DC/DC Converter 24V/90W for S9™ CPAP device

£59.00 Plus VAT at applicable rate. Excluding delivery.
Free delivery for orders over £150
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Choose the ResMed DC/DC Converter to operate your S9 CPAP therapy device and accessories using a 12V or 24V DC power source. This DC/DC converter allows you to connect your S9 therapy device, heated humidifier and heated tube to a car, truck, caravan, boat or other vehicle equipped with a suitable power source.  

S9 device not included; shown for illustrative purposes only. 

Products available on this store are intended for sale in the United Kingdom only. 


The S9 DC/DC converter can be used to power ResMed S9 CPAP devices and accessories from a vehicle’s auxiliary/accessory power outlet (‘cigarette lighter’) or 12V/24V battery. By powering your S9 therapy device, H5i™ heated humidifier and ClimateLine™ heated tube from a car, truck, caravan or boat battery, you can enjoy the benefits of effective therapy alongside the pleasure of an active lifestyle. 

  • Practical: power your therapy device from a car, boat or other vehicle equipped with a 12V or 24V DC power source or a suitable battery. Supplied with a Cigarette Plug Lighter End and Croc Clip Adaptor. 
  • Functional: can be used to operate an S9 CPAP device, including an H5i heated humidifier and ClimateLine heated tube. 
  • Liberating: your therapy device is no barrier to enjoying travel or vacations off the beaten track.  

Please take care not to flatten the vehicle’s battery when using this device.  

Please refer to the user guides for relevant information related to any warnings and precautions to be considered before and during use of the product. 

Ask your doctor about using this medical device to treat your obstructive sleep apnoea.

Technical details

Manufacturer ResMed
Included in Package DC/DC Converter for S9, user guide
Warranty 12 months
Length (connector to connector) 3m
Fuse rating F 20A L, 250 V (fast blow, low breaking capacity)
Input 12 V/24 V 13A/6.5A
Output 24 V 3.75A


 If necessary, wipe the outside of the converter with a clean, damp cloth. 



Most orders are delivered within 3-5 working days, however please allow up to 10 working days.

  • Delivery is usually within 5 working days, via Royal Mail*
  • Online orders cannot be expedited once placed. If you require an order URGENTLY, instead of ordering online please order by phone on 0800 917 7071 (available Monday to Friday 09:00-17:00)
  • Online orders cannot be amended or cancelled once placed, however you can return products within 14 days for a full refund, please refer to Section 5 within our Terms & Conditions for full information
  • Orders are sent via Royal Mail. If your package is too large to fit through a letterbox or a signature is required, it will be taken to a local Royal Mail sorting office for you to collect at your convenience
  • For full information on Returns, please click here

* Under normal conditions. Orders cannot be expedited after they are placed online.


VAT relief is available on certain products in the ResMed online shop.

In the UK, customers are entitled to buy these products VAT free if they are disabled and/or have a chronic sickness, provided the product relates to their disability or sickness and is for personal use.

Moderate to severe obstructive sleep apnoea is considered a chronic sickness, along with other diseases or conditions. This means that, if you have moderate to severe OSA or another chronic sickness, you may be able to buy some products from our online shop VAT free. 

Eligible customers should check the box marked, I am entitled to VAT relief for disabled people, before adding any item(s) to their basket.  

For further information, please click here to read more, or check the HMRC Vat Notice 701/7 web page. 


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Delivery within 3-5 working days

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