After my wife asked me last week, “why isn’t my CPAP using water anymore?”, I finally thought to write a blog on the topic. She would wake up and pull her humidifier chamber in the morning, only to find that the water level had not changed at all. This happens from time to time, usually as seasons change, and most likely is not an issue at all. So, what is going on?
Why isn’t my CPAP using water?
Most modern CPAP machines are built with a hydrometer and thermometer that constantly monitor your room’s ambient conditions. The CPAP is doing this because it is trying to avoid excess condensation. Better known as “rainout”. That happens when the CPAP adds more humidity than the air in your room can hold. When that happens you literally end up with rain inside your tubing. By monitoring the humidity and the temperature the CPAP tries to minimize the chances of adding too much humidity. That means that if your CPAP is detecting that the room is too cold or that the room already has too much humidity, then it will not add any additional humidity. In turn, your water chamber will still be full in the morning.
How can I tell if the Humidifier is actually working?
The first thing to determine if the humidifier is actually doing its job or not is to ask yourself a simple question: “Do I feel dried out?”. If your answer is no, then you don’t have a problem. Just because there is no change in water level, doesn’t mean that there is an issue. If your answer to that question is yes, then the first thing that you should do is increase the humidity setting. This setting should be located in your patient menu. If you have increased the humidity to the max and there is still no change, then we need to bypass the check system. We detail how to do that below. Additionally, on some newer CPAP models like the ResMed AirSense 11, you can see on the sleep report whether or not the humidifier is working correctly.
How can I add more humidity without rainout?
So maybe you are dried out because the CPAP will not add enough humidity. In that case there is a pretty simple solution. You can add heated tubing to your humidification system. Almost all of the newer CPAP models have an available heated tube. ResMed has one called ClimateLine and Respironics has heated tubing for theirs as well. These heated tubes will keep a controlled environment from the outlet of the CPAP all the way to your CPAP mask. This means that the ambient humidity and temperature conditions in your room will not matter. Once the heated tube is added you can increase humidity level to a comfortable setting without the risk of rainout or the CPAP capping your humidity. We also have a great Blog on the rainout issue as well.
Things to consider about your CPAP Humidifier:
Empty the water chamber daily– Regardless of whether or not your CPAP used any water, you still need to empty it and allow it to dry out daily. This will prevent mold, mildew, and bacteria from growing in the stagnant water.
Stick to distilled water– As the water evaporates it leaves behind the minerals that were in the water. These minerals can be harmful to the CPAP parts. Causing corrosion as well as a breeding ground for all sort of nasty things.
Clean the water chamber at least weekly– If there is one, most-important thing, on your CPAP that can make you sick, it is the water chamber. You wouldn’t fill your chamber with pond water so don’t let the water chamber turn in to a pond. Clean it at least once per week with mild soap and water.
When do I change my Water Chamber?
Changing out your Humidifier Water Chamber is completely dependent on how well you are maintaining your water chamber. If you are emptying it daily and washing it at least once per week, then you may get as much as a full year out of the tank. If you are using tap water, well water, or aren’t cleaning the water chamber then you may get as little as 3 months. On average it is best to change out your water chamber about every 6 months.
Signs that it is time to change out your CPAP water chamber:
Leaking water tank and/or water on your nightstand.
