Table of Contents Hide
- What is sleep apnoea?
- What is a CPAP machine?
- Power Requirements
- Mode of operation
- 12V compatibility
- 240V inverters
- Buying a CPAP machine for caravanning
- Power requirements
- Inverter Power
- Noise level
- Pressure testing
- CPAP machines
- Don’t let sleep apnoea stop you from camping
Okay, you’ve been diagnosed with sleep apnoea and you’ve been told you have to get a CPAP machine. You may be wondering what to do next. Don’t worry, help is at hand with our guide to choosing a CPAP machine, so you can go caravanning and camping with sleep apnoea.
What is sleep apnoea?
Sleep apnoea is a sleep disorder characterised by pauses in breathing or instances of shallow or infrequent breathing during sleep. Each pause in breathing, called an apnoea, can last for several seconds to several minutes, and may occur, by definition, at least five times in an hour.
What is a CPAP machine?
Continuous positive airway pressure (CPAP) machine is a form of ventilator that applies mild air pressure on a continuous basis to keep the airways open in a patient who is unable to breathe spontaneously on his or her own. It consists of a small pump which may have a humidifier incorporated into it or as a separate attachment, an air hose and a delivery mask of some type, usually either a full-face mask, nasal pillow mask or micro nasal mask or tubes. These are the most effective treatment for sleep apnoea.
Power consumption figures should be noted on the power supply
Of all CPAP machines on the market, the majority operate on 240V mains power however, there are a number that have a 12-volt DC alternative power source, suitable for RV use. There are also a handful of smaller, portable CPAP machines that are battery operated. These are ideal for mobile use and are suitable for use in tents or any other environment where power is restricted or non-existent.
My old Resmed 9 could be used without the heater/humidifier attached, reducing power consumption
Mode of operation
Most modern CPAP machines have various modes.
- Normal – Where air is pumped at ambient temperature and humidity.
- Heated Air – Where the air entering the patient is heated to a set temperature via a heated air hose. The use of the heater will increase the power requirements of the unit.
- Humidified Air – Some users find the pumped and heated air dries out their nasal passages. Units with a humidifier use a small tank of water to increase the humidity of the pumped air eliminating the drying effect. Some portable CPAP machines draw extra moisture from the ambient air to increase humidity. These functions use more power again.
Some CPAP machines can be supplied with alternative power sources including 12-volt DC. They are usually supplied with an automotive 12-volt cigarette lighter plug. It’s important to note most CPAP machines operate at around 24 volts, meaning the 12-volt power supply is actually a DC-DC converter. These raise the supply voltage and will draw higher amps than a straight 12-volt system.
You will need a decent inverter and battery system
As with any other 240-volt appliance, CPAP machines can be powered by a 240-volt inverter. CPAP machines are very sensitive pieces of equipment that contain sophisticated electronics. Therefore, if they don’t have a 12-volt option, they must be powered using a pure sinewave inverter when mains power is unavailable.
Buying a CPAP machine for caravanning
When choosing a CPAP machine that is suitable for caravanning and camping, there are a few things to look for:
There’s not a lot of room next to the bed. Make sure yours will fit in the space available
There is precious little space to place a CPAP machine around the beds in our caravans and motorhomes. Its either going to have to sit on the bedside table or in the cavity under the wardrobe, if your RV has one. Make sure you check the dimensions of any unit before you buy it to ensure it will fit in the space you intend for it. We had our manufacturer fit both mains and inverter 240V outlets near my side of the bed to power my CPAP machine.
CPAP machines don’t use a lot of power in normal operation but if you use the heater and humidifier, their power requirements increase substantially. If you’re wanting to use your CPAP machine while free-camping, you’re going to need to know how much power it uses. All models are different, but you can expect up to 5-amp hours per hour in full heater and humidifier mode. That will drain 40-amp hours from your batteries if you sleep for eight hours. If you use your RV’s lights, pumps, TV, fridge or other 12V appliances, you’re going to flatten a modest battery system in no time.
Ensure the CPAP machine has the option to disable the heater and humidifier functions. This will allow you to run the unit consuming the least amount of power.
This Xantrex inverter monitors current draw from the battery
When running from an inverter, check the specifications of the unit. If it draws two amps at 240 volts, the corresponding drain on your batteries will be approximately three times that amount or six amp-hours per hour.
The vast majority of new CPAP machines are almost completely silent when operating, however, the smaller the unit, the noisier the pump will be. As a guide, 50db is the equivalent noise level inside a quiet restaurant. Normal office chatter is about 60db. The interior noise of a car is about 80db. Always check the specifications to see if the noise level will be an issue for you or your partner.
Always ensure the CPAP machine is covered for your intended use, especially if you want to power it from an inverter. Some manufacturers will not warranty their units if a fault occurs when operating from an inverter.
CPAP machines do not last forever and it is important to know the expected lifespan of your unit. Most have a five-year lifespan before the motor operating the pump will either require replacing or servicing. When the motor approaches the end of its life, it will need to work harder in order to maintain the set air pressure level, increasing power consumption.
Like most electrical and mechanical devices, CPAP machines require a degree of regular maintenance in order to perform to specification. Considering they are a medical device, it is vital you do not neglect their maintenance.
Most CPAP machines have at least two filters. One will be for air coming into the unit. The other will be in the mask. There may be others. Check the manual to identify what filters need regular replacing. Always keep a few spare filters with you as you may find you’ll go through more of them if you’re camping in dusty conditions.
Wipe down the CPAP machine with a damp cloth to remove surface dust. You may need to remove calcium build-up from the humidifier water tank. Vinegar and a little bicarb soda make an excellent cleaner for this purpose. If you’re using a mask, wash the straps regularly and disinfect the surface of the mask with an alcohol wipe.
The last thing you want is for the motor in your CPAP machine to fail in the middle of the night. Trust me, I’ve had this happen and it’s no fun for you or your partner. Take your CPAP machine to a dealer regularly and have them pressure test it to ensure it is in top condition.
Don’t let sleep apnoea stop you from camping
Being diagnosed with sleep apnoea is certainly on the lower end of the severity scale of medical issues you may have to endure in your life. Once you get used to using a CPAP machine, you’ll wonder how you ever survived without one. Yes, they are a bit clumsy and they need a bit of power to operate but once you’ve got all that sorted out and you settle into a routine, they don’t negatively impact your caravanning and camping experience. The technology is improving all the time, and CPAP machines available today are far more suited to a mobile lifestyle to those of just a few years ago.
If you’re about to purchase a CPAP machine, talk to your sleep therapist about what options they recommend that will suit you and your needs, especially if you intend to use one while caravanning.