Active heater controller

The original controller of my heater is too buggy:

• loses state after a power loss;
• target temperature must be a round number;
• its thermocouple is not precise enough. So an Arduino based controller is about to replace it.

Target features:

• support all three speeds of the fan;
• measure room temperature;
• measure heating water temperature;
• stop the fan if heating water is colder than target temperature;
• display data on a segmented LCD;
• settable target temperature via buttons;
• programmable schedule.

Hardware used

Currently it works with a TMP36 sensor which should be replaced with a DHT22 for better accuracy and wider measuring bandwidth. The LCD used will be a 16x2 with an I2C controller. In a future version the controller should be split in two parts - one that controls the heater and a remote one with display, buttons and temperature sensor.