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error Honeywell

Error Code E01

During Wi-Fi setup, the router lost power. The thermostat cannot complete the Wi-Fi connection process.

? What Causes This

Router lost power during setup or Wi-Fi connection attempt.

How to Fix It

  1. Ensure your router has power.
  2. If connecting to a hidden or manually added network, confirm the router has power and is working.
  3. Restart the setup process.

Source: page 61 of the official manual

From the manual

Manual page 61 — Honeywell error E01

This error code appears in:

Honeywell RTH6580WF Wi-Fi Smart Thermostat