CPAP Machine Troubleshooting Guide

In most instances, you shouldn’t have any major issues with your CPAP machine if it is brand new. However, every now and then you might experience a problem with an older machine that requires replacement or repair. Use the quick checklist below to jump to the symptom that matches what you’re experiencing.

Quick CPAP Troubleshooting Checklist

Is your CPAP machine acting up? Identify your problem below to find the solution:

• Machine won't turn on: Check power connections first. If using a modern touchscreen model, performing a 'hard reset' by unplugging for 60 seconds can often resolve software freezes.
• No Airflow: Check for a clogged filter or a twisted hose.
• Air feels too cold: If air feels too cold, enable 'Climate Control Auto' if your machine supports it; otherwise, manually increase tube temperature or humidity.
• Screen displays an error code: If an error code appears, check your machine’s synced smartphone app for an interactive troubleshooting guide and a direct link to the manufacturer’s support.
• Data not syncing: Check Bluetooth pairing and Airplane mode.
• Machine is noisy: A whistling sound usually indicates a mask leak or a water chamber that isn't fully inserted.
• Humidifier not working: Check settings, reseat the chamber, and test for heat before replacing parts.
• Pressure feels too high: Enable Ramp and exhalation relief (EPR/Flex), and check for mask leaks.
• Troubleshooting Connectivity: If your sleep data isn't syncing, ensure 'Airplane Mode' is off and your machine's Bluetooth is paired within range of your phone.

How Do I Know If My CPAP Machine Is Broken?

Like any machine, CPAP machines can break down or wear out over time. If the machine does not turn on or there is no airflow, then this is a case for a service call.

Most importantly, if your daily sleep report consistently shows an AHI (Apnea-Hypopnea Index) above 5.0 despite good mask fit, your machine may need pressure recalibration or replacement. If you are still snoring at night or experiencing daytime symptoms of sleep apnea, then you may need a new machine.

Can CPAP Machines Be Repaired?

CPAP machines can be repaired. Some companies will come to your home to service the machine. However, a repair can be costly. It's important to know and check your warranty. You may be eligible for free repair or replacement. Most CPAP machines have a two-year manufacturer’s warranty. If your CPAP machine is past warranty eligibility, then the cost of repair may not be worth it. Most CPAP machines should be replaced after three to five years. You may also find that purchasing a new machine is a better and more affordable option.

CPAP Machine Troubleshooting

CPAP Humidifier Not Working? Try These Fixes First

If your humidifier isn't using water or the heating plate remains cool, try these troubleshooting steps before purchasing a replacement:

• Check the Settings: Ensure your humidity level isn't set to zero or “Off.” Adjust it to a higher setting (typically 3-5) and test for one night.
• Inspect the Heater Plate: Remove the water chamber and look at the metal plate underneath. If it is dirty or corroded, clean it gently with a damp cloth to ensure a proper connection.
• Reseat the Chamber: If the water tank isn't pushed in all the way, the machine may disable the heater for safety. Remove and firmly re-insert the chamber.
• Test for Heat: Turn the machine on “Preheat” (if available) or run it for 5 minutes. Carefully touch the bottom of the water chamber. If it is still cold, the heating element may be faulty.

If you’ve tried the steps above and the humidifier still isn’t heating or using water, the humidifier components may be failing and it may be time to consider repair or replacement.

Why Does My CPAP Air Pressure Feel Too High?

If you feel like the air is blowing too hard or you are struggling to exhale against the pressure, your machine likely isn't broken—it just needs an adjustment.

• Enable the “Ramp” Feature: This setting starts your machine at a low pressure and gradually increases it over 20–45 minutes, allowing you to fall asleep before the full pressure hits.
• Check Exhalation Relief (EPR/Flex): Most modern machines (ResMed, Philips) have a setting that drops the pressure slightly when you exhale. Ensure this feature is turned On.
• Check for Mask Leaks: Surprisingly, a leaky mask can cause the machine to blow harder to compensate for the lost air. Tighten your headgear to ensure a proper seal.

If high pressure sensations continue after adjusting comfort settings, contact your provider to confirm your prescription settings are correct. Avoid changing your prescribed therapy pressure without clinician guidance.

Check Filters and Tube

If the airflow from your CPAP machine seems reduced, then you should check your filters. They may need to be changed. Follow the manufacturer’s guidelines for maintaining filters.

Another common problem for reduced airflow may be damaged tubing. Check your tubes for cracks or leaks. Air is passing through these holes rather than to your mask, which reduces air pressure. If you find flaws in your tubing, then it’s time for tubing replacement.

Check the Air Passage

If you notice there is less airflow or your CPAP machine seems too noisy, there may be a clog. Look for obstructions anywhere along the air passage, from hose to mask. Cleaning your mask and hose regularly can also help eliminate the possibility of blockages. Follow your CPAP machine manufacturer’s guidelines for regular cleaning to help maintain consistent airflow and CPAP machine performance.

Dry Your Machine to Avoid Condensation

If you notice condensation in your mask or tubing, this is known as rainout. Rainout occurs in CPAP machines with heated humidifiers. As the air travels through your tubing, its temperature drops rapidly.

If the air feels too cold, check if your machine has a “Climate Control Auto” feature (common on ResMed AirSense 11 and Luna G3). This automatically balances tube temperature and humidity. If not available, manually increase the tube temperature or try wrapping your hose to keep it warm.

CPAP Machine Not Working or Won’t Turn On? Start Here

If your CPAP machine won’t turn on or seems to stop running unexpectedly, work through these quick checks:

• Check the power connection: Ensure the power cord is firmly seated in the machine and in the power brick (if your model uses one).
• Try a different outlet: Plug into an alternate outlet to rule out a failed outlet or one controlled by a wall switch.
• Inspect the cord and brick: Look for kinks, fraying, or visible damage. If anything looks worn, stop using it and replace the damaged part.
• Perform a hard reset: If using a modern touchscreen model (like AirSense 11), the screen may be frozen. Unplug the machine for 60 seconds to clear software glitches, then plug it back in.

If the machine still won’t power on after these steps, you may need a service evaluation or replacement power supply.

Troubleshooting Connectivity & Syncing Issues

In 2026, data sync failures are a common complaint with "Smart" CPAPs. If your sleep data isn't appearing in your app:

• Check Airplane Mode: Ensure Airplane Mode is turned OFF. This mode disables all wireless communications.
• Re-Pair Bluetooth: Toggle Bluetooth off and on in your phone settings. If that fails, "forget" the device and re-pair it using the code on your CPAP screen.
• Check Signal Strength: If your machine uses cellular data, ensure it is not located in a basement or area with poor reception.

Screen Displays an Error Code

If your CPAP screen displays an error code, check your machine’s synced smartphone app (such as myAir or LightKnowing). Modern apps often provide interactive troubleshooting for specific codes. If the error persists, consult the table below or contact your equipment provider.

Common Error Codes Reference

CPAP Machine Is Noisy

If your CPAP machine is getting noisier over time, first check for simple causes like a mask leak, loose connections, or a water chamber that isn’t fully inserted. Also inspect your hose for small leaks or cracks. If the noise persists, the motor may be wearing out and you may need service or replacement.

Replacing Your Broken CPAP

Warranty Period

Most CPAP machines are covered by a two-year manufacturer’s warranty. If you experience any problems with your CPAP machine within the warranty period, contact the manufacturer. The contact information can be found in your user’s manual or online at the manufacturer’s website.

When your CPAP machine is passed its warranty, it is usually time to be replaced.

Prescription

When replacing your old CPAP machine, be sure that your new machine follows the same recommendations from your doctor. Double-check your prescription. You will want a CPAP machine that meets the air pressure requirements you need for your CPAP therapy.

When it comes time to replace the machine, it’s also a good idea to check with your doctor to see if there are any changes in your prescription.

Check for Insurance

Some health insurance providers will cover the cost of a CPAP machine replacement. Talk to your health insurance company or review your policy to see if durable medical equipment such as CPAP machines is covered, if only partially. It may be an opportunity to save money on a CPAP machine replacement.

Find the Best CPAP Machine

Always be considerate and thorough when selecting a CPAP machine. Find one that fits all of your CPAP therapy needs. Here are a few things to consider.

• A portable CPAP machine if you travel frequently, so you can stay CPAP compliant on the go.
• A heated humidifier to provide warm, moist air if you experience a dry throat or nose from CPAP.
• A CPAP machine with a ramp feature if you have difficulty with your prescribed pressure setting.

Where Can I Buy A CPAP Machine?

You can purchase CPAP Machines online or in-store at The CPAP Shop.  Our knowledgeable staff can help you choose the best replacement CPAP machine for your needs.  You can find CPAP machines from top manufacturers like ResMed and others.