The anti-freeze system for heat pumps is a complete set for emergency forcing of water circulation in a monoblock heat pump system. It makes it possible to protect the water in the heat pump from freezing in the event of a power outage, immobilization (e.g., caused by a flow error) and tripping of current protection. The controller, built into the system, automatically starts the included, built-in pump. When the temperature in the system drops below 15℃, the pump works according to the designed algorithm, shortening the intervals between each cycle - forcing water to circulate through the PC. To ensure trouble-free operation of the system, at all times after its installation, the pump is automatically started, which minimizes distortion in temperature readings and further prevents the pump from stagnating.