Frequently asked questions about Hitachi Cooling & Heating products, technical aspects and policies.


Frequently asked questions about Hitachi Cooling & Heating products, technical aspects and policies.

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Find answers to frequently asked questions, and broaden your knowledge of Hitachi air condioner product and related technical aspects and issues.
Product inquiries
airCloud Go

Frequently asked questions: All

Where can I view or download a catalogue of the different products you offer and their technical details?

You can check our dedicated Downloads section where you will be able to search and download catalogues, brochures and technical data about the products we offer.

Who do I contact if I have an issue with a Hitachi HVAC product?

Vist our Contact Us page and fill in the simple form so that we can ensure that your request is directed to the correct team.

How do I determine the warranty period for my mini-split, mini-VRF and VRF products?

Warranty periods for these products are based on registration and commissioning. To learn about specific warranty periods for your product based on product type, visit our Training and Warranty page.

How can I activate FrostWash?

All Hitachi air conditioners that embed FrostWash feature have a dedicated FrostWash button button (1) on the remote control. You can simply press FrostWash button button to activate the self-cleaning process.


If your air conditioner is connected to airCloud app, you can also start FrostWash from your phone, while you’re away.


Some Hitachi air conditioners with a human presence/motion sensor also offer automatic activation of FrostWash when the air conditioner has been running for over 42hours (2) and the room is vacant (referred to as ‘FrostWash Auto’ in technical documentation). To enable and disable the automatic activation of FrostWash, press and hold simultaneously FrostWash button button and [Timer] button (3).


(1) Symbol design may vary per remote control.
(2) Cycle duration may vary in some regions.
(3) Read your remote controller’s manual to see how to disable automatic activation of FrostWash.

How often shall I run FrostWash?

It is recommended to run FrostWash every 42hours* of air conditioning operation (whether cooling, heating, dry or fan mode).


*Cycle hours may vary per region. Please read your air conditioner’s user manual to confirm the recommended frequency of FrostWash.

How long does FrostWash take?

FrostWash process may take up to 145min to complete. It can also be shorter, depending on the conditions of the air (humidity and temperature) and level of dirt accumulated inside your air conditioning unit.

Is there a limit to using FrostWash?

You can run FrostWash as many times as you desired, for unlimited period, during your air conditioner’s life. Do not open windows or doors during FrostWash operation, or water might condense on the air deflector and drips down onto your home floor and furniture.

Will the room get cooler during FrostWash?

FrostWash is designed to freeze and dry the heat exchanger coil without affecting the room temperature. During the FrostWash process, the louvers of the air conditioner remain closed, to avoid air circulation through the unit.

How is the detached dirt evacuated?

Resulting from the melting process, the detached dirt and microorganisms mix with the melted water and is taken away through the regular condensate drain.

Can FrostWash be processed while my air conditioner is operating?

FrostWash requires the air conditioner to be turned off. Be sure you run FrostWash when the ON/OFF timer is off.

Does FrostWash make some noise?

Hissing, fizzy or squeaking noise may occur during FrostWash operation.

My Hitachi air conditioner does not have heating mode but it has FrostWash. How will the frost melt?

For cooling-only air conditioners: the melting is done by letting the coil melt naturally at the room temperature.

I tried starting FrostWash but it does not work.

FrostWash cannot be operated outside of the following conditions.


• FrostWash can perform when the outdoor temperature is between 70°F to 109°F.
• FrostWash can perform when the room’s indoor temperature is between 50°F to 90°F.
• FrostWash can perform when the room’s humidity level is between 30% to 70%.
• FrostWash cannot be operated again within 60 minutes after the end of the previous operation.


If these conditions are met and FrostWash does not work, please consult your Hitachi Cooling & Heating representative.

Will the heat exchanger coil develop rust or corrosion due to FrostWash?

Our air conditioners’ coils are subjected to corrosion tests to ensure they can sustain FrostWash over many years. After repeated & accelerated freezing test on the heat exchanger (equivalent to approximately 8 years of usage), the resistance of the coil was verified, thanks to hydrophilic properties of the fins.

How can I stop FrostWash during the self-cleaning process?

FrostWash can be stopped before the process is completed. Depending on the remote controller, FrostWash can be stopped by pressing  button or [stop] button*.

*Read your remote control’s manual to confirm which button you need to press.

Can all Hitachi air conditioners connect to airCloud Go?

Not all Hitachi air conditioners can connect to airCloud Go.
Our offerings of Hitachi residential air conditioners include three types, varying per region:

  • Type 1: Hitachi air conditioners requiring additional airCloud Go wifi adapter (available as an accessory)
  • Type 2: Hitachi air conditioners ready to connect, with embedded wifi connectivity
  • Type 3: Hitachi air conditioners that cannot be connected to an app

Can airCloud Go with air conditioners from another brand apart from Hitachi AC?

No, airCloud Go is exclusively for Hitachi air conditioners.

I don’t have wifi at home, can I connect my Hitachi air conditioner to airCloud Go app via 4G or Bluetooth?

As of today, connecting your Hitachi air conditioner can be done by wifi only. There is no connectivity by Bluetooth or 4G.

How long does FrostWash for outdoor unit take?

It takes approximately an hour to process.

Does FrostWash for outdoor unit self-cleaning cause noise disturbance?

Noise level of the FrostWash process for cleaning the outdoor unit’s coil is low (lower than regular AC operation).