| Item | Value |
|---|---|
| Model | Core 300S |
| Tested MCU FW | 2.0.7, 2.0.11 |
| ESP Module | ESP32-SOLO-1C |
| Board | CORE300S Ctrl Board V1.4.1 |
| Fan Speeds | 3 |
| CADR (spec) | 214 m³/h |
| Room Size | 9–50 m² (97–538 ft²) |
| ESPHome | 2026.1.2+ |
| PM Sensor | PM2008MS |
| Feature | Type | Notes |
|---|---|---|
| Fan | fan | 3 speeds, presets: Manual / Auto / Sleep |
| Auto Mode | select | Default / Quiet / Room Size |
| Auto Mode Room Size | number | 9–50 m² |
| Display | switch | Toggle LED display |
| Child Lock | switch | |
| PM2.5 | sensor | µg/m³ |
| AQI | sensor | As reported by MCU |
| Current CADR | sensor | m³/h, updated every 5s |
| Filter Life Left | sensor | % remaining |
| Filter Low | binary_sensor | On when < 5% |
| Filter Lifetime | number | Configurable in months |
| Reset Filter Stats | button | Resets CADR/runtime counters |
| Timer | number | Run timer in minutes |
| MCU Version | text_sensor | |
| Error | text_sensor | "Ok" or "Sensor Error" |
- Place upside down, remove base cover and filter to expose 8 screws (4 have washers)
- Remove all 8 screws — they are soft metal, do not overtighten when reassembling
- Slide a pry tool between the tabs to separate base and top sleeve
- Unplug the logic board
Solder wires to TXD0, RXD0, IO0, +3V3, GND near the ESP32 on the logic board and connect to a USB-UART converter. On some boards these are through-holes and soldering may not be needed.
Connect IO0 to GND before powering on to enter bootloader mode.
For flashing you only need to solder to the pin header, the black and white are connected to dump esp to mcu communication
esptool read_flash 0 ALL levoit-core300s-backup.binNote: backup may fail on some boards — proceed at your own risk.
- Copy
secrets-example.yaml→secrets.yamland fill in your Wi-Fi and encryption key - Adjust the device name in the config if running multiple units
- Check the component README for UART pin mapping per board
esphome run levoit-core300s.yamlReassemble and enjoy!
Use the pre-generated builder yaml to flash without a local clone — all config is inlined, no !include or packages needed:
| File | Board |
|---|---|
levoit-core300s-builder.yaml |
original ESP32-SOLO-1C |
levoit-core300s-builder-c3.yaml |
ESP32-C3 replacement |
levoit-core300s-builder-s3.yaml |
ESP32-S3 replacement |
Upload to the ESPHome web builder or paste into the ESPHome dashboard. Regenerate with .\make-builder-yaml.ps1 from the devices/ folder.
esptool erase_flash
esptool write_flash 0x00 levoit-core300s-backup.binReplacing the original ESP32 allows switching back to original firmware without re-flashing and makes future updates easier.
Recommended modules (compact and reliable):
- Seeed XIAO ESP32-C3
- Seeed XIAO ESP32-S3 (overkill but works)
Wiring: 4 wires — +3.3V, GND, RX, TX
The RX/TX pads are not on the pin header — use the test pads near the original ESP32 on the board. Pull the
ENpin of the original ESP32 to GND to disable it.
Placement of new ESP
The small xiao seeeds fit into the small existing space, make sure to isolate and solder the connections.
I connected to 5V, cause i had issues on the 3.3v with my xioa seeed s3. It rebooted with brownout (power issues). I think my en to gnd connection might not have been stable but still decided to use 5V.
