Strong chemical or burning smell when the furnace runs.

Safety: If you smell burning plastic or see smoke, turn off power and gas immediately and investigate before further operation.

Steps:

• New furnace smell: A mild odor is normal for the first few hours of operation on a new Keeprite furnace as oils burn off.
• Check filter and airflow: Replace dirty filters and open all registers to prevent overheating.
• Inspect ducts: Look into accessible supply registers for plastic, toys, or other debris.

Persistent strong odors or signs of overheating require professional inspection to rule out electrical or heat exchanger issues.