Sauna Lights RF Controller

ESPHome-based 433MHz RF transmitter for controlling sauna LED lights via Home Assistant.

Overview

This project uses an ESP32-S3-DevKitC-1 development board with a 433MHz RF transmitter module to control LED light strips in a sauna. The device integrates with Home Assistant, exposing 44 button commands as services for complete remote control.

Hardware

• Board: ESP32-S3-DevKitC-1 (ESP32-S3-WROOM-1)
• RF Module: 433MHz transmitter on GPIO4
• Power: USB or 5V pin
• Status LED: Onboard RGB LED (GPIO38)

Wiring

Component	GPIO	Notes
RF Transmitter TX	4	433MHz, VCC=5V (recommended)
Status RGB LED	38	Onboard LED (v1.1 board)

Features

• Custom PT2262 component with proper tri-state encoding
• All 44 button commands for complete sauna light control
• Home Assistant integration via ESPHome API
• OTA updates for easy maintenance
• WiFi connectivity with fallback AP mode
• Diagnostic sensors (WiFi signal, uptime, temperature)
• Web server for debugging
• RTL_433 compatible signal generation

Installation

Prerequisites

• ESPHome installed (pip install esphome)
• USB cable for initial flashing
• 433MHz RF transmitter module
• WiFi network credentials

Setup

1. Configure secrets:

   cp secrets.yaml.example secrets.yaml
   # Edit secrets.yaml with your WiFi credentials and API keys

2. Configure device (if needed):

   cp consts.yaml.example consts.yaml
   # Edit consts.yaml with device-specific settings

3. Validate configuration:

   make validate

4. Build firmware:

   make build

5. Flash via USB (first time only):

   make flash

6. Add to Home Assistant:

   • Go to Settings → Devices & Services
   • Add ESPHome integration
   • Device should auto-discover as "sauna-lights-356f"

Usage

Home Assistant Services

After adding to Home Assistant, 44 services will be available:

• esphome.sauna_lights_356f_brightness_up - Increase brightness
• esphome.sauna_lights_356f_brightness_down - Decrease brightness
• esphome.sauna_lights_356f_red - Set color to red
• esphome.sauna_lights_356f_diy1 - Activate DIY preset 1
• ...and 40 more button commands

See docs/HA-ENTITIES.md for complete service documentation and Home Assistant entity reference.

Development Workflow

# Validate configuration
make validate

# Build firmware
make build

# Flash via USB (first time)
make flash

# Update via OTA (after first flash)
make ota

# View logs
make logs

# Generate entity list for dashboard
make dashboard

# Start ESPHome dashboard
make esphome-ui

# Clean build artifacts
make clean

Documentation

Component Documentation

• PT2262 Component - Custom component technical details
• PT2262 Implementation Guide - Implementation notes and troubleshooting

Home Assistant Integration

• HA Entity Reference - Complete list of all entities, services, and dashboard examples
• Button Mapping - Complete 44-button tri-state code reference

Hardware & Testing

• ESP32-S3 Details - Board specifications and GPIO reference
• Power Analysis - RF transmitter power optimization (3.3V vs 5V)
• Signal Captures - Original remote RTL_433 captures

Project Status

• Documentation Status - Documentation accuracy and testing status

Technical Details

PT2262 Protocol

This project uses a custom ESPHome component to properly implement the PT2262/PT2272 remote control protocol. Key features:

• Tri-state encoding: Directly uses 4-state symbols (0, 1, X, Z)
• Pulse pair structure: Each symbol encoded as TWO pulses (not flat binary)
• Verified timing: 432µs/1232µs pulses, 392µs/1192µs gaps, 12020µs sync
• RTL_433 compatible: Signals decode as "Generic-Remote" with proper tri-state display

Why a custom component?

ESPHome's built-in remote_transmitter doesn't properly implement PT2262 tri-state encoding:

• Sends flat binary sequences instead of pulse pairs
• LED receivers don't recognize the signal structure
• RTL_433 decodes as generic PWM, not Generic-Remote

The custom component solves this by implementing the exact pulse pair encoding that PT2262 receivers expect.

Verified Implementation

PT2262 Component Testing (RTL-SDR verified):

• ✅ Brightness Up/Down
• ✅ DIY1/DIY2
• ✅ Red/Green/Blue/White
• ✅ Power

All buttons use identical PT2262 component implementation with verified tri-state encoding. The remaining 37 buttons follow the same pattern and signal structure.

Troubleshooting

Device won't connect to WiFi

• Verify credentials in secrets.yaml
• Ensure 2.4GHz network (ESP32 doesn't support 5GHz)
• Check serial logs: make logs
• Try fallback AP: connect to "sauna-lights-356f Fallback" hotspot

RF signals not working

• Verify GPIO4 connection to transmitter module
• Check transmitter power (3.3V, not 5V)
• Add antenna (17.3cm wire for 433MHz)
• Increase RF signal repeat count in configuration

OTA updates failing

• Ensure device is on same network
• Check OTA password in secrets.yaml
• Try flashing via USB and retry OTA

Contributing

Contributions welcome! Please:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Submit a pull request

Author

Robert Sigler (code@sigler.io)

License

MIT License - see LICENSE file for details