Buyer's guide

Second-hand CPAP & BiPAP: the complete buyer's checklist

Buying pre-loved sleep therapy equipment is smart, if you know what to check. Most sellers don't disclose what matters most. This guide gives you the full checklist a respiratory therapist would run before recommending any unit.

Quick answer: Before buying any second-hand CPAP or BiPAP, check the logged therapy hours (under 5,000 is generally safer), confirm the pressure settings match your prescription, inspect motor noise and port condition, and never buy masks or tubing second-hand. A free Respyre teleconsult can tell you whether a specific unit is worth the asking price.

The one number that tells you everything: logged hours

The therapy hour counter is built into the device and cannot be reset without a service-level tool, making it the single most tamper-resistant indicator of real wear. Ask every seller to show you this number on-screen before you agree to anything.

Hours logged What it means RT recommendation
Under 2,000 hrs Low use, likely well within service life Generally safe to consider
2,000 to 5,000 hrs Moderate use Inspect internals; check maintenance records
5,000 to 8,000 hrs Heavy use Budget for motor service within 12 to 18 months
Over 8,000 hrs End of recommended service life Avoid for primary therapy

How to check: Power on the device, then enter the clinical menu (the button combination varies by model; your RT can walk you through it during a free teleconsult). Look for a field labelled "Hours," "Device Hours," or "Therapy Hours."

Before you pay

The complete pre-purchase checklist

Run every item on this list before handing over any money. A legitimate seller will cooperate with all of them.

Machine condition

  • Confirm logged hours on-screen (see table above)
  • Power on and listen. Motor should be quiet, no rattling or grinding.
  • Check all ports: air inlet, outlet, humidifier connection. No cracks or discoloration.
  • Ask for the original serial number and cross-reference with the device label
  • Request service history: filter replacements, humidifier chamber swaps, any repairs

Pressure & therapy settings

  • Ask for a copy of the original prescription (pressure range, mode: CPAP, APAP, or BiPAP)
  • Ask the seller to display current pressure settings via the clinical menu
  • Confirm settings match your prescription. Mismatched pressure is a therapy failure risk.
  • Check for a recent AHI log if the device stores it. Consistent readings above 5 are a red flag even on a functional machine.

Mask, tubing & accessories

  • Do not buy masks or tubing second-hand. They are hygienic contact items.
  • Inspect included tubing for cracks, cloudiness, or odor
  • Confirm the humidifier chamber is intact and crack-free; mineral deposits indicate hard-water use without maintenance
  • Plan to replace the filter immediately (cost: minimal)

Seller credibility: the four questions to ask before viewing

"Can I see the device's logged hours on screen right now?" A legitimate seller will show you without hesitation.
"Do you have the original purchase receipt or warranty card?" A paper trail means credibility.
"Why are you selling?" "Upgraded machine" or "no longer need CPAP" are credible; "it stopped working intermittently" is a red flag.
"Was it ever serviced or repaired?" Demand specifics. Vague answers ("I think once, somewhere") are a caution sign.

Avoid units with no original accessories, no serial sticker on the device, or with the clinical menu locked or inaccessible.

Know when to walk

Red flags: walk away

Any one of these is enough reason to pass on a unit, no matter how good the price looks.

  • Seller refuses to power on and show hours on-screen
  • Logged hours exceed 8,000
  • Pressure settings don't match any readable prescription
  • Motor noise: grinding, rattling, or intermittent shutoffs
  • Mold or biofilm visible in the humidifier chamber or tubing
  • Strong odor (cigarette smoke, mildew); filter changes won't fix this
  • "Barely used" but logged hours are above 3,000
  • Missing serial number sticker on the device
Critical point

Don't use someone else's pressure settings

Your CPAP or BiPAP pressure is prescribed specifically to you. Running someone else's settings, even if the machine is otherwise fine, can result in under-treatment (your AHI stays high and you're still not sleeping properly) or discomfort from over-pressure.

Before first use on any second-hand machine, have a licensed RT confirm your pressure settings are loaded correctly. This applies even if the seller claims the settings are "standard" or "default."

What your RT does at setup: connects to the clinical menu, verifies the mode (CPAP / APAP / BiPAP), confirms the pressure range matches your prescription, and documents it so you have a written record. This takes about 10 to 15 minutes and is included in every Respyre home setup visit.
Clinical questions about your specific pressure settings are best answered by your prescribing physician and a licensed RT. Respyre's licensed RT will advise you on your setup.
Respyre Value Picks

Pre-owned units, RT-inspected

Respyre occasionally offers pre-owned CPAP and BiPAP units that have passed a full RT inspection using this same checklist before they are listed.

Hours-verified

Powered on and therapy hours confirmed by a licensed RT partner. No guesswork on the machine's real service history.

Motor & port inspected

Motor health, port condition, and pressure-setting integrity checked and documented before listing.

Cleaned & sanitized

Each unit is cleaned and sanitized before it reaches you. We recommend pairing it with an RT home setup visit.

Returns & warranty on Value Picks

Returns are accepted within 7 days of delivery, provided the logged therapy hours at the time of return do not exceed the hours recorded at purchase by more than 10 hours. This protects you if the unit has a defect that was not apparent at inspection, and it protects us from units that have been used and returned.

Warranty covers manufacturing or mechanical defects only. It does not cover damage from negligence, improper use, unauthorized repairs, dropped units, or water ingress from incorrect humidifier handling.

Respyre is registered with the Philippine FDA. All equipment sold through Respyre, including Value Picks, is sourced from brands with FDA-registered products in the Philippines.

Common questions

Frequently asked questions

How do I check the hours on a second-hand CPAP?

Power on the device and enter the clinical menu (the exact button combination varies by model; your RT can walk you through it during a teleconsult). Look for a field labelled "Hours," "Device Hours," or "Therapy Hours." The hour counter is built into the device and cannot be reset without a service-level tool, making it the most tamper-resistant indicator of real wear.

Are 5,000-hour machines safe to buy?

Machines with 5,000 to 8,000 logged hours are in the heavy-use range. They may still function but the motor is approaching end of recommended service life. If you proceed, budget for motor service within 12 to 18 months. Machines above 8,000 hours should be avoided for primary therapy.

Can I use a second-hand CPAP mask?

No. Masks are hygienic contact items that sit on your face for hours each night. They should not be purchased second-hand. Buy new masks and tubing, even if you are buying the machine itself pre-owned. Inspect any included tubing for cracks, cloudiness, or odor and plan to replace it immediately.

Does Respyre offer pre-owned CPAP machines?

Yes. Respyre Value Picks are pre-owned CPAP and BiPAP units that have passed a full RT inspection before listing. Each unit is powered on and hours-verified by a licensed RT partner, inspected for motor health and port condition, and cleaned and sanitized before it reaches you. Value Picks carry a 7-day return window (provided logged hours on return do not exceed purchase-time hours by more than 10), and warranty covers manufacturing or mechanical defects only, not damage from negligence or improper use.

What pressure settings should I use on a second-hand CPAP?

You must use your own prescribed pressure settings, not whatever the previous owner had loaded. Running someone else's settings can cause under-treatment or discomfort. Before first use on any second-hand machine, have a licensed RT confirm your correct settings are loaded. Respyre's licensed RT will advise you on your specific setup.

Free · no pressure

Not sure if a unit is worth it? Ask a licensed RT, free.

If a seller has given you model details and logged hours, bring them to a Respyre free teleconsult. Our licensed RT will tell you straight whether the unit is worth the asking price or whether you'd be better off with new.