CPAP Troubleshooting: Fix Dry Mouth, Mask Leaks, and Pressure Issues
Nov, 23 2025
Why Your CPAP Isn’t Working (And How to Fix It)
You’re using your CPAP every night. You’ve followed the instructions. But you still wake up with a dry mouth, your mask keeps leaking air, and the pressure feels too high-or too low. You’re not alone. About 42% of CPAP users deal with dry mouth, 58% report mask leaks, and nearly one in three say pressure settings feel off. The good news? Most of these problems have simple, proven fixes. You don’t need to quit therapy. You just need to know where to look.
Dry Mouth? It’s Probably Not the Humidifier
Most people assume dry mouth means their humidifier isn’t working hard enough. But that’s not usually the case. According to sleep specialist Dr. Raj Dasgupta, dry mouth in CPAP users is caused by mouth breathing during sleep-not low humidity. When air escapes through your mouth, it pulls moisture from your throat and tongue, leaving you parched.
Here’s what actually helps:
- Switch to a full-face mask if you’re using a nasal mask. A full-face mask covers both nose and mouth, so air can’t escape even if your mouth opens during sleep. One Reddit user reported dry mouth vanished within three nights after switching.
- Use a chin strap. These simple straps hold your jaw closed. About 45% of mouth breathers find relief with them, according to Sleep Foundation data.
- Turn up your humidifier-but not too high. Most machines have settings from 0 to 6. Start at level 3 or 4. Going higher than 5 can cause condensation in the tubing (rainout), which makes things worse.
- Try heated tubing. It keeps warm air from cooling down before it reaches your mask. Philips’ 2022 clinical trial showed heated tubing reduces dry mouth by 32%.
Don’t just crank the humidifier to max. You’ll end up with water pooling in your mask or hose. That’s messy, uncomfortable, and can breed mold.
Mask Leaks: The Silent CPAP Killer
Leaking air isn’t just annoying-it’s dangerous. Dr. David White from Harvard says leaks over 24 liters per minute reduce treatment effectiveness. Your CPAP machine might still run, but it’s not keeping your airway open like it should.
Leak causes are almost always physical:
- Old or worn-out cushion. Silicone cushions degrade over time. Replace them every 3 months. If your mask feels loose even when tightened, it’s probably the cushion.
- Wrong size or style. If your mask pinches your nose or leaves red marks, it’s too tight-or wrong for your face. Try a nasal pillow, hybrid, or full-face mask. Fit matters more than brand.
- Loose headgear. Tightening straps too much causes leaks too. Over-tightening distorts the seal. The right fit? You should feel gentle pressure, not pain.
Here’s how to test your seal:
- Put on your mask and turn on the machine.
- Listen for hissing. That’s air escaping.
- Adjust one strap at a time. Start with the top strap, then the bottom, then the side straps.
- Stop when the noise drops. You don’t need to pull it tight enough to make your face hurt.
Most leaks are fixed with three adjustments or less. If it’s still leaking after that, try a different mask. ResMed, Philips, and Fisher & Paykel all offer free fit kits so you can test sizes before buying.
Pressure Too High? Too Low? Don’t Guess-Adjust Smartly
Pressure settings are not one-size-fits-all. Too high? You’ll feel chest pressure, struggle to exhale, or wake up gasping. Too low? Your apneas return, and you’re back to snoring.
Auto-adjusting CPAPs (called APAPs) like the ResMed AirSense 11 or Philips DreamStation 2 change pressure automatically based on your breathing. But even these need a good starting point. Many users are set too high initially-often at 14 cm H₂O or more-because doctors err on the side of caution.
Dr. Nancy Collop from Johns Hopkins says: “Pressure adjustments below 5 cm H₂O can dramatically improve comfort without compromising efficacy.” That means if you’re at 12 cm H₂O and it feels harsh, ask your provider to try 9 or even 8. Many people find relief with lower pressure, especially if they use expiratory pressure relief (EPR) or C-Flex, which lowers pressure when you breathe out.
Here’s what to do:
- Check your machine’s data. Most modern CPAPs track your AHI (apnea-hypopnea index). If it’s under 5, you’re doing well-even if pressure feels high.
- Don’t adjust pressure yourself. Manufacturer policies (like ResMed’s) say changing pressure beyond ±2 cm H₂O voids your warranty. Talk to your sleep specialist.
- Use apps like DreamMapper or ResMed’s myAir. They give weekly reports on your leak rates, pressure trends, and usage. Share them with your doctor.
- If you’re still uncomfortable after 2-4 weeks, ask for a pressure re-titration. A sleep study doesn’t need to be done in a lab anymore-many providers now offer home titration studies.
One user on Reddit, u/ExhaustedEngineer, went from 14 cm H₂O to 9 cm H₂O after complaining of chest discomfort. His AHI stayed below 3. He slept better than ever.
What You’re Probably Doing Wrong (And How to Fix It)
Most CPAP problems come down to three mistakes:
- Skipping mask cleaning. Oils from your skin clog the cushion. Wash it daily with mild soap. Replace cushions every 3 months.
- Not changing filters. Foam filters should be replaced every 30 days. HEPA filters every 90. Dirty filters reduce airflow and make the machine work harder.
- Waiting too long to get help. If you’ve had the same issue for more than two weeks, call your DME provider. ResMed offers 24/7 support with 97% same-day response. Don’t suffer in silence.
Also, don’t assume your mask fits just because it came with your machine. Face shapes change. Weight fluctuates. Hair grows. A mask that fit last year might not fit now.
When to Call Your Doctor
Some problems need professional help:
- Your AHI stays above 5 after 30 days of consistent use.
- You’re still waking up with dry mouth after trying a full-face mask and chin strap.
- Your machine shows frequent high leaks (over 24 L/min) even after replacing the cushion and adjusting straps.
- You feel dizzy, have headaches in the morning, or notice swelling in your face.
These could mean your pressure needs fine-tuning, your mask isn’t right, or you have another sleep issue like central sleep apnea. Don’t wait for your next annual checkup. Schedule a follow-up.
What Works Better Than You Think
Many people give up on CPAP because they think the machine is broken. But the real issue? It’s the fit, not the tech.
Here’s what users who stick with CPAP do differently:
- They try 2-3 masks before settling.
- They clean their equipment daily.
- They check their data every week.
- They ask for help early.
According to ResMed’s 2023 patient data, 78% of users master basic troubleshooting within 14 days. That’s not magic-it’s consistency.
CPAP isn’t perfect. It’s bulky. It makes noise (though newer models are as quiet as a whisper-25-28 dB). But it’s still the most effective treatment for obstructive sleep apnea. It reduces apnea events by 70-90%, cuts heart disease risk by 30% over five years, and improves focus and mood for 85% of users.
You don’t have to love your CPAP. You just have to make it work.
Frequently Asked Questions
Why does my mouth feel dry even with a humidifier?
Dry mouth from CPAP is usually caused by mouth breathing, not low humidity. Air escapes through your mouth, pulling moisture from your throat. Switching to a full-face mask or using a chin strap fixes this for most people. Increasing humidifier settings alone won’t help if air is still leaking out your mouth.
How often should I replace my CPAP mask cushion?
Replace your mask cushion every 3 months. Silicone breaks down from skin oils, cleaning products, and daily use. A worn cushion won’t seal properly, leading to leaks and reduced therapy effectiveness. Most DME providers recommend replacement every 90 days-don’t wait until it cracks.
Can I adjust my CPAP pressure myself?
No. Most manufacturers, including ResMed and Philips, state that changing pressure settings beyond ±2 cm H₂O voids your warranty. Pressure needs to be set based on your sleep study results and ongoing data. If you feel your pressure is wrong, contact your sleep specialist or DME provider-they can review your usage data and schedule a re-titration if needed.
Is a chin strap safe to use with CPAP?
Yes. Chin straps are a safe, non-invasive way to keep your mouth closed during sleep. They’re especially helpful for people who breathe through their mouth while using a nasal mask. Use a soft, adjustable strap-not something that pulls too tight. Many users report immediate relief from dry mouth after starting one.
Why is my CPAP machine so loud?
Modern CPAP machines like the ResMed AirSense 11 and Philips DreamStation 2 operate at 25-28 decibels-quieter than a whisper. If yours sounds louder, check for leaks, a dirty filter, or a damaged hose. Air escaping through a bad seal makes noise. Clean your filter, replace the hose if it’s cracked, and ensure your mask fits properly. If it’s still loud, the machine may need servicing.
Next Steps: What to Do Today
Don’t wait for your next doctor’s appointment. Take action now:
- Check your mask cushion. If it’s older than 3 months, order a replacement.
- Wash your mask and hose with mild soap tonight. Dry them completely.
- Look at your CPAP app. Is your leak rate above 24 L/min? Are you getting 4+ hours of sleep per night?
- Try a chin strap tonight if you wake up with a dry mouth.
- Call your DME provider. Ask if you can get a different mask size or style for free.
CPAP therapy works when you make it work. It’s not about perfection. It’s about small, consistent improvements. Fix one thing this week. Then another next week. You’ll sleep better than you have in years.
Adam Hainsfurther
November 25, 2025 AT 07:26Worth every penny. Don’t overcomplicate it.
akhilesh jha
November 25, 2025 AT 17:26Jeff Hicken
November 26, 2025 AT 07:37Vineeta Puri
November 28, 2025 AT 03:06Victoria Stanley
November 30, 2025 AT 00:52Andy Louis-Charles
November 30, 2025 AT 22:37