespCo describes a 30-day money-back guarantee, with the buyer paying return shipping.
What is usually in the box
A typical refurbished S9 AutoSet package includes the machine, H5i humidifier, power supply, standard tubing, and filters. A carry bag is often not included in refurbished listings, and neither is an SD card. A mask is usually sold separately.
Ready to order?
The S9 AutoSet is sold out at MyRespCo. If you want a proven ResMed auto-CPAP at the lowest in-stock price, order the refurbished AirSense 10 AutoSet at $379.99 and upload your prescription at checkout. Questions? Call or text Yashil Bhatt, RRT, at 706-772-0263. Stock and pricing change, so confirm on the product page.
Frequently asked questions
Is the S9 AutoSet available at MyRespCo?
It is sold out as of November 11, 2026. The closest in-stock option is the refurbished AirSense 10 AutoSet at $379.99.
Do I need a prescription for a refurbished S9 AutoSet?
Yes, in the United States. Refurbished machines require the same prescription as new ones.
Is the S9 AutoSet still a good machine in 2026?
Yes, for the right buyer. It is a proven auto-adjusting CPAP, quiet and reliable when properly refurbished. It is discontinued, so buy it for value and familiarity, not for new features.
Can a refurbished S9 connect to myAir?
No. Refurbished S9 units cannot be linked to myAir or AirView.
How many hours is too many for an S9?
There is no single cutoff, but hours matter more on an older machine. A unit with 16,789 hours is heavily used and should be priced accordingly, with a warranty. Ask for the reading before you pay.
Is the S9 better than the AirSense 10?
Not overall. The AirSense 10 is the newer platform with better support. The S9 wins only on lowest cost and on exact replacement for existing S9 users.
General information only, not medical advice. Whether you need CPAP, APAP, or BiPAP, and what pressure settings to use, comes from your prescriber and sleep study, not from a seller or an article.