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Burning smell when the heat first comes on

Dust settled on the heat exchanger or electric heat strips burns off at the first firing and fades within a few hours. A smell that lingers, or smells like plastic, rubber, hot wiring or gas, is not normal and needs diagnosis.

Cross-checked ~30 min easyBrands: All

Before you start

  • Gas smell, CO alarm or headaches: leave the building and call the gas utility or 911. Gas work is blocked: refer to a licensed technician.
  • Turn off power to the furnace before inspecting the blower or wiring.

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Burning smell when the heat first comes on · OnCall Tech