Signs Your CPAP Machine Is Not Working or Needs Adjusting

Continuous positive airway pressure (CPAP) is widely regarded as the best treatment available for obstructive sleep apnea, a breathing disorder that affects millions of people. It is highly effective when properly used and the CPAP machine is kept in good working condition.

There are ways to know if your CPAP device has become less effective because it's not working properly. It may need to be adjusted or replaced entirely.

This article explains some of the reasons why a CPAP machine is no longer providing you with the best results. Better still, it offers tips that may fix the problem in many cases.

Woman lying in bed using a CPAP machine
Juanmonino / Getty Images

The CPAP Machine Just Isn't Working

If the machine simply does not turn on, it clearly is not working properly. When plugged in, most CPAP machines can be turned on with the push of a button. If you place it on a specific setting, some machines will even start working automatically when you breathe into your connected mask a few times.

If the CPAP stays off or there is no airflow at all, you should take it to your equipment provider. They can determine if the device needs to be repaired or replaced. This is often the case when it has stopped working after it is dropped.

There can be other signs that something is amiss with your CPAP machine. That's because there are water and heating systems that can malfunction, too, apart from the power supply. Here are a few to consider.

  • Your heated humidifier tank should be refilled about once every two to three days. If that's not the case, the temperature and humidity settings may need to be adjusted. But if the water never goes down, the humidifier may not be working at all.
  • The hot plate under the water chamber may not be warming up. There is still some evaporation as the air passes over the water but it's at a much slower rate. This may mean that the heating element isn’t working.
  • If the air feels uncomfortably cool, this is further evidence that the machine is not working.
  • Water may condense inside heated tubing in some machines that have them. This tends to mean the humidity setting is too high, the tubing is not connected right, or it's just not working properly.
  • The machine may also be more noisy and it seems to provide less airflow than it did before.

You're Still Snoring or Having Apnea

Snoring should never occur when the CPAP pressure is set properly. That's because the constant flow of air will keep the airway open and prevent its collapse. It also stops the airway tissue vibrations that cause snoring.

If you are snoring with your CPAP mask on, and the mask is not leaking, talk to your healthcare provider. The pressure likely needs to be increased to be fully effective.

You may have pauses in your breathing or episodes where you wake up gasping and choking even while using your CPAP machine. If these events are confirmed, it's likely the pressure setting needs to change.

The apnea-hypopnea index (AHI) counts the number of breathing disruptions that occur per hour of sleep. You can sometimes find an AHI display on your machine or monitoring apps. If it is greater than 5 when you wake up, then the pressure should be increased.

If you have any of these problems, you should discuss them with your sleep specialist.

You Feel Worse

Some people who start using a CPAP machine will see benefits in a matter of days or weeks. Signs that CPAP treatment is working may include:

  • Fewer awakenings 
  • More refreshing sleep
  • Decreased daytime sleepiness
  • Better concentration
  • Improved short-term memory or mood

Over the long term, other conditions associated with untreated sleep apnea may also improve. They may include high blood pressure, heart failure, or diabetes.

Symptoms of sleep apnea are usually what lead to CPAP use. If the same symptoms return, this may mean the machine is not delivering the best possible results. You should talk this issue over with your healthcare provider.

When there is a problem, people using CPAP will most often complain that their excessive daytime sleepiness has returned. They again need to have long or frequent naps. Possible causes include a mask leak or not enough treatment pressure.

Other changes in your health or lifestyle may cause your symptoms to return. That may mean your CPAP settings need to be adjusted. Among them are:

  • Weight gain
  • Alcohol use near bedtime
  • Advancing age


One way to tell if your CPAP machine no longer works well is if you experience the same symptoms you once had before using it—for example, if the snoring returns, your AHI index rises, or you no longer feel rested during the day. It means it's time to reevaluate how the CPAP machine is working for you.

Your CPAP Machine Is Aging

Unfortunately, CPAP machines do not last forever. Your machine may start to make a funny noise, become harder to operate, or won't generate the same pressure as before, That may mean it's time to replace it.

In general, most insurance companies will pay to replace the CPAP machine every five years.

These devices do have some degree of built-in obsolescence, meaning that they are not meant to work forever. They will gradually begin to fail and you'll need to replace it with a new device.

If your CPAP machine is old enough and it's no longer working well, a replacement is due. Fortunately, next-generation models often have improved features. The new machines often are quieter and easier to use when compared to old equipment.


Your CPAP machine is only as good as the health benefits it provides. When it's working well, you'll feel far more rested and your symptoms of sleep apnea and snoring will be resolved.

But when the device isn't working properly, your symptoms may return. There are several reasons for why the CPAP machine may be failing. The problem can be with the power, tubing, or heating element. Or it may just be that an old machine needs to be replaced.

In other cases, changes in your health or lifestyle may simply mean that your settings need to be changed to ensure you're getting the right amount of pressure. If your apnea symptoms return, talk with your sleep specialist to find out the cause and solutions.

A Word From Verywell

If you believe that your CPAP machine is not working properly, don't suffer in silence. Call your equipment provider or sleep specialist and get your treatment back on track.

2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Cao MT, Sternbach JM, Guilleminault C. Continuous positive airway pressure therapy in obstuctive sleep apnea: benefits and alternatives. Expert Rev Respir Med. 2017;11(4):259-272. doi:10.1080/17476348.2017.1305893

  2. Konecny T, Kara T, Somers VK. Obstructive sleep apnea and hypertension: an update. Hypertension. 2014;63(2):203-9.

By Brandon Peters, MD
Brandon Peters, MD, is a board-certified neurologist and sleep medicine specialist.