Troubleshooting

Troubleshooting ES1

This page covers common issues when setting up or using your Airlytix ES1 and how to fix them.

If you are just getting started, you may also want to review:

Power and hardware

ES1 does not power on

  • Use a known‑good USB‑C cable and power supply (at least 5 V / 1 A).
  • Check that the USB‑C connector is fully seated in the ES1.
  • Look for any sign of life when plugged in (status LED, indicator light flash).

If there is no sign of power with multiple cables and supplies, the device may be faulty and you should contact support.

WiFi setup problems

I cannot see the ES1 WiFi hotspot

  • Make sure ES1 is powered from a reliable USB power supply.
  • Wait at least 30–60 seconds after plugging it in.
  • Look for a network named airlytix-es1-xxxxxx in your device’s WiFi list.
  • Move closer to the device and refresh the WiFi list.

If the hotspot still does not appear, try the browser installer method from a computer with a USB cable and a supported browser.

The captive portal page does not load

  • After connecting to the airlytix-es1-xxxxxx network, some devices open the portal automatically.
  • If it does not open, manually visit http://192.168.4.1 in your browser.
  • Disable mobile data while connected to the ES1 hotspot so your device does not prefer mobile internet.

The web installer cannot find my ES1

  • Use a recent version of Chrome or Edge on desktop.
  • Check that the USB cable supports data (not just charging).
  • When prompted, select the CP2102N USB to UART Bridge Controller device.

If the installer still cannot connect, try a different USB cable or port, or use the hotspot method instead.

Home Assistant discovery problems

ES1 does not show up automatically in Home Assistant

  • Confirm ES1 is connected to your home WiFi (see the WiFi section above).
  • Ensure ES1 and Home Assistant are on the same network/subnet.
  • Restart ES1 by unplugging and re‑plugging USB power.
  • In Home Assistant, go to "Settings" → "Devices & Services" and click "Check for new devices" if available.

If Home Assistant is running on a different VLAN or network segment, automatic discovery may be blocked. In that case, add ES1 manually using the ESPHome integration and IP address.

If ES1 is still not discovered, you can add it manually using the ESPHome integration and the device’s IP address.

I do not know the IP address of ES1

  • Check your router’s DHCP or client list for a device named airlytix-es1-xxxxxx.
  • If you used the web installer, it may show the IP address at the end of the process.

Once you have the IP address, follow the "Manual" tab on the Connecting to Home Assistant page.

Sensor readings look wrong

Readings seem offset compared to another device

  • Small differences between sensors are normal, especially for temperature and humidity.
  • For larger or consistent differences, consider using the offset entities on the Configuration page:
    • Temperature Offset
    • Humidity Offset
    • Ambient Light Offset
  • Adjust in small steps and compare over several hours.

Everything is always showing as Poor

  • Check the Good and Fair ranges on the Configuration page.
  • If you have set very tight ranges, ES1 may classify normal conditions as Poor.
  • Start from the firmware defaults and then adjust gradually.

If you live in an area with consistently poor outdoor air quality or high background VOC/NOx, you may need to widen the Fair band so that "poor" really indicates conditions you care about.

VOC or NOx values seem unstable at first

  • VOC and NOx indices use Sensirion’s learning algorithms and need time to stabilise.
  • Expect readings to settle over the first few hours to days after installation or after large changes in environment.
  • Avoid judging long‑term behaviour from only the first few minutes of data.

If values remain unusually high or low after several days, try:

  • Ensuring ES1 sees fresh outdoor‑like air for at least 30–60 minutes (open windows or move the device temporarily).
  • Power‑cycling ES1 so the algorithm can restart with the improved baseline.

Indicator light issues

The indicator light is off

  • In Home Assistant, check the Indicator Light entity:
    • Ensure it is turned on.
    • Increase brightness if it is set very low.
  • If you prefer a dark room at night, you can turn this entity off without affecting sensor readings.

The indicator light colour does not match my expectations

  • Check the State entity in Home Assistant:
    • good → green, fair → orange, poor → red.
  • If the State is often poor, review your thresholds on the Configuration page.
  • Make sure ES1 has had enough time to collect data after power‑on, especially for VOC and NOx.

If you still have problems after trying these steps, you can open an issue in the Airlytix documentation repository with details about your setup and what you are seeing.

Firmware & Updates