Furnace will not start; status LED flashes 1 time repeatedly on the control board.

Safety first: Turn off power to the furnace at the service switch and shut off gas at the gas shutoff valve before removing panels. If you ever smell strong gas, evacuate and contact the gas utility or fire department.

• Check thermostat call for heat: Set thermostat to HEAT and raise the setpoint 5°F above room temperature. Verify the furnace is actually being called to run.
• Verify gas supply: Make sure the manual gas shutoff valve near the furnace is parallel to the pipe (ON). Confirm other gas appliances in the home work.
• Inspect hot surface ignitor: Remove the burner compartment door. Locate the ignitor (usually a ceramic element near the burners). Look for cracks, white spots, or breaks. If damaged, replace with an OEM Amana-compatible hot surface ignitor.
• Clean flame sensor: Locate the flame sensor rod at the burner. Remove the mounting screw, pull the rod, and gently clean it with fine steel wool or emery cloth until shiny. Reinstall firmly.
• Check wiring to gas valve: Inspect the harness from the control board to the gas valve for loose or damaged wires. Reseat connectors.
• Restore power and test: Turn gas and power back on, then call for heat and watch the ignition sequence through the sight glass. If the ignitor glows but burners never light, suspect the gas valve. If nothing glows, suspect the ignitor or control board.

If the furnace repeatedly locks out after several attempts, contact a qualified HVAC technician to test gas pressure and control board outputs.