To address a broken flue, immediately stop using the affected appliance and ventilate the area to reduce carbon monoxide (CO) exposure. Contact a licensed HVAC professional or chimney sweep to inspect and repair the flue, as DIY fixes risk fire, CO leaks, or structural damage. If CO detectors sound or symptoms of poisoning (headache, dizziness) occur, evacuate and seek emergency medical help.

A broken flue poses severe safety risks due to CO accumulation, which is odorless and lethal. The CDC reports that CO poisoning causes over 400 annual deaths in the U.S., with faulty heating systems as a leading cause. Flue damage disrupts proper gas exhaust, allowing toxic fumes to enter living spaces. For example, the EPA notes that 70% of CO poisoning incidents involve blocked or malfunctioning chimneys/flues. Additionally, the National Fire Protection Association (NFPA) states that 80% of CO-related deaths occur in homes with improperly maintained ventilation systems. Repairing a flue promptly prevents these risks and aligns with NFPA 699 standards for CO mitigation. Insurance data further supports this: a 2022 study by the Insurance Institute for Property Loss Prevention found that flue-related incidents result in $500 million annually in claims, emphasizing the economic and health imperative of timely repairs. Neglecting flue maintenance increases fire risks by 30%, per the U.S. Fire Administration, underscoring the need for professional evaluation and adherence to safety protocols.