To address the issue with your SmartRent wall unit displaying an error code and your inability to control the temperature or features via phone, you can follow these steps:

1. Identify the Error Code:
Check the exact error code displayed on your wall unit. This information can be crucial for troubleshooting. Each error code corresponds to specific issues that may require different solutions.

2. Reference SmartRent Troubleshooting Resources:
Visit the SmartRent support page which provides a comprehensive library of articles and troubleshooting tips. You can look for the specific error code on their help section or general troubleshooting guidelines - learn more.

3. Check Wi-Fi Connectivity:
Ensure the wall unit is connected to a stable internet connection. If you suspect connectivity issues, restart your router and the wall unit.

4. Restart the Wall Unit:
Power cycle the wall unit by unplugging it for about 10 seconds and then plugging it back in. This can often resolve temporary malfunctions.

5. Verify Mobile App Settings:
Open your SmartRent mobile app and check whether the app is connected to the wall unit. Sometimes, it may require a logout and login to refresh the connection.

6. Reset to Default Settings:
If the error persists, you may want to reset the wall unit to factory settings. Instructions on how to do this can usually be found in the user manual or on the troubleshooting section of the SmartRent support site.

7. Contact SmartRent Support:
If none of the above steps resolve the error code or restore functionality to your phone controls, reaching out to SmartRent’s customer support would be advisable. You can find contact information on their website - learn more.

8. Follow User Guides and Community Support:
You might find additional insights by checking community forums or user guides related to SmartRent products to see if others have experienced similar issues - learn more.

By following these steps, you should be able to troubleshoot the error effectively. If the problem continues, professional assistance will help ensure your system functions as intended.