The main goal of this paper is to present the automation of the older heat treatment furnace with the improved regulation of process parameters. In the introduction, it is explained why heat treatment processes are used in the production process of tools and parts. In the first part of the paper, brief descriptions of several heat treatments such as annealing, tempering and tempering are given, as well as a brief description of heating devices with a more detailed description of chamber furnaces. After that, PID regulation is described, the basics and principles of PLC operation are given, and the basics of the LOGO! Soft Comfort software package are given. In the second part of the paper, a list of requests for furnace automation is presented, the equipment used to perform the said automation is presented. In the last chapter, the developed PLC program for managing heat treatment procedures is presented, and the conclusions are presented.