Strong metallic, electrical, or plastic burning smell from furnace during operation.

Warning: Turn off power at the breaker immediately if you smell strong burning or see smoke. Do not continue operating the furnace.

• Step 1 – Inspect blower motor: After power is off and components have cooled, check the blower motor for discoloration, burnt smell, or melted wiring.
• Step 2 – Check wiring: Inspect harnesses around the control board, blower, and inducer for melted insulation or arcing marks. Repair or replace damaged wiring.
• Step 3 – Test capacitor: For PSC motors, test the run capacitor and replace if bulged or out of spec.
• Step 4 – Professional evaluation: Due to fire risk, have a qualified technician fully inspect and test the Tempstar furnace before returning it to service.