What is a Flame Sensor?

The flame sensor is a small, yet crucial component in your furnace's operation, playing a vital role in ensuring your home's safety and comfort. Essentially, it's a safety device designed to detect the presence of a flame in the burner assembly. When your furnace ignites, the flame sensor sends a tiny electrical current through the flame. If a flame is present, the current completes a circuit, signaling to the furnace's control board that it's safe to continue operating and providing heat. Without a working flame sensor, your furnace wouldn't be able to confirm successful ignition, leading to it shutting down as a safety precaution, preventing the dangerous accumulation of unburnt gas.

When a flame sensor malfunctions, your furnace may short-cycle, fail to ignite, or not produce heat at all. Common issues include a buildup of soot or corrosion on the sensor, which can interfere with its ability to detect the flame, or a cracked porcelain insulator. Regular maintenance is key to preventing these issues and ensuring your furnace runs safely and efficiently. If you're experiencing problems with your furnace's ignition or heating, it could be a flame sensor issue. BRAVO HVAC specializes in diagnosing and resolving all HVAC-related problems, including flame sensor replacements and furnace tune-ups, to ensure your system operates reliably and safely.

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