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Troubleshooting

Answers to common questions and problems. If your issue is not covered here, contact us and we will help.

The device does not appear when I try to provision over Bluetooth

The CTRL ONE only advertises itself over Bluetooth while it is unprovisioned - once it has joined a WiFi network it stops advertising. If you have set it up before, or provisioning was interrupted, reset it first, then try again:

  1. Power-cycle the device five times in quick succession (within about 10 seconds) to factory reset it. This returns it to the unprovisioned state.
  2. Make sure the device is powered - either over USB or through the add-on slot.
  3. Move the device closer to your computer or phone; Bluetooth has a limited range.
  4. Use Home Assistant for Bluetooth provisioning, or try the ESPHome Device Builder.
  5. If Bluetooth still fails, provision over the USB serial connection instead (see below).

The device is not detected when I try to provision over serial (USB)

  1. Make sure you are using a data-capable USB-C cable. Many cables are charge-only and will not carry a serial connection.
  2. Use Chrome or Edge, which support the browser serial connection used by ESPHome Web.
  3. Try a different USB port or a different cable.
  4. Confirm the device powers on when plugged in (the screen should wake or the indicator light should pulse).
  5. If serial still does not work, provision over Bluetooth instead (see above).

The device will not connect to my WiFi network

The CTRL ONE connects to 2.4 GHz WiFi only - it cannot see 5 GHz networks. If your router uses a single combined network name (SSID) for both bands, or uses band steering, the device may fail to connect. Try the following:

  1. Check that the 2.4 GHz band is enabled on your router.
  2. If your router uses band steering or a combined SSID, temporarily disable band steering, or create a separate 2.4 GHz network name.
  3. Reprovision the device with the 2.4 GHz network credentials.

I press a button on the display but nothing happens in Home Assistant

Home Assistant has a per-device security setting that controls whether an ESPHome device may trigger Home Assistant actions. It is disabled by default, so a device can report its state but cannot turn things on, change values, or run automations until you allow it:

  1. In Home Assistant, open Settings > Devices & Services.
  2. Open the ESPHome integration and select your CTRL ONE.
  3. Enable the option Allow the device to perform Home Assistant actions.
  4. Try the button again - it should now control the linked entity.

The device does not show up in Home Assistant after connecting to WiFi

  1. Confirm the device is on the same network as your Home Assistant server (discovery relies on local multicast).
  2. Wait a minute or two for discovery to complete.
  3. Restart the device using the Restart button in the Device Builder, or by power-cycling it.
  4. If it still does not appear, the WiFi connection may not have succeeded - check the previous question.

The display is blank or not updating

The ePaper display refreshes on an interval and on interaction, so a static screen is normal. If it is completely blank:

  1. Tap the screen to wake the backlight and trigger a refresh.
  2. Power-cycle the device and confirm the welcome screen appears.
  3. If a recent configuration change caused the problem, use the Restart (Safe Mode) button and re-flash a known-good configuration.

The display does not show changes from Home Assistant immediately

To avoid the ePaper display flashing and refreshing too often when it is not in use, the display updates once every 30 seconds. When you touch the screen, the refresh rate increases so it responds immediately, and it returns to the slower interval after a short period of inactivity.

The device takes a few minutes before it shows sensor data

After power-on, the CTRL ONE waits for its sensors to stabilise before showing readings. This takes about five minutes, during which the display shows a waiting message rather than values. This is normal - the SCD40 sensor needs this time to settle and produce accurate readings. Once the readings are stable, the display begins showing temperature, humidity and CO2 automatically.

The device will not power on

  1. Check the power source: 5 V over USB-C, or power through the add-on slot.
  2. If the device is wall-mounted, the USB port is not accessible - power must come through the add-on slot (the 24VAC add-on or the breakout add-on).
  3. Try a different USB power supply and cable.

I need to reset the device or I forgot the WiFi network credentials

Power-cycle the device five times in quick succession (within about 10 seconds). This factory resets the device, returning it to the unprovisioned state so you can set it up again from scratch.

This depends on how the ESPHome firmware is customised. If you've placed the WiFi credentials in the ESPHome configuration itself, then they will survive a factory reset. You'll need to connect it to a computer over USB and flash a new firmware with the new credentials.

An over-the-air update failed and the device is unresponsive

  1. In Home Assistant, press the Restart (Safe Mode) button. Safe mode boots a minimal configuration so the device can be reached again.
  2. Re-flash a known-good configuration from the Device Builder or Home Assistant.
  3. If the device cannot be reached at all, connect it over USB and re-flash it directly.

The status LED cycles through different colours when I first start the device

This indicates that the testing firmware used during the manufacturing process has been left on the device. This has not happened with any order, but it has the possibility to happen, so it's listed here. The test firmware includes some debug widgets to ensure all functionality is working, and it flashes the notification LED in sequence to check all colors. Rest assured, the device is tested and working - you'll just need to flash the standard firmware to it in the same way you'd update the firmware.

  1. Connect the CTRL ONE to your computer with a USB-C cable.
  2. Open the ESPHome Device Builder (the installed app) and adopt the device.
  3. Flash the standard CTRL ONE firmware to it.
  4. Once flashed, the status LED will behave normally.