AEG AX91-604 Error Code The App shows my air purifier as unavailable: Meaning, Fixes & Troubleshooting

AEG AX91-604 error code The App shows my air purifier as unavailable means the mobile app cannot reach the purifier over the network or via the AEG cloud. This can be caused by local Wi‑Fi issues, the purifier being offline, incorrect app account or pairing, or temporary cloud/service outages.

• App displays the device as 'unavailable' or 'offline' while the purifier's display appears normal.
• You cannot change settings or see live air-quality/operation status in the app.

• Temporary loss of Wi‑Fi or the purifier not connected to the correct Wi‑Fi network (e.g., 2.4 GHz vs 5 GHz).
• The purifier has lost its connection to the AEG cloud service or the app session needs a re-login.

1. 1
   Verify Wi‑Fi network: confirm router is online and other devices can access the internet. If your router offers separate 2.4 GHz and 5 GHz SSIDs, ensure the purifier is on the 2.4 GHz network (AEG devices commonly require 2.4 GHz).
2. 2
   Check app account and device list: sign out of the AEG app, sign back in, and verify the purifier appears in your device list. If it does not, try the app's 'add device' flow to rediscover it.
3. 3
   Ensure no local network restrictions block the purifier: temporarily disable guest mode, AP isolation, or router firewall rules that prevent local device-to-device traffic.
4. 4
   Factory network reset of the purifier (if available): follow the manual's network reset procedure, then re-run setup in the app. Only perform a factory network reset if pair/setup steps fail and after backing up any custom schedules.

• Trying to connect the purifier to a 5 GHz network when the device requires 2.4 GHz.
• Assuming the purifier is offline when it's a temporary cloud outage—check AEG support status before factory resetting.
• Using mobile data to control the purifier during setup instead of ensuring the phone is on the same local Wi‑Fi.

• Do not repeatedly factory reset the purifier without trying simple reconnection steps first; repeated resets may remove schedules and settings.
• Do not share your Wi‑Fi credentials or AEG account details with untrusted services or people when troubleshooting.

• Unplug the purifier before attempting any internal inspection; do not open sealed housings—refer servicing to qualified technicians.
• Avoid using network troubleshooting tools that require administrative router changes unless you understand those settings; incorrect changes can disrupt home network security.

Contact AEG support if you've completed the steps above (power cycle, Wi‑Fi checks, app re-login, factory network reset) and the purifier still shows unavailable in the app, or if the purifier exhibits hardware faults on its display. Be ready to provide the model (AX91-604), serial number, app screenshots, and a short description of steps already taken.

• Keep router firmware up to date and avoid aggressive router firewalls that block device-to-cloud connections.
• Use a stable 2.4 GHz SSID for smart home devices and reserve a clear, consistent SSID/password for the purifier.
• Periodically check the AEG app and firmware updates for the purifier and apply recommended updates.