+44 203 286 8189 steve.jones@westside-int.com

Dehumidifier for very small  spaces

Rosahl is a micro-dehumidifier for very small spaces and enclosures where maintenance free drying is an important factor. Rosahl is a family of compact electronic dehumidifier that use ionic membrane to electrically dehumidify enclosures from less than two litres in size up to 4m³. The PD3 model is 75%smaller than a regular AA battery, and is the world’s smallest electric dehumidifier in commercial use.

The PD3 version uses an M12 fine pitch (0.5mm) screw thread mounting. As an alternative the RD version uses four mounting screws. it is available for mounting on the inside of the container (RD3), or in the case or the RD4, on the outside. Larger sizes are available for up to two cubic metres (280 cu ft), and for larger enclosures multiple units are used.

Low energy dehumidifier.
Rosahl is a low energy dehumidifier designed for use in steady state environments, that are closed to the ingress of further moisture. They suit storage cabinets for moisture sensitive devices, CCTV cameras, museum cabinets and a wide range of similar applications.
The Rosahl membrane is a solid state dehumidifier that requires a 3 Volt D.C supply. It has no moving parts and is therefore silent and vibration free in operation. It is also very economical to run 24/7 if required, and requires no maintenance.

See how Rosahl works here.


Advantages of Rosahl micro-dehumidifiers


Silent & vibration free

Rosahl dehumidifiers have no moving parts so there is no noise or vibration when operating.


Maintenance Free

Rosahl requires no regular maintenance, reducing total cost of ownership (TCO)

Long Operating Life

Rosahl uses a solid-state ionic membrane giving it a long service life and low operating costs

Low Energy Footprint

Rosahl membranes operate at 3V d.c. and use a very low average operating current to save energy


Ultra Compact

75% smaller than an AA battery, Rosahl can be used in enclosures from 250ml

Operates Below Freezing

Tested to -20°C, Rosahl may be used for internal and external applications

No moving parts

Rosahl dehumidifiers have no moving parts so there is no noise or vibration when operating and nothing to wear our or service

Solid-state membrane

Solid-state polymer electrolyte (SPE) provides reliable operation with low average power consumption and a long service life

No liquid water

The process works at a molecular level and no liquid water is involved, so no cleaning or drainage are needed