Control of Harvia 8kW 3-phase cooker with Home Assistant - relay selection and integration

I would like to connect a sauna heater (Harvia 8 kW, three-phase) with Home Assistant or another Smart Home system. While I will take care of the Home Assistant itself, I don't quite know how to talk to an electrician about the installation. What is the easiest and safest electrical device to control the sauna cooker? How do I solve the communication of the appliance with the Home Assistant? The sauna is in a holiday home and can be run several times a day, depending on occupancy.

Depends on the cooker. If it starts as soon as power is applied, a contactor will suffice.

>>21725498 At the moment, the sauna is controlled by such a simple panel. The temperature is set permanently with a knob; all that needs to be done is to switch the button responsible for heating from 0 to 1. I understand that with a contactor, I would leave the heating button on the panel in the on position and place a contactor in front of it to manage whether power is reaching the panel. Any specific examples of contactor models that will handle the appropriate power and that will be easy to integrate with Home Assistant or other Smart Home systems?

richbox wrote:

I understand that with a contactor I would leave the heater button on the panel permanently activated and put a contactor in front of it

And why so ? Check that the button does not just switch on the contactor or SSR of the heaters and put a relay there.