Strong smoke or burning odor from furnace or vents without visible smoke in room.

Safety first: If you smell strong burning plastic or electrical odor, turn off and unplug the furnace immediately and inspect for overheating components.

Steps:

• 1. New unit burn-in: For new installations, some odor is normal during the first few hours of operation as paint and oils burn off. Operate the furnace on a higher setting with windows slightly open for ventilation.
• 2. Clean dust: Dust on the heat exchanger or cabinet can cause odor. With power off and the unit cool, vacuum dust from accessible surfaces.
• 3. Check for overheating motors: Smell near the convection and combustion blowers. If a motor housing is extremely hot or smells burnt, replace the blower.
• 4. Verify settings: Ensure the furnace is not set to an excessively high feed rate that could cause overheating. Follow US Stove guidelines for maximum settings.
• 5. If odor persists: Have a technician inspect wiring, motors, and controls for signs of overheating or damage.