Steam Bath Controller Programming

I need a compact control circuit for a steam-bath machine and I want it fully programmed and ready to drop into the enclosure. The heart of the job is reliable temperature management: the board must read a temperature sensor, compare it to set-points, and drive the heater and solenoid valves accordingly while keeping everything within safe limits.

I’m flexible on the platform—Arduino, Raspberry Pi, PIC, or any MCU you feel best matches the load and environmental constraints—so long as replacement parts remain easy to source. If your choice supports future add-ons such as humidity or pressure sensing, all the better.

Deliverables
• Circuit schematic and PCB layout (Gerber files)
• Firmware with clear, commented source code
• Bill of materials with part numbers available worldwide
• Simple front-panel wiring diagram and user-level documentation
• Short test protocol showing the temperature sensor triggering heat on/off cycles correctly over at least three set-points

Code should compile without warnings, and the finished board should tolerate the high-humidity environment typical of steam cabinets. If you’ve built spa, sauna, or HVAC controllers before, I’d love to see a quick reference to that experience in your bid.