Dieselfire

DieselFire

⚠ ALPHA QUALITY — NOT TESTED ON HARDWARE

This project is in early development. The firmware has not been tested on physical ESP32-S3 hardware. All protocol simulation and UI development has been done via the PC simulator. There are likely bugs, edge cases, and incomplete drivers. Use at your own risk. Hardware bringup is in progress.

A modernized open-source controller for generic Chinese diesel heaters, forked from Afterburner by Ray Jones.

Overview

DieselFire is a complete redesign of the Afterburner project, updated with modern hardware while preserving the core functionality that made Afterburner popular:

• Diesel heater control via the "blue wire" half-duplex serial protocol (25000 baud)
• WiFi connectivity for web interface, MQTT, and OTA updates
• Bluetooth Low Energy for mobile app control
• Environmental monitoring with temperature, humidity, pressure, and CO detection
• Color touchscreen UI with LVGL graphics
• Programmable timers (14 channels)
• Fuel gauge and hour meter
• Smart error detection

Online Simulator

Try the DieselFire UI in your browser without any hardware: dieselfire.wabo.cc

Runs as a WebAssembly build of the native PC simulator. Includes the full touchscreen interface, Blue Wire protocol simulation, and a diesel heater emulator for testing all states and fault conditions.

Hardware

License

DieselFire is released under the GNU General Public License v3.0.

This project is a fork of Afterburner by Ray Jones (Copyright 2018-2020). The original Afterburner code was used as the foundation and has been substantially modified and modernized. All original Afterburner code remains under GPLv3 as per the original license.

See LICENSE for the full license text.

Quick Start

1. Hardware: Order PCB from JLCPCB/PCBWay using Gerber files in gerber/
2. Firmware: Install PlatformIO, then run pio run to build
3. Flash: Connect via USB-C and run pio run --target upload
4. Configure: Connect to the AP "DieselFire" (password: thereisnospoon) or connect to existing WiFi

Project Structure

DieselFire/
├── boards/                  # PlatformIO board definitions
├── docs/
│   ├── design/              # Design documents and specifications
│   ├── firmware/            # Firmware documentation
│   └── hardware/            # Hardware documentation
├── gerber/                  # PCB fabrication files
├── kicad/
│   ├── schematic/           # KiCad schematic files
│   ├── pcb/                 # KiCad PCB layout files
│   ├── footprints/          # Custom KiCad footprints
│   └── libraries/           # KiCad symbol libraries
├── lib/                     # PlatformIO libraries (vendored)
├── src/
│   ├── cfg/                 # Configuration headers
│   ├── Display/             # LVGL display driver and screens
│   ├── Protocol/            # Blue wire protocol handling
│   ├── RTC/                 # Real-time clock and timers
│   ├── Utility/             # Utility classes (sensors, storage, etc.)
│   ├── WiFi/                # WiFi, web server, OTA
│   ├── Bluetooth/           # BLE implementation
│   └── OLED/                # Legacy OLED code (to be removed)
├── platformio.ini           # PlatformIO project configuration
├── README.md
└── LICENSE

Features

Heater Control

• Power on/off commands
• Temperature setpoint adjustment
• Fuel mixture tuning
• Pump priming
• Thermostat mode (cyclic, stop/start, linear)
• Frost protection mode
• Humidity-based control
• OEM controller co-existence mode

Connectivity

• WiFi: STA mode (connect to existing network) or AP mode (captive portal)
• BLE 5: Bluetooth Low Energy for mobile app control
• MQTT: Publish heater status and receive commands
• Web Server: HTTPS web interface with WebSocket JSON streaming
• OTA: Over-the-air firmware updates

Sensors

• BME280: Ambient temperature, humidity, pressure (altitude)
• MQ-7: Carbon monoxide detection (external module)
• DS18B20: External waterproof temperature probe (optional)
• SCD41: CO2 sensing (optional, not on default board)

User Interface

• 2.8" Color Touchscreen: 320×240 ILI9341 with capacitive touch
• LVGL Graphics: Hardware-accelerated UI with PSRAM buffer
• Menu System: Hierarchical menus for all settings
• Timer Chart: Visual overview of 14 programmable timers
• Status Display: Real-time heater status, sensor readings, alerts

Safety

• CO Detection: MQ-7 sensor with alarm LED
• Low Voltage Cutout: Auto-shutdown when battery voltage is too low
• Error Detection: Smart monitoring of heater state transitions
• Watchdog: Hardware and software watchdog for reliability

Pinout

ESP32-S3 GPIO Mapping

Expansion Headers

H1 (2×10): GPIO33, GPIO34, GPIO35, GPIO36, GPIO37, GPIO38, GPIO39, GPIO40, 3.3V, GND, GND H2 (2×10): GPIO41, GPIO42, GPIO43, GPIO44, GPIO45, GPIO46, GPIO47, GPIO48, 3.3V, GND, GND

Connectors

Building

Prerequisites

• PlatformIO (latest version)
• ESP32-S3 compatible board (DieselFire PCB)
• USB-C cable

Build Commands

# Install PlatformIO
pip install platformio

# Clone the repository
git clone https://github.com/wabolabs/DieselFire.git
cd DieselFire

# Build firmware
pio run

# Upload to board
pio run --target upload

# Monitor serial output
pio device monitor --baud 115200

Board Definition

The DieselFire board is defined in boards/dieselfire.json. To use it:

pio run -e dieselfire

Configuration

WiFi Setup

On first boot, the device creates an access point:

• SSID: DieselFire
• Password: thereisnospoon

Connect to this AP and open a browser to 192.168.4.1 to configure WiFi.

MQTT Setup

Configure MQTT settings in the web interface or via the debug console:

• Server address
• Port (1883 for MQTT, 8883 for MQTT over TLS)
• Client ID
• Username/Password (if required)
• Topic prefix

Sensor Calibration

MQ-7 CO Sensor:

1. Power on the device in clean air (outdoors)
2. Wait 48-72 hours for the sensor to stabilize
3. Use the web interface to run calibration
4. The R0 value is stored in non-volatile memory

DS18B20 Temperature Probe:

1. Connect the probe to J4
2. The probe will be auto-detected on boot
3. Set offset in settings if needed

Hardware Design

PCB Specifications

• Size: 80mm × 60mm
• Layers: 2-layer
• Trace width: 0.2mm signal, 0.5mm power, 1mm 12V
• Via size: 0.3mm hole / 0.6mm pad
• Clearance: 0.15mm minimum

BOM

PCB fabrication: ~$5-10 for 5 boards (JLCPCB/PCBWay, 2-layer, 80×60mm)

Firmware Development

Architecture

The firmware follows a modular architecture:

┌─────────────────────────────────────────────────────────────┐
│                     DieselFire                                │
│                                                              │
│  ┌─────────────┐  ┌──────────────┐  ┌──────────────────┐   │
│  │  Display    │  │   UI Layer   │  │  Settings/Config │   │
│  │  (LVGL)     │  │  (Screens)   │  │  (NVS Storage)   │   │
│  └─────────────┘  └──────────────┘  └──────────────────┘   │
│                                                              │
│  ┌─────────────┐  ┌──────────────┐  ┌──────────────────┐   │
│  │  Protocol   │  │  Blue Wire   │  │  Sensor Layer    │   │
│  │  Handling   │  │  State Machine│ │  (BME280, MQ-7)  │   │
│  └─────────────┘  └──────────────┘  └──────────────────┘   │
│                                                              │
│  ┌─────────────┐  ┌──────────────┐  ┌──────────────────┐   │
│  │  WiFi/HTTP  │  │  BLE/Bluetooth│ │  MQTT/OTA        │   │
│  └─────────────┘  └──────────────┘  └──────────────────┘   │
│                                                              │
│  ┌──────────────────────────────────────────────────────┐   │
│  │                    ESP32-S3 Hardware                  │   │
│  └──────────────────────────────────────────────────────┘   │
└─────────────────────────────────────────────────────────────┘

Key Modules

Development Workflow

1. Create a feature branch

   git checkout -b feature/new-screen

2. Make changes

   • Add/modify code in src/
   • Update documentation in docs/

3. Build and test

   pio run
   pio run --target upload
   pio device monitor --baud 115200

4. Commit and push

   git add .
   git commit -m "Add new screen for timer overview"
   git push origin feature/new-screen

5. Create a pull request

Troubleshooting

Board Won't Flash

• Check USB-C cable (must be data-capable, not charge-only)
• Hold BOOT button while pressing RESET
• Check COM port in platformio.ini

Display Not Working

• Verify FPC connector is seated correctly
• Check SPI pin connections
• Verify PSRAM is detected (check serial output)

BME280 Not Detected

• Check I2C address (0x76 or 0x77)
• Verify pull-up resistors (4.7kΩ on SDA/SCL)
• Run I2C scanner from debug console

MQ-7 Readings Unstable

• Ensure 48-72 hour warmup period
• Run calibration in clean air
• Check voltage divider (10kΩ + 10kΩ)
• Verify ADC pin (IO4) is correct

Blue Wire Communication Issues

• Verify level shifter connections (BSS138)
• Check Tx gate control (IO47)
• Verify UART0 pins (IO43/IO44)
• Check heater blue wire is connected correctly

Contributing

Contributions are welcome! Please:

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

Please ensure your code follows the existing style and includes appropriate documentation.

Acknowledgments

DieselFire is a fork of Afterburner by Ray Jones. The original Afterburner project was a groundbreaking open-source controller for Chinese diesel heaters, and this project builds upon that foundation.

Special thanks to:

• Ray Jones (Afterburner original author)
• James Clark (Afterburner co-author)
• The Afterburner community on GitLab
• The ESP32 and LVGL communities

Disclaimer

DieselFire is provided "as is" without warranty of any kind. The authors are not responsible for any damage caused by the use of this software or hardware. Diesel heaters produce carbon monoxide and other hazardous gases. Always ensure proper ventilation and installation.

Use at your own risk.