Browse fan and limit controls at Furnace Part Source, including available limit controls, fan and limit switches, insert-style controls, and temperature control components for compatible furnace and HVAC equipment. Match the exact part number, insertion length, temperature range, switch setting, equipment model, and product details before ordering to help confirm the correct replacement.
Lennox® Flame Sensor Part #20J91; Current part number for obsolete Lennox® # 20J9101
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Item Typically Ships within the Same Business Day
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Lennox® Flame Sensor Part #18G89; Current part number for obsolete Lennox® # 18G8901 FurnacePartSource.com Commitment Item Typically Ships within the Same Business Day Brand-New Genuine Parts -...
Lennox® Flame Sensor Part #12F19; Current part number for obsolete Lennox® # 12F1901 FurnacePartSource.com Commitment Item Typically Ships within the Same Business Day Brand-New Genuine Parts -...
Heil Quaker1149856 Pilot Assembly & Flame Sensor
Item is Non Cancelable / Non Returnable
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Item Typically Ships Within the Same Business Day
Brand-New Genuine...
York Controls® S1-025-27773-700 Flame Sensor, aka Part # 025-27773-700
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Item Typically Ships Within the Same Business Day
Brand-New Genuine Parts -...
A furnace flame sensor helps the heating system confirm that a burner flame is present during operation. If the sensor is worn, damaged, dirty, or no longer reading properly, the furnace may fail to complete the heating cycle or may shut down shortly after ignition. This category includes replacement furnace flame sensors, pilot sensors, flame rods, sensor leads, infrared flame heads, and flame sensor assemblies for compatible furnace, boiler, burner, and HVAC equipment.
How to Choose the Right Flame Sensor
Before ordering a replacement flame sensor, compare the product listing with the existing sensor and the equipment documentation. Important details may include the exact part number, sensor length, lead length, rod shape, mounting bracket, terminal style, ceramic body size, wiring connection, brand, and furnace or burner model. Matching by part number is the safest way to confirm the correct replacement, especially when comparing similar-looking flame rods or pilot sensor assemblies.
Universal and Brand-Specific Flame Sensors
Some listings may be brand-specific replacement flame sensors, while others may be universal flame sensor options for compatible applications. A universal furnace flame sensor should still be checked against the original part dimensions, mounting style, and equipment requirements before ordering. Visible listings may include flame sensors and pilot sensor parts from brands such as Bard, York, Rheem-Ruud, Eclipse, Honeywell, Lochinvar, Siemens Combustion, Amana-Goodman, AERCO, and Supco.
When a Flame Sensor May Need Replacement
A flame sensor may need inspection or replacement if the furnace lights briefly and then shuts off, cycles inconsistently, or shows an ignition-related fault code. These symptoms can also be caused by other furnace or ignition system issues, so the flame sensor should be diagnosed according to the equipment manual before replacing parts. For safety, furnace flame sensor replacement should be handled by a qualified HVAC technician when gas, electrical, or burner components are involved.
Confirm Fit Before Ordering
When comparing furnace flame sensor prices or looking for where to buy a flame sensor for a furnace, make sure the replacement matches the system requirements instead of choosing by appearance alone. Check the existing part label, furnace model, service manual, sensor length, lead length, mounting style, and connector type before placing your order. If the original part number is unavailable, use the product details and equipment documentation to help narrow down the correct flame sensor replacement.
