HeatIt thermostat – firmware update cable

wojofibaro · January 23

Hi everyone,

I have a few HeatIt TF021 Z-Wave thermostats at home and I’d like to do a firmware update.

Does anyone here have a schematic of the cable needed for the firmware update? Or maybe you have the cable for sale or rent?

Thanks in advance for any help! 😊

awlieser · January 23

You don‘t a cable - those are OTA updates

wojofibaro · January 23

OK. Can You help with that? Where to find this option under FHC3?

wojofibaro · January 26

W dniu 23.01.2026 o 11:38, awlieser napisał:

You don‘t a cable - those are OTA updates

Below is the response from Heatit support — as you can see, the update can only be done using the special cable:

“The Z-Wave (TF021) only has updates which can only be done via a special cable.”

I’m repeating my request: does anyone have the cable schematic they could share?

awlieser · January 26

Sorry, I was wrong here - I thought you were referring to the Fibaro thermostat.

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