Frost Wash, a Revolution in Heat Pump Cleaning Technology

The Hitachi Heat Pump  ‘S’ Series range offers many innovative and unique features. As part of Hitachi’s commitment to advancing our products, Hitachi saw a clear, unmet need of cleanliness. We knew we could design a solution that set our products apart.


Air is constantly travelling across the surface of your heat pump heat exchanger. Dust, mold and bacteria can accumulate, leading to reduced unit performance and perceivable odours. A dirty heat exchanger will decrease your indoor air quality as additional air particles such as dust and mould are circulated around the room. This can increase the likelihood of breathing difficulties being aggravated.


Keeping the heat exchanger clean is the key to better quality air.


Frost Wash addresses an issue that has long stumped the air conditioning industry – how to effectively and efficiently clean the inside of room air conditioning units.


While cleaning the filters inside air conditioners may be a familiar process to our customers, cleaning inside the machine itself has usually required professional services.


Frost Wash successfully achieves a 91% reduction of bacteria and an 87% reduction of mold in your unit after a single wash.


The Frost Wash technology works by cooling down the heat exchanger to -15°, forming a thin layer of frost from the moisture in the air. While the frost is being formed, it lifts dust particles, mold and bacteria off the heat exchanger and traps it.




Once an adequate layer of frost has been formed, the system then melts the ice, flushing away the trapped dust particles, mold and bacterially hygienically through the drain pan. The unit then thoroughly dries the surfaces inside the unit before resuming normal operation.



A clean heat exchanger not only keeps your unit operating at optimal efficiency, but also keeps the air in your home fresher and cleaner.


Frost Wash received an overwhelmingly positive response when it launched in Japan, receiving the “Excellence Award” by the Japan Electrical Manufacturers Association in 2018.


Frost Wash is now available in all 'S' Series models. Contact your local Hitachi Installer for product enquiries here.



by Hitachi
14 Jan 2020