Electric heater controller

Schematic

The thermal insulation of my apartment not being the best, I decided to buy an electric heater in order not to freeze during cold winter nights. However, the one I got was probably too powerful for my needs and letting it run for too long would heat up my place too much. Thus, I added a wifi enabled controller to it so its operations are controlled by my home automation system.

The controller consists of a relay connected to an ESP8266 which repsonds to MQTT commands. Moreover, a button is also added to allow for manual operations. The status of the heater is displayed using an LED. The firmware running on the ESP8266 is available on GitHub

The heater itself is pretty silent. However, the sound of an electromechanical relay might get annoying during the night so I chose to use an SSR-25DA solid state relay to turn the heater on and off.

Please note that handling mains electricity is extremely dangerous. Not only is there a high risk of electrocution, but also porrly designed devices can easily catch fire due to the high electric power involved. Attempt prjects like this one at your own risk.

The electronics are installed in a 3D printed enclosure attached to the back of the heater. Here is a list of the parts involved: