Home automation connectable hysteresis thermostat (ESP based)

thingiverse

The idea behind this thing is to make a home automation connected thermostat, based on a nodeMCU, ESPEasy rules, and a Nextion screen. The thermostat can be 'remote controlled' and thus acts as a simple relay. But it has also an stand-alone mode, working with an adjustable hysteresis. When controlled by home automation, there are two adjustable safety temperatures beyond which the thermostat reverts to stand-alone mode (and last user setpoint). It is originally made to work with Jeedom, but any home automation controller able to post urls will work. The making of this is reserved to people who are comfortable with electronics and "precision" welding. Scope of work / features : - Adjustable setpoint, accuracy is 0.1°C - Tactile screen - Embedded temperature sensor (dallas 18b20) - Hysteresis mode - Adjustable hysteresis - Setpoint is remotely adjustable - On/Off button to enable / disable the thermostat - 'Remote' mode where the home automation triggers heating (called 'bypass' in my tutorial) - Adjustable safety temperatures to let the thermostat disable home automation by itself if necessary - In case of safety triggering, the last manual setpoint is used - The thermostat can display and report various values to the controller : actual temperature, setpoint, humidity (if available), heating On/Off, remote mode On/Off, global On/Off status - Full url control through ESPEasy rules specific 'functions' - Increased security in rules to avoid heating permanently On. - The device saves / restores its parameters in case of power shutdown - Home automation controller is warned in case of device reboot - Capacitive switch to sleep / unsleep the screen - Remote mode can be disabled from the thermostat - Power supply can be 230V or 5V (micro usb) - The relay is potential free, with NO/NC outputs - 3D printable enclosure You will find a complete tutorial here : https://community.jeedom.com/t/tuto-thermostat-tactile-simple-connecte/10843 (in french, sorry ; but Google translate gives quite good results on the Jeedom Forum, and there are many pictures to help) The device has been tested for 3 months in my home, in parallel with a 'standard' thermostat, external thermometer, and behaves as expected...