Thermostat shows E5 and will not connect to Wi‑Fi or Amana smart app

Safety first: This is a low-voltage, low-risk issue, but do not open the thermostat housing beyond the user-removable front unless power is off.

• Step 1 – Check home Wi‑Fi: Confirm your router is powered, broadcasting 2.4 GHz (if required by your Amana smart thermostat), and that other devices can connect.
• Step 2 – Move closer test: If possible, temporarily relocate the router closer to the thermostat or use a Wi‑Fi extender to rule out weak signal.
• Step 3 – Reboot thermostat: Turn off HVAC power at the breaker for 1–2 minutes, then restore. Allow the thermostat to fully boot and attempt Wi‑Fi setup again via the on-screen menu.
• Step 4 – Check network settings: Ensure the Wi‑Fi SSID and password are entered correctly. Disable MAC filtering or add the thermostat’s MAC address to the allowed list in your router.
• Step 5 – Firmware update: If the thermostat allows local firmware update via USB or app, follow Amana’s instructions to update to the latest firmware, which may resolve E5.
• Step 6 – Replace thermostat (if module failed): If E5 persists on multiple known-good networks, the internal Wi‑Fi module on the Amana smart thermostat is likely defective. The module is typically integrated and not field-replaceable; replace the thermostat.

When to call a professional: If you are unsure about router settings or firmware procedures, contact Amana support or a professional installer.