Components

ESP32Kiln is a combination of hardware components, that you need to acquire and software that you can download from Github.

It should be quite easy to build and in my opinion does not involve much technical skill. Before starting, you should know what voltage and current is, have some basic understanding of Arduino IDE, and be comfortable working near mains voltage. Some soldering skills could also be useful (but you can build it completely on a breadboard, without soldering).

You also don't have to build everything at once. There are optional parts and you can start with a minimal set of components and upgrade later.

Components list

Required components:

• ESP32-Wrover or ESP32-Wroom board (Wrover recommended)
• MAX31855 breakout board
• K-type thermocouple
• DC->AC solid state relay

Optional, but highly recommended:

• 128x64 dot matrix LCD 12864B v2
• Rotary encoder with button

Optional:

• DC/AC secondary relay - like SLA-05VDC-SL-C (240V/30A) mechanical relay
• Additional MAX31855 board with K-type thermocouple for housing temperature measuring
• Coil power meter - 30A/1V. This is a contactless power meter that generates a small current when energy flows inside its coil. Mine already had a burden resistor - so on output it produces -1V to 1V, proportionally rated for 30A. We just need to measure it to know how much power flows to the heater.
• Perhaps a kiln :)

Bill of materials

Total expenses for this set should be around 30-40$ (depending on where you buy it)

• ESP32-Wrover board: 11-14$ if exactly like mine, but other ESP32-Wrover you can buy for 6$+
• MAX31855 board: ~2$
• K-type thermocouple: 1$-10$ - depending on max temperature it can withstand
• 2x 10-100nF capacitors (for thermocouple noise filtering, one per MAX31855)
• LCD 12864B: ~5$
• Encoder: 1$
• SSR: 4$ + 4$ for heat sink
• Mechanical relay EMR SLA-05VDC-SL-C (Songle): 3$