Design of Automatic Exhaust Control System of Central Heating System Based on S7-200 SMART PLC

In the central heating system, air accumulation in the heating pipe caused by hydraulic and thermal imbalance and other faults. In this paper, Siemens S7-200 smart PLC is adopted as the core to design the automatic exhaust device, including water, vacuum, drainage automatic control system. The air accumulated will be discharged timely and effective with touch screen interface, PLC control program and monitoring system combined to implement the control mode. Through the using automatic exhaust device and equipped with automatic control system to discharge dissolved gas in water, improving the stability of heat network equipment operation and achieving ideal heating effect.