Microcontroller
STMicroelectronics STM32 NUCLEO-L476RG

Controls all the peripherals.

Datasheet
Temperature Sensor
Adafruit High Temp Waterproof DS18B20 Digital Temperature Sensor
Protocol: 1-Wire through half duplex UART

Checks the water temperature.

Datasheet
Display
SunFounder I2C LCD2004
Protocol: I2C

Displays status.

Specifications
Bluetooth
HiLetGo AT-09 Bluetooth Transceiver (HM-10)
Protocol: UART

Sends and receives messages.

Datasheet
Water Heater
API 742G 120V Bucket Heater

Heats up the water.

Instructions
Water Pump
Bringsmart JT-660D 12V DC Water Pump

Circulates the water.

Specifications
Relay
Digital Loggers IoT Relay

Supplies power to water heater and pump.

Specifications