The purpose of this Instructable is to show how works my Hot water pump recirculating control system.
I use a solar thermal plate, that save the hot water in a thermal tank, and I have installed at home a system that allow us enjoy of hot water once you open the pipe, without waste cold water waiting for the hot water, saving many liters of water.
The problem is that if I allow the pump to work continuosly, it cold the water stored in the tank. So, I have desing a little system with Arduino that allow us control automatically the pump in relationship with temperature and also with remote control for custom activation of pump. Also, I can also control the internal resistence of thermal tank to heat water in cloudy days in winter.
Moreover, current status of system is monitorizing by wifi with help of an ESP8266 module.”