The article presents the results of the synthesis of digital controllers for automatic control systems of heat exchangers of central air conditioning systems, functioning under variable significant disturbing influences. The developed regulators are designed to provide the specified quality of regulation (short regulation time, permissible value of regulation), changes in the settings of the regulators taking into account the operating conditions of the regulatory object. The circuitry of regulators should be relatively simple. The requirements for the developed controllers are implemented in a typical digital PID-controller with optimization of its settings using the differential evolution algorithm. To assess the quality of PID-regulation, the regulator was tested in the ModelSim program. Test results were analyzed using Matlab. In order to implement the requirements for the developed regulators as an alternative to the PID-regulator with optimization of its settings using the differential evolution algorithm, a combined automatic control system based on the P-regulator has been created. The control system contains a P-controller with a synthesized corrective link, providing control by the deviation of the controlled variable from its predetermined value and by the perturbation applied to the controlled variable. Assessment of the quality of regulation of the P-regulator with the corrective link was carried out according to the results of research at Matlab. PID-controller with optimization of its settings using the differential evolution algorithm, as well as P-controller with corrective link is implemented in FPGA. The main language for describing the hardware for implementing regulators in FPGAs is the language for high-speed integrated circuits (VHDL). A comparative analysis of the results of a study of a digital PID-controller with parameter optimization and a combined automatic control system made it possible to establish that the controllers satisfy the required regulatory quality in the automation of heat exchangers in central air conditioning systems that are subject to significant disturbances. They have the ability to change settings taking into account the operating conditions of the regulatory object. It was found that the use of a P-controller with a synthesized corrective link, which has a simpler circuit solution, allows us to provide better control quality indicators in comparison with a PID-controller with optimized settings.