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Common Errors

Last updated April 24, 2026


Dashboard Errors

"No data" on SensorStat card

Cause: The sensor is not publishing readings to Firebase RTDB.

Fix: Check that the flow is deployed, the Pi is online, and the sensor is wired correctly. See Sensor Not Reporting.

"Device offline" indicator

Cause: The Pi has not sent a heartbeat to Firebase recently.

Fix: Check network connectivity and Pi power. See Device Offline.

"Command timeout" on ActuatorToggle

Cause: The Pi did not acknowledge the actuator command within the timeout window.

Fix: Check that the Pi is online and Node-RED is running. Click Retry to re-send the command.

Stale sensor readings (yellow dot)

Cause: The sensor reading has not updated within the expected polling interval.

Fix: This may be transient. If it persists, check the Pi's Node-RED logs for sensor read errors.

Configurator Errors

"Deploy failed" with no specific error

Cause: Generic deploy failure, usually a communication timeout.

Fix: Verify the Pi is online, wait 30 seconds, and retry. See Deploy Failures.

"Invalid configuration" on a part

Cause: A required field is missing (GPIO pin, I2C address, etc.).

Fix: Click the flagged part and fill in all required fields.

"Duplicate sensor ID" warning

Cause: Two sensors in the same room have the same identifier.

Fix: Rename one of the sensors or move it to a different room.

Account and Auth Errors

"Session expired" redirect to login

Cause: Your Firebase auth token expired and auto-refresh failed.

Fix: Sign in again. If this happens frequently, check for browser extensions blocking cookies.

"Permission denied" on save

Cause: Your role does not have write access to this resource.

Fix: Check your role (owner, editor, viewer) with the device owner. Viewers have read-only access.

"Device limit reached" when adding a device

Cause: You have reached the maximum devices for your subscription tier.

Fix: Upgrade your plan from Account Settings > Billing, or remove an unused device.

"Sensor slot limit reached" when adding parts

Cause: You have reached the sensor slot limit for your tier.

Fix: Upgrade your plan or remove unused sensors from your configuration.

Pi and Node-RED Errors

Node-RED will not start

Check logs:

sudo journalctl -u nodered --since '10 min ago'

Common causes:

  • Port 1880 already in use (another Node-RED instance running)
  • Corrupted flow file
  • Missing Node-RED nodes/packages

Fix: Restart Node-RED: sudo systemctl restart nodered. If the flow file is corrupted, redeploy from the Configurator.

Firebase connection errors in Pi logs

Cause: The Pi cannot authenticate with Firebase.

Fix: The agent refreshes tokens automatically. If errors persist, restart the agent: sudo systemctl restart loopstring-agent

"Cannot read sensor" errors

Cause: Hardware communication failure.

Fix: Check wiring, verify the correct GPIO/I2C/UART configuration, and ensure the sensor is powered.

Getting More Help

If your issue is not covered here:

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