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Lennox 21L99 Flame Sensor for Gas Furnaces

Part of: Lennox Flame Sensor for Gas Furnaces

Other options in this family: Lennox 17J56 Lennox 12L09 Lennox 39F95 Lennox 18G89 Lennox 32M86

Manufacturer

Picture for manufacturer Lennox

Part Number

21L99
6 reviews
Sale Price

$16.95

In Stock (10+)

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Usually delivered within 2 days

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Live-in-stock inventory

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Fitment guaranteed

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Product Details

The Lennox 21L99 is a genuine OEM flame sensor designed for Lennox gas furnaces. This critical safety component monitors the presence of flame during furnace operation, ensuring proper ignition and safe combustion.

Key Features:

  • Genuine Lennox OEM replacement part for reliable performance
  • Detects flame presence to verify proper ignition and prevent gas buildup
  • Direct replacement for worn or failed flame sensors
  • Essential safety component that prevents furnace operation without proper flame
  • Compatible with various Lennox gas furnace models

The flame sensor works by detecting the electrical current generated by the flame. When the sensor becomes coated with carbon deposits or fails, the furnace will not stay lit or may short cycle. Regular inspection and replacement of this component ensures safe, reliable furnace operation and helps prevent nuisance shutdowns during the heating season.

Great price. Shipped within 2 day period. Very satisfied

very quick purchase looks like the product i"m looking for.

When I ordered the item from the website it did not indicate it was a backordered product When I called customer service the # provided would only hang up. I then emailed and it took 3 days for a response via email only to tell me the item WAS backordered and wouldn't be available until July 2022. I chose not to cancel and was surprised it showed up a few weeks later. I'm glad I got the product, but overall not happy with the hoops I jumped through to find out what was going on. I won't be ordering from this company again

Easy to find what was needed and great prices on items

I'm glad I found y'all and the part fit perfect! I'll be shopping with you again!

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