# QuietCool ESPHome: reconstructing IT-AF-SMT BLE control

> QuietCool ESPHome replaces firmware on the IT-AF-SMT attic-fan controller and reimplements its stock BLE interface so the vendor app can still control the hub. Its protocol reference draws on analysis of the OEM firmware, Android app, and live BLE captures, while the new firmware adds Wi-Fi and Home Assistant control.

- Type: Case study
- Targets: Firmware · Protocol
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-08
- Added to the catalog: 2026-11-08
- Original resource: <https://github.com/CrazyCoder/quietcool-esphome-native>
- Primary source: <https://github.com/CrazyCoder/quietcool-esphome-native/blob/01cdda32003022b47b4bd7d65cb057ea0ed37417/docs/OEM-BLE-PROTOCOL.md>
- Catalog page: <https://awesomerea.org/resources/quietcool-esphome-native-case/>
- Record JSON: <https://awesomerea.org/resources/quietcool-esphome-native-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/quietcool-esphome-native-case/index.md)

## Requirements & limits

- **Prerequisites:** A QuietCool IT-AF-SMT Smart Attic Fan Control hub.
- **Limits:** Historical analytics charts and AirControl Venting Assist are unimplemented; the browser installer does not support iOS or iPadOS.
- **License:** GPL-3.0 License.

## Primary sources

1. <https://github.com/CrazyCoder/quietcool-esphome-native/blob/01cdda32003022b47b4bd7d65cb057ea0ed37417/docs/OEM-BLE-PROTOCOL.md>
2. <https://github.com/CrazyCoder/quietcool-esphome-native/blob/01cdda32003022b47b4bd7d65cb057ea0ed37417/README.md>
3. <https://github.com/CrazyCoder/quietcool-esphome-native/blob/01cdda32003022b47b4bd7d65cb057ea0ed37417/LICENSE>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.