The Utica-Dunkirk PB00903 Flame Sensor is a specialized mercury flame sensor engineered for precision flame monitoring in cycling pilot ignition systems. As an E-type mercury sensor with a bulb style #19, this component is essential for detecting the presence of a pilot flame and allowing the main gas valve to energize. The 48-inch capillary length provides sufficient reach for various HVAC burner box configurations, making it a versatile OEM replacement part for high-efficiency boilers and furnaces. This mercurial flame detection device is built to withstand high-thermal environments, maintaining a reliable microamp signal to the ignition control board. Utilizing SPDT switch logic, it ensures that the 3-pin plug interface communicates accurate flame-proving status, effectively preventing furnace short cycling or hazardous gas accumulation due to ignition failure. For professional HVAC contractors, replacing a faulty mercury sensor with this Utica-Dunkirk PB00903 ensures system stability and restores optimal combustion performance. Key Benefits: Broad Compatibility: Directly replaces multiple White-Rodgers 3098 series sensors, including the 3098-134 and 3098-161 models. Extended Reach: Features a 48" element length to accommodate deep-seated burner assemblies and complex routing. Precise Detection: Specifically designed as a bulb style #19 to interface correctly with cycling pilot gas valves. Robust Construction: Engineered to handle temperatures up to 1450°F at the bulb tip for long-term flame sensing reliability. Common Questions: Can I use a different bulb style if #19 is unavailable? No, mercury flame sensors must be replaced by cross-referencing the specific model number and bulb style to ensure proper mechanical fit and electrical switching. What are the symptoms of a failing flame sensor? Common indicators include the burner lighting only briefly before shutting down, furnace lockout codes, or short cycling several times within a few minutes. Is cleaning possible for mercury sensors? While cleaning soot from the tip with fine steel wool can temporarily restore a microamp signal, a cracked ceramic base or internal mercury leakage requires immediate replacement. Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
