Hot Tub Thermostat

See: MikkoTervala/hot-tub-thermostat

Digital temperature controller for an outdoor hot tub with wireless bluetooth temperature sensor.

Specifications

• ESP-32 microcontroller
• LCD display
• Waterproof buttons for outdoor installation
• Wireless Bluetooth LE temperature sensor
  • Inkbird IBS-TH1 with external temperature sensor
• Software written using esphome
  • A new feature was implemented to esphome for the temperature sensor. See: https://github.com/esphome/esphome/pull/1983

Functionality

The system acts as a thermostat controlling temperature of an outdoor hot tub. The hot tub is heated with a natural gas instant lake water heater. As temperature goes down, the thermostat will let more hot water in. The thermostat will be installed near the water heater, so a wireless temperature sensor is used to avoid wires.