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$16.70 each
In Stock
Get 55 Thu, Jun 25
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Description
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Lennox 52W29 Flame Sensor Kit (LB-74940A) is an OEM flame sensing kit used on selected Lennox gas furnaces to monitor burner flame presence and allow the control board to safely prove flame during operation.
Key Features:
Compatibility & Applications:
Installation & Operation Notes:
Maintenance & Troubleshooting:
Key Features:
- OEM Lennox flame sensor kit, part number 52W29 (LB-74940A)
- Designed to detect burner flame and signal the furnace control board
- Includes flame sensor assembly and associated hardware as supplied in the kit
- Replacement part matched to specific Lennox furnace models listed in Lennox documentation
Compatibility & Applications:
- Intended for use on Lennox gas furnaces that specify 52W29 / LB-74940A in the official parts list
- Used when diagnostic codes or service checks indicate a failed or weak flame sensor signal
- Suitable for residential forced air gas furnaces where the original flame sensor has become contaminated, cracked, or otherwise unreliable
Installation & Operation Notes:
- Disconnect power to the furnace and shut off gas supply before servicing
- Follow Lennox service instructions for accessing the burner compartment and removing the existing flame sensor
- Install the new flame sensor in the same mounting location and orientation, reusing or replacing mounting hardware as supplied in the kit
- Route and connect the sensor lead to the control board flame sensor terminal as originally configured
- After installation, restore power and gas, then verify proper ignition sequence and stable flame sensing through a complete heat cycle
Maintenance & Troubleshooting:
- Inspect the flame sensor during annual furnace maintenance for signs of buildup or damage
- Light surface deposits can sometimes be cleaned using the procedure approved by the furnace manufacturer, but heavily worn or cracked sensors should be replaced
- Persistent flame sense or lockout issues after sensor replacement may indicate burner, grounding, or control board problems that require further diagnosis
Questions?
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Call or text 888-757-4774
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Product Reviews
4.94 out of 47 reviews
100% would recommend this product
5 star
94%
4 star
6%
3 star
0%
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1 star
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Showing 1-10 of 47 reviews
I would buy this product again.
Flame sensor is Lennox oem - works great and extras purchased are no problem years later. Lasts easily couple of years installed. Worth the extra cost versus generics.
Mac
Painesville, OH
3 months ago
Verified Buyer
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I will
Great part for furnace
Tony Garate
Kalamazoo, MI
4 months ago
Verified Buyer
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Flame sensor
Great price, fast shipping. Took less than five minutes to install and save me the cost of a service call.
Chuck
Cleveland
4 months ago
Verified Buyer
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perfect for my furnace and very cost effective
It fit right in and solved the occasional failure I was getting
MKCM MLD
Fort Laramie, Wyoming
1 years ago
Verified Buyer
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I would buy this product again
Work as Supposed to
Tony b
Clinton Twp Michigan
1 years ago
Verified Buyer
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Good quality and fast delivery
Great price good quality
Jc climate control
Chicago Illinois
2 years ago
Verified Buyer
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Good Product
Not much to say. It's a flame sensor. It has beed working great for a month or so now.
Dave
St. Louis Mo.
2 years ago
Verified Buyer
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Great experience
First time purchase. Correct part was sent, direct fit. Everyone recommends them so I decided to try them out as well. Would recommend too.
Steve K
Chicago IL
3 years ago
Verified Buyer
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Exact Part I Needed
My buddy, an HVAC contractor, cleaned my furnace for me and told me the only piece he'd replace was the flame sensor. It was easy to install, the furnace has stopped cutting out after a long time running. Your order process is easy, I found the part and had it shipped for $20 less than what the Lennox supplier was going to sell it for.
Bill
Omaha, NE
4 years ago
Verified Buyer
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Very quick delivery , right product
Use it in my furnace , would by from you again
Eva
Cleveland oh
4 years ago
Verified Buyer
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