Furnace emits a burning smell or plastic smell when running

Safety first: If you see smoke or suspect fire, switch off power immediately and contact emergency services.

• Initial use: A slight smell on first use or after long inactivity can be normal as dust burns off. This should dissipate after a short period.
• Inspect interior: With power off, remove the cover and look for discolored wiring, melted insulation, or foreign objects near hot parts.
• Tighten connections: A qualified technician should check and tighten electrical terminals on the PCB, pump, and fan.
• Replace overheating components: If a motor or component shows signs of overheating, replace it with a genuine Saunier Duval part.