The Reznor 147165 Flame Sensor is a critical OEM replacement component engineered for precise flame rectification within the burner assembly. Designed specifically for Reznor FT30-300 models and compatible with UDAP and UDAS series unit heaters, this 3-5/8 inch sensor ensures the control board receives a steady DC microamp signal during the ignition cycle. In commercial and industrial HVACR applications, a fouled or oxidized sensor is the primary cause of intermittent 3-second shutdowns. This genuine Reznor part features a high-grade porcelain insulator to prevent voltage leakage and a durable stainless steel rod optimized for high-temperature environments. Swapping a worn sensor for a new 147165 helps prevent gas valve lockout and ensures reliable combustion performance throughout the heating season. Maintaining proper grounding on the mounting surface is essential for the sensor to accurately complete the feedback loop to the furnace control system. Key Benefits Direct OEM Replacement: Guaranteed fit for Reznor FT30-300, UDAP, and UDAS series gas-fired heaters. Precise Flame Detection: Minimizes nuisance lockout codes and prevents unburned fuel accumulation. Rugged Construction: Industrial-grade flame rod and porcelain insulator designed for continuous thermal stress. Enhanced Safety: Immediately signals the ignition control board to shut down gas flow if flame signal is lost. Professional Grade: Specifically designed for commercial HVAC maintenance and rapid field replacement. Common Questions What are the symptoms of a failing Reznor 147165? The most common indicator is the "short cycling" effect where the burner ignites for several seconds and then shuts down. This typically repeats for three attempts before the control board enters a hard lockout. Professionals should check for a DC microamp reading between 2.0 and 6.0 µA using a multimeter in series. Can I clean this sensor instead of replacing it? While light oxidation can sometimes be removed with a dollar bill or very fine emery cloth, heavy carbon buildup or silica coating from airborne contaminants often necessitates a full replacement. If the porcelain insulator is cracked, the sensor must be replaced immediately to prevent electrical shorts to the burner ground. Does this fit older Reznor unit heaters? This sensor is a standard component for many Nortek Global HVAC products. Always verify the part number against your specific unit's wiring diagram or data plate, as different series may require varying rod lengths or terminal connector sizes. 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.
