The meter by dranek is a separate external device for additional measurements. It is not required for basic Samovar operation and is not part of the Samovar firmware: Samovar does not read its values.
The meter source code is in the Samovar repository, in the pro_mini_ntc directory (an ESP8266 sketch, a "Схема и плата" ("Schematic and board") folder with the circuit diagram and Gerber files, and a "Справочная информация" ("Reference information") folder with a description). This directory is not included in the Samovar firmware build.
