Trimatik MC is an older heating control from Viessmann. It has no supported digital interface for remote access, but I found at least two ways to get access to sensor data like various temperatures and state of relay contacts. One way is to use the so called remote control the other use the clock timer. This project will use the latter way, because the hardware adaption is much easier and and all four timer channels could be controlled as well. Remote access will be done via an ESP32, which emulates the clock timer and gets/pushes data via WIFI.

Current prototype is able is able to monitor traffic between the original clock timer and the heating control.

Next steps:

• implement remote updates of the ESP firmware.
• finish hardware wiring to get the ESP between clock timer and heating control
• emulate clock timer
• present sensor data some way
• get configuration data for timer channels