Thermostat shows E13 and indoor fan does not respond correctly to commands

Safety first: Turn off power to the furnace/air handler at the breaker before working on wiring.

• Step 1 – Test fan from thermostat: Set the fan mode to ON at the thermostat. If E13 appears and the fan does not run, proceed with wiring checks.
• Step 2 – Inspect G wire at thermostat: Remove the thermostat and verify the G conductor is firmly connected and not broken.
• Step 3 – Inspect G wire at furnace/air handler: At the Amana control board, ensure the same color wire is connected to the G terminal. Tighten the screw.
• Step 4 – Bypass thermostat (advanced): With power on, briefly jumper R to G at the Amana control board. If the fan runs, the board and blower are good and the issue is likely with the thermostat or G wire. If the fan does not run, the fan relay or blower motor circuit is faulty.
• Step 5 – Replace thermostat or repair wiring: If the fan runs with R-G jumper but not via the thermostat, repair or replace the G conductor or replace the thermostat if wiring is intact.

When to call a professional: If the blower does not run even with R-G jumpered, an HVAC technician should diagnose the Amana blower motor and control board.