Control a hot water circulation pump.
The hot water circulation pump used to work all the time. To save some energy at home it was necessary to control the pump cycles. The ESP8266 is an ideal platform to realize this kind of project. One of the IO ports is connected to a temperature sensor and another port is connected to a solid state relay. The control software offers an web interface to enter the temperature set points and the pump operation time/day. This version of the software offers 4 timers.
After setting the timers and temperature set points the pump is running during ON time. That means it runs only when the hot water is needed immediately. If hot water is needed during off time the interface allows to switch the pump on or off manually.”