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error Honeywell

Error Code Connection Failure

The thermostat failed to connect to the Wi-Fi network during setup.

? What Causes This

Incorrect Wi-Fi password, router not responding, or network configuration issue.

How to Fix It

  1. Confirm you correctly entered your home network password.
  2. Verify the router has power and internet access.
  3. Refer to FAQ at wifithermostat.com/support.

Source: page 30 of the official manual

From the manual

Manual page 30 — Honeywell error Connection Failure

This error code appears in:

Honeywell RTH6580WF Wi-Fi Smart Thermostat