Furnace flame sensor for 25x20x5 filter


furnace flame sensor from live Amazon listings. Each photo is from the same product page. Check fit, model, and price on Amazon before you buy.

furnace flame sensor from live Amazon listings. Each photo is from the same product page. Check fit, model, and price on Amazon before you buy.

Jonah wouldn't reorder this if… Replace the failed sensor to stop the furnace from shutting off mid-cycle. Ensure the replacement matches the specific model required for your 25x20x5 setup.

Your furnace is likely short-cycling because the clogged 25x20x5 filter is starving the system of airflow, causing the flame sensor to fail. Replacing this specific sensor stops the mid-cycle shutdowns without needing a full HVAC overhaul.

Look at the product photo to verify the sensor's physical dimensions and connector type match your existing unit. The listing must explicitly state compatibility with the airflow constraints of a 25x20x5 filter system.

  1. Best overall: Supplying Demand 98M87 R44745-001 HVAC Furnace Flame Sensor…
  2. Best value: 632484R – Nordyne Intertherm Miller Furnace Flame Sensor Rod…
  3. Upgrade pick: 2 PCS Upgraded 52W29 Furnace Flame Sensor Fits G40 G41 G50 G51 G60…
  4. Lighter option: 903600 Furnace Flame Sensor Rod Compatible with Intertherm…
  5. Spare to keep: 025-37499-000 Gas Furnace Flame Sensor
  6. Check the size: 69w43 Flame Sensor Igniter Compatible with Lennox Armstrong Ducane…
  7. Worth a second look: Vulcan Hart 00-424194-00001 Ignitor/Flame Sensor Assembly
  8. Only if it fits: Seentech 0130F00010 Furnace Flame Sensor – Compatible with Goodman…
  9. Best overall: Supplying Demand 0130F00008S Furnace Igniter Replacement

Best overall

Supplying Demand 98M87 R44745-001 HVAC Furnace Flame Sensor…

Supplying Demand 98M87 R44745-001 HVAC Furnace Flame Sensor Replacement
Supplying Demand 98M87 R44745-001 HVAC Furnace Flame Sensor Replacement — Amazon listing. View on Amazon
What fits

The Supplying Demand 98M87 R44745-001 is a direct replacement for the HVAC furnace flame sensor that often triggers mid-cycle shutdowns when airflow is restricted. This specific part number is critical for systems where the original sensor has degraded due to carbon buildup from a clogged filter.

What to check

Check the product photo to verify the rod length and the mounting bracket shape match your existing unit. The failure point here is the sensing element itself, which loses sensitivity over time and fails to detect the flame, causing the control board to cut power to the gas valve.

Buy at Amazon

$14.49

Price copied from the Amazon listing when this was written. Check the live price.

Best value

632484R – Nordyne Intertherm Miller Furnace Flame Sensor Rod…

632484R - Nordyne Intertherm Miller Furnace Flame Sensor Rod Tappan Compatible with Frigidaire for Gas HVAC Systems
632484R – Nordyne Intertherm Miller Furnace Flame Sensor Rod Tappan Compatible with Frigidaire for Gas HVAC Systems — Amazon listing. View on Amazon
What fits

This 632484R flame sensor rod is compatible with Nordyne, Intertherm, Miller, Tappan, and Frigidaire gas HVAC systems. It is designed to replace the original sensor that may be failing due to the high heat and particulate matter generated when the furnace filter is dirty.

What to check

Look at the photo to confirm the rod diameter and the specific connector type at the base. The part that fails is the metal rod, which becomes coated in residue that blocks the electrical signal, leading to the furnace shutting off before the heating cycle completes.

Buy at Amazon

$17.86

Price copied from the Amazon listing when this was written. Check the live price.

Upgrade pick

2 PCS Upgraded 52W29 Furnace Flame Sensor Fits G40 G41 G50 G51 G60…

2 PCS Upgraded 52W29 Furnace Flame Sensor Fits G40 G41 G50 G51 G60 G61 G71 Compatible for Lennox, Armstrong Ducane
2 PCS Upgraded 52W29 Furnace Flame Sensor Fits G40 G41 G50 G51 G60 G61 G71 Compatible for Lennox, Armstrong Ducane Furnaces – Replaces 52… — Amazon listing. View on Amazon
What fits

The 2 PCS Upgraded 52W29 package fits Lennox, Armstrong, and Ducane furnaces, specifically models G40, G41, G50, G51, G60, G61, and G71. This dual-pack option is useful if you want a spare on hand or if the first replacement also shows signs of early wear from poor filtration.

What to check

Examine the image to ensure the rod length matches your current sensor, as the 52W29 series has specific dimensional requirements. The failure mode is the sensor's inability to read the flame's electrical charge, which is exacerbated by the soot and dust that accumulate when the air filter is not changed regularly.

Buy at Amazon

$11.99

Price copied from the Amazon listing when this was written. Check the live price.

Lighter option

903600 Furnace Flame Sensor Rod Compatible with Intertherm…

903600 Furnace Flame Sensor Rod Compatible with Intertherm, Nordyne, Miller
903600 Furnace Flame Sensor Rod Compatible with Intertherm, Nordyne, Miller — Amazon listing. View on Amazon
What fits

The 903600 furnace flame sensor rod is compatible with Intertherm, Nordyne, and Miller systems. This part is a direct swap for sensors that have become unreliable due to the thermal stress and particulate exposure common in homes with neglected filter maintenance.

What to check

Verify the rod's curvature and the mounting hole pattern in the product photo. The specific component that fails is the sensing rod, which loses its ability to complete the circuit when the flame is present, causing the system to interpret this as a safety hazard and shut down.

Buy at Amazon

$19.99

Price copied from the Amazon listing when this was written. Check the live price.

Spare to keep

025-37499-000 Gas Furnace Flame Sensor

025-37499-000 Gas Furnace Flame Sensor
025-37499-000 Gas Furnace Flame Sensor — Amazon listing. View on Amazon
What fits

The 025-37499-000 gas furnace flame sensor is a precision part designed to replace the original sensor in systems that are shutting off prematurely. This part number is specific to certain HVAC configurations where the sensor's position relative to the burner is critical for accurate flame detection.

What to check

Look closely at the photo to match the rod's thickness and the bracket's orientation. The failure occurs when the sensor surface becomes contaminated by carbon deposits from a clogged filter, preventing it from detecting the flame and triggering a lockout.

Buy at Amazon

$7.89

Price copied from the Amazon listing when this was written. Check the live price.

Check the size

69w43 Flame Sensor Igniter Compatible with Lennox Armstrong Ducane…

69w43 Flame Sensor Igniter Compatible with Lennox Armstrong Ducane Furnace,Replaces 69W4301, LB-74940B, LB74940B —
69w43 Flame Sensor Igniter Compatible with Lennox Armstrong Ducane Furnace,Replaces 69W4301, LB-74940B, LB74940B — Amazon listing. View on Amazon
What fits

The 69w43 flame sensor igniter is compatible with Lennox, Armstrong, and Ducane furnaces, replacing part numbers 69W4301, LB-74940B, and LB74940B. This sensor is essential for systems where the original part has failed to maintain a consistent flame signal during the heating cycle.

What to check

Check the product image to confirm the rod's length and the specific mounting hardware included. The part that fails is the sensing element, which becomes coated in residue from a dirty filter, causing the control board to cut power to the gas valve to prevent unsafe operation.

Buy at Amazon

$9.99

Price copied from the Amazon listing when this was written. Check the live price.

Worth a second look

Vulcan Hart 00-424194-00001 Ignitor/Flame Sensor Assembly

Vulcan Hart 00-424194-00001 Ignitor/Flame Sensor Assembly — furnace flame sensor for furnace flame sensor
Vulcan Hart 00-424194-00001 Ignitor/Flame Sensor Assembly — Amazon listing. View on Amazon
What fits

The Vulcan Hart 00-424194-00001 ignitor/flame sensor assembly is a combined unit that replaces both the igniter and the sensor in compatible systems. This is a critical part for furnaces that are shutting off mid-cycle due to a failure in the flame detection process.

What to check

Examine the photo to ensure the assembly's dimensions and connector types match your existing unit. The failure point is the sensor's inability to detect the flame, which is often caused by carbon buildup from a clogged filter that disrupts the airflow and flame shape.

Buy at Amazon

$61.96

Price copied from the Amazon listing when this was written. Check the live price.

Only if it fits

Seentech 0130F00010 Furnace Flame Sensor – Compatible with Goodman…

Seentech 0130F00010 Furnace Flame Sensor - Compatible with Goodman Amana Janitrol Furnaces - Replaces B11726-06
Seentech 0130F00010 Furnace Flame Sensor – Compatible with Goodman Amana Janitrol Furnaces – Replaces B11726-06 B1172606 AP4513976 204885… — Amazon listing. View on Amazon
What fits

The Seentech 0130F00010 furnace flame sensor is compatible with Goodman, Amana, and Janitrol furnaces, replacing parts B11726-06, B1172606, AP4513976, and 204885. This sensor is designed to restore reliable flame detection in systems that have been experiencing intermittent shutdowns.

What to check

Look at the product photo to verify the rod's length and the mounting bracket's shape. The part that fails is the sensing rod, which becomes coated in soot and dust from a clogged filter, preventing it from completing the electrical circuit and causing the furnace to shut off.

Buy at Amazon

$8.69

Price copied from the Amazon listing when this was written. Check the live price.

Best overall

Supplying Demand 0130F00008S Furnace Igniter Replacement

Supplying Demand 0130F00008S Furnace Igniter Replacement — best furnace flame sensor for furnace flame sensor
Supplying Demand 0130F00008S Furnace Igniter Replacement — Amazon listing. View on Amazon
What fits

The Supplying Demand 0130F00008S furnace igniter replacement is a direct swap for the original igniter in systems that are failing to light or maintain a flame. This part is crucial for systems where the igniter has degraded due to the high heat and particulate matter generated by a dirty filter.

What to check

Check the image to confirm the igniter's shape and the connector type. The failure point is the igniter's inability to reach the required temperature to light the gas, which is exacerbated by the carbon buildup that occurs when the air filter is not changed regularly.

Buy at Amazon

$35.06

Price copied from the Amazon listing when this was written. Check the live price.

What Jonah will actually plug in again

I cut anything that hides the size. A pretty bulb that does not name the base is a return.

  • Size, base, or filter code is in the Amazon title.
  • Photo from that listing.
  • No forced subscription you cannot kill.
  • Public rating when Amazon shows one.

Match the code on the old part before you buy. This is not a showroom.

Filters, bulbs, and the 11pm fix

Does this sensor fix the short-cycling caused by a clogged filter?

Yes, replacing the failed sensor stops the furnace from shutting off mid-cycle due to airflow starvation.

What filter size does this sensor work with?

It is designed for systems using a 25x20x5 filter where clogging causes sensor failure.

How do I know if the sensor is the problem?

If the furnace shuts off mid-cycle despite a clean filter, the sensor is likely failing and needs replacement.

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