Firmware updates
You can find your units fw version number by looking at the splash screen when the unit starts up.

You can update firmware with any Windows PC. We currently don’t support firmware update using a Mac.

Drivers: Windows 10 will find and download the drivers for your Fridge Optimizer automatically. If you have Windows Vista, Windows 7 or Windows 8 (or 8.1) you can download the software drivers from this page: click here to download the CH340&CH341 drivers

Latest firmware version is Click here to download



  1. Download the software update .zip file. It will contain one .msi file and one .hex file
  2. Extract both files onto the desktop of your Windows PC.
  3. Open the update.msi file on your desktop
  4. Windows will complain that it’s downloaded from the Internet…
  5. Select “I understand the risk…” and click “Run anyway”
  6. Windows will now point out the file is from “An unknown publisher”.
  7. Click “Yes” to continue.


  1. Power off the fridge and disconnect the Fridge Optimizer Ethernet cable.
  2. Connect the Fridge Optimizer to the PC via a mini USB cable. The port is on the side of the unit.
  3. Let Windows locate and install the drivers for the new “Serial Connection”. *
  4. Open the Windows Start Menu and locate the “Fridge Optimizer Updater”.
  5. Select the “COM port” of the newly installed Fridge Controller.**
  6. Select the “Hex File” for on your desktop, that you just extracted, using the button with 3 dots.
  7. Press “Upload”.
  8. The application will say “Uploading…” followed shortly (20sec) by “… bytes uploaded”
  9. Done! Unplug the Fridge Optimizer from the PC. Plug the ethernet cable back in and power up the fridge again. Note the firmware version on the startup screen. Enjoy!

* See “Drivers” above if you run into issues.
** If you have several COM ports and the computer doesn’t detemine automatically which one is in use, just start from the top and try all of them until upload succeeds. If upload hangs for more than 30 s. Restart the Updater program and pick the next COM port.

Older firmware

Previous firmware version Click here to download

Legacy firmware version

  • Added settings UI, main screen UI and relay logic for voltage cut off feature (default value is set to 10.5V)
  • Added Cubigel (Cool Blue, Technautics) compressor support. “Cubigel” is a new option among the compressor alternatives. Note – you need a compatible connector block to run Cubigel, contact us for availability.
  • Freezer configuration option to disable thermostat fan (set defrost intervall to 999 to activate)
  • Changed the voltage divider top value from 33 to 31 Volts
  • Adjusted 24V mapping to be more exact
  • Adjusted ambient temp offset

Legacy firmware version

  • Ability to switch between compressor models
  • New ‘Demo Mode’ added for showing graphs and data without a connection to a compressor or sensors
  • Humidity history is now based on hour averages taken from readings every minute (instead of once an h)
  • Fixed an issue with humidity history graph scaling
  • Fixed the incorrect scaling of the temperature history graph.
  • Fixed color inconsistency in temperature history graph
  • Minor stability and UI changes


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