TECH ST-480 / ST-500 — Home Assistant Integration

Custom integration for Home Assistant to monitor TECH ST-480 and ST-500 boiler controllers via the built-in web module.

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Features

• Real-time monitoring of boiler state, temperatures, pumps, fans and valves
• Automatic sensor discovery based on register definitions
• Last-known-good value retention when a register is temporarily unavailable
• Configurable polling interval
• Outdoor temperature calibration offset
• Dynamic entity icons based on boiler state

Supported devices

Device	Status
TECH ST-480	✅ Tested
TECH ST-500 (web module)	✅ Tested

Requirements

• Home Assistant 2023.6 or newer
• TECH ST-480 / ST-500 controller with the ST-500 web module connected to your local network
• HTTP access to the web module (default port 80)

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Installation

Via HACS (recommended)

1. Open HACS in Home Assistant
2. Go to Integrations → three-dot menu → Custom repositories
3. Add https://github.com/Martin-Humr707/tech_st500 as an Integration
4. Find TECH ST-480 / ST-500 and click Download
5. Restart Home Assistant

Manual

1. Copy the custom_components/st480 folder to your HA config/custom_components/ directory
2. Restart Home Assistant

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Configuration

1. Go to Settings → Devices & Services → Add integration
2. Search for TECH ST-480
3. Fill in:
   • Host — IP address of the ST-500 web module (e.g. 192.168.1.100)
   • Username — HTTP Basic Auth username (default: user)
   • Password — HTTP Basic Auth password
   • Scan interval — polling interval in seconds (default: 5)
   • Outdoor temperature offset — calibration offset in °C (default: 0.0)

Reconfiguration

After setup you can adjust the scan interval and outdoor temperature offset anytime via: Settings → Devices & Services → TECH ST-480 → Configure

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Sensors

Sensor	Unit	Notes
Boiler state	—	Text description + raw code attribute
Boiler outlet temperature	°C
Boiler setpoint temperature	°C
DHW temperature	°C
DHW setpoint	°C
Outdoor temperature	°C	Offset calibration supported
Flue gas temperature	°C	Optional sensor
Feeder temperature	°C
Fan speed	%
Fuel level	%
Remaining heating time	d
Feeder / Fan / Pump running	—	Binary status
Valve opening / setpoint / temperature	% / °C
And more…

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License

This project is licensed under the MIT License.

Disclaimer

This integration is not affiliated with or endorsed by TECH Controllers. Use at your own risk.