Diagnosis
The issue is not a failure of the thermostat hardware or the local Wi-Fi connection, but rather a failure of the cloud-based authentication handshake between your new device and the Johnson Controls (JCI) cloud servers. Because the GLAS thermostat remains functional on the wall, we know the device is still authenticated with your home router and is actively communicating with the JCI backend. The "cannot find" error on your new phone occurs because the app is attempting to scan for a local broadcast signal (which is only active during the initial pairing mode) instead of pulling the device list from your registered account. This typically happens because users attempt to "Add Device" on a new phone as if they were installing the thermostat for the first time. The GLAS system uses a unique hardware ID linked to a specific email address; unless you are logged into the exact account that originally provisioned the device, the app will not "see" the thermostat on the network. Additionally, if you migrated from an older Android or iOS version, cached credentials or outdated app versions can prevent the secure token exchange required to authorize a new mobile device.
How to Fix It
To restore connectivity on your new mobile device, follow these precise steps to ensure the cloud synchronization is triggered correctly:
- Delete any legacy "GLAS" apps from your phone. Navigate to the App Store (iOS) or Google Play Store (Android) and download the current Johnson Controls Home app.
- Launch the app and select Sign In. Do not select "Create Account" or "Add Device." Use the exact email address and password used during the initial installation.
- Once logged in, navigate to the Devices tab. If the thermostat does not appear immediately, force-close the app (swipe up/away) and relaunch it to trigger a refresh of the cloud device list.
- If the device appears but shows as "Offline," go to the physical GLAS thermostat on the wall. Tap the Settings icon (gear) > Network and verify that the Wi-Fi signal strength is at least 2 bars.
- On your phone, ensure that Local Network Access is enabled for the Johnson Controls Home app in your phone's system settings (Settings > Johnson Controls Home > Toggle "Local Network" to ON).
If That Didn't Work
- Perform a Soft Reset: If the app is logged in but cannot sync, perform a soft reboot of the thermostat. Gently pull the GLAS faceplate off the wall mounting bracket, wait 30 seconds, and snap it back into place. This forces the device to re-establish its secure tunnel to the JCI cloud without erasing your settings.
- Verify 2.4GHz Band: Ensure your new phone is connected to the same SSID as the thermostat. If your router uses "Smart Connect" (merging 2.4GHz and 5GHz), the phone may be on 5GHz while the thermostat is on 2.4GHz, causing a local discovery failure. Temporarily disable the 5GHz band on your router to see if the app connects.
- Account Recovery: If you cannot remember the exact email used, check your inbox for the original "Welcome to GLAS" confirmation email. The account is case-sensitive; ensure there are no trailing spaces in the email field during login.
- Clear App Cache: On Android devices, go to Settings > Apps > Johnson Controls Home > Storage > Clear Cache and Clear Data. This removes corrupted tokens from the new phone's local storage that may be blocking the authentication process.
Heads Up
- Avoid Factory Resets: Do not perform a "Factory Reset" on the wall unit unless absolutely necessary. Doing so deletes the cloud pairing and will require you to go through the entire commissioning process again, including re-entering your HVAC equipment profiles.
- Firmware Updates: Once connected, check for firmware updates in the app. Outdated GLAS firmware can lead to intermittent "Device Offline" errors when using newer smartphone OS versions.
- Battery Health: If your GLAS unit is powered by a C-wire, ensure the voltage is stable. Low power can cause the Wi-Fi chip to drop connections, making the device appear missing to the app even when the screen is on.