> For the complete documentation index, see [llms.txt](https://help.aranet.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.aranet.com/aranet-home-app/aranet-home-app/troubleshooting.md). # Troubleshooting ## Bluetooth/Pairing issues ### Long pairing time Bluetooth pairing usually takes about 5 to 15 seconds. If it takes more than 60 seconds or an error message appears on the screen of the device, the pairing process has likely crashed. This can also be the cause of not receiving the PIN code. {% hint style="warning" %} Don't close the app while pairing with the sensor. {% endhint %}
Troubleshooting steps for Aranet4/Aranet2/Aranet Radiation * Check whether all necessary permissions are set to *Allow.* * Restart your phone or device and repeat the pairing process.\ Here is the information about the correct pairing process: [Pairing Process](/aranet-home-app/aranet-home-app/pairing-process.md) * If the previous steps don't help: * Take out the batteries of the Aranet device. * Set the jumper switch in the battery compartment for Bluetooth service to the OFF (down)position, then back to the ON (Up) position. * Make sure the 4th switch is in the OFF (down) position. * Put the batteries in the correct polarisation again inside the Aranet. * Uninstall the Aranet Home app completely and delete/forget the paired Aranet device from Bluetooth connected devices on the mobile device. * Install the application again and pair the Aranet device to the mobile device, not via the Bluetooth devices menu, but only via the Aranet Home application. * If the issue persists, please contact or fill out the [RMA](https://rma.aranet.com/) form.
Troubleshooting steps for Aranet Radon Plus * Check whether all necessary permissions are set to *Allow.* * Restart your phone or device and repeat the pairing process.\ Here is the information about the correct pairing process: [Pairing Process](/aranet-home-app/aranet-home-app/pairing-process.md) * If the previous steps don't help: * Take out the batteries of the Aranet device to "restart" it. * Using the side switch, locate the Bluetooth settings. * Turn the Bluetooth to OFF and then back to ON. * Carefully clean the battery contacts. * Put the batteries in the correct polarity again inside the Aranet. * Uninstall the Aranet Home app completely and delete/forget the paired Aranet device from Bluetooth connected devices on the mobile device. * Install the application again and pair the Aranet device to the mobile device, not via the Bluetooth devices menu, but only via the Aranet Home application. * If the issue persists, please contact or fill out the [RMA](https://rma.aranet.com/) form.
Troubleshooting steps for Aranet Radon One * Check whether all necessary permissions are set to *Allow.* * Restart your phone or device and repeat the pairing process.\ Here is the information about the correct pairing process: [Pairing Process](/aranet-home-app/aranet-home-app/pairing-process.md) * If the previous steps don't help: * Take out the batteries of the Aranet device to "restart" it. * Using the built-in buttons, locate the Bluetooth settings. * Turn the Bluetooth to OFF and then back to ON. * Carefully clean the battery contacts. * Put the batteries in the correct polarity again inside the Aranet. * Uninstall the Aranet Home app completely and delete/forget the paired Aranet device from Bluetooth connected devices on the mobile device. * Install the application again and pair the Aranet device to the mobile device, not via the Bluetooth devices menu, but only via the Aranet Home application. * If the issue persists, please contact or fill out the [RMA](https://rma.aranet.com/) form.
### Can't find the sensor If your phone doesn't find Aranet sensors, please try downloading the nRF app for [iOS](https://apps.apple.com/us/app/nrf-connect-for-mobile/id1054362403) or [Android](https://play.google.com/store/apps/details?id=no.nordicsemi.android.mcp) and see if the Aranet doesn't send the Bluetooth signal. If the app shows that the Aranet device is found, then the Bluetooth transmitter is operational; if not, then please fill out the [RMA](https://rma.aranet.com/) form. ## Calibration issues It is possible to calibrate the Aranet4 via the Home app. In cases when the calibration has occured an failure, please try these steps.
General troubleshooting steps * Remove the batteries for 5+ minutes and try the calibration again. * If the calibration is still not possible and an error is still shown on the screen of the device, then please fill out the [RMA](https://rma.aranet.com/) form.
The calibration process was interrupted If your device got empty battery while calibrating the device, the calibration will not fail. As soon as the device is turned on and the Home app is opened, the calibration will begin from the point where it was stopped.
Calibration errors and their solutions
Error codeCauseSolution
Unstable environmentDuring the calibration process of the Aranet4 device, the CO₂ concentration level changes in the surrounding air were too large for the device to correctly set the 420 ppm calibration baseline.Try the calibration again in an outdoor environment during the calibration process for 15 minutes without any person nearby.
0x8001 – 0x8005The CO₂ sensor is damagedFill out the RMA form
0x8106, 0x800E – 0xFFFE

CO₂ sensor malfunction or CO₂ measurement is out of range, caused by:

- Excessive CO₂ concentration near the device

- Excessive moisture near the device

-Incorrect calibration of CO₂ sensor

- Damaged CO₂ sensor

1. Let the Aranet4 device dry completely

2. Manually recalibrate the CO₂ sensor

3. If the problem persists, fill out the RMA form.

Displaying 0ppm or 9999ppmThe CO₂ sensor is misadjusted or damaged

1. Manually recalibrate the CO₂ sensor

2. If the problem persists, fill out the RMA form.

--- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://help.aranet.com/aranet-home-app/aranet-home-app/troubleshooting.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.