React Health Luna G3 Auto CPAP
How to set up the React Health Luna G3 Auto CPAP
From the box to your first night. Keep the user guide that came with your machine nearby: if anything here differs from it, follow the guide.
Unpack and check the box
Lay everything out and check for the main device, power adapter, power cord, reusable air filter, carrying case and documents, plus the tubing or heated tubing, SD card and cellular module if your supplier included them. If anything is missing or the box is damaged, call your supplier before first use. If the machine has been in a very hot or cold car, let it sit at room temperature for about 2 hours.
Place it on a firm, flat surface
Put it on a nightstand that is lower than your head, so condensation runs back toward the machine instead of into your mask. Keep it away from heaters, vents and curtains and make sure bedding cannot cover the air inlet.
Fit the filter
With the machine unplugged, attach the black reusable filter to the filter cap. If you use the optional white ultra-fine filter, the reusable filter goes closest to the cap and the white one closest to the machine. Snap the cap onto the back of the device.
Connect power
Push the power adapter plug into the DC inlet on the back, connect the power cord to the adapter, and plug it into the wall. The screen lights up on the main interface.
Fill the water chamber
Open the chamber cap (you can fill it in place or lift it out) and pour in distilled water to no higher than the max fill line, about 360 mL. Close the cap and seat the chamber. Do not move or tilt the machine with water in it.
Attach the tubing and mask
Push one end of the tubing onto the air outlet. For heated tubing, connect the tube to the air outlet and push its power plug into the heated tubing port on the back; the tube icon on the screen changes to a number when it is detected. Connect the other end to your assembled mask.
Insert the SD card
If you have one, slide the SD card into the slot until the correct-insertion symbol appears on the screen. Only remove it when the machine is not blowing air.
Set your comfort options
Open the Initial Setup menu with the knob and set Humidifier, Heated Tubing, Ramp, Mask Type and the clock. Leave pressure settings alone; your provider programs those from your prescription.
Start therapy
Put your mask on, lie down in your sleeping position and press Start/Stop (or simply breathe into the mask, since Auto On is always enabled). Adjust the headgear until there is no air blowing at your eyes. If you feel chest pain, severe headache, shortness of breath or bad bloating, stop and contact your physician.
After setup: settings worth knowing
- Humidifier: Sets how much moisture the heated humidifier adds: Off, Auto, or 1 to 5, where higher is wetter. React Health's rule of thumb: a few droplets in the tube in the morning is about right, lots of water means too high, and a dry nose or mouth means too low.
- Preheat: Warms the water before you go to bed so the first breaths are not cold and dry. It switches itself off after 30 minutes.
- Heated Tubing: Warms the hose to cut condensation (rainout): Off, Auto, or 1 to 5. Only shows when a heated tube is plugged in.
- Ramp: Starts you at a lower pressure and climbs to your prescribed pressure over the ramp time, in 5 minute steps or Auto. You can restart ramp as often as you like during the night. The ramp starting pressure itself is set by your provider.
- RESlex: Exhalation relief: lowers pressure a little as you breathe out so it is easier to exhale. Off or 1 to 3, where 3 lowers the most. The manual describes it as a feature your physician enables, so if you cannot change it, ask your clinician.
- Delay (dry-out): After you stop, keeps blowing air at about 2 cm H2O for around 15 minutes to clear moisture from the humidifier. Set it Off if you want the air to stop instantly.
- Mask Type and Mask Fitting Test: Tells the machine whether you use a Full Face, Nasal or Pillows mask (or Other for non React Health masks). The fitting test shows a "great" icon when the seal is good and "need to adjust" when it is not.
- Accessories reminder: Sets replacement reminders for the filter, tubing and mask (30, 60, 180 or 365 days, or Off) and lets you reset each timer after you replace a part.
- Backlight and brightness: Backlight Auto turns the screen off after 30 seconds without a button press, which helps in a dark bedroom; Brightness sets High or Low.
Supplies that can help
Distilled water is what most CPAP humidifier chambers are meant to be filled with, because it leaves little or no mineral scale behind.
The air inlet filter keeps dust and lint out of the machine and your airway; it is a cheap part that needs regular replacement.
Tubing with a built-in heating wire that keeps humidified air warm all the way to the mask, which is the main fix for rainout (water droplets …
The removable water tank of a CPAP humidifier; it wears and needs replacing, especially if it cracks, clouds or leaks.
A fabric sleeve that slips over CPAP tubing to insulate it, reduce condensation and make the hose feel softer against your skin.
A soft strap that supports the jaw to help keep the mouth closed, used mainly with nasal and nasal pillow masks to reduce mouth leaks.
A long, flexible brush sized to reach the full length of CPAP tubing so you can scrub the inside, not just soak it.
Plain, mild dish soap is the cleaning agent most CPAP makers and the FDA point to for masks, tubing and humidifier chambers.
A padded bag that protects the machine, mask, tubing and power supply in transit.
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Sources
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- reacthealth.com
- fda.gov
- hmenews.com
- api.fda.gov
- sleepfiles.com
Last reviewed October 11, 2026. How we research · Report an error