The Lennox 49L04 (100008-01) Sight Glass is a specialized diagnostic accessory engineered to enhance visibility of the SureLight® ignition system's status indicator. Installed in the furnace cabinet, this sight glass allows technicians and service personnel to easily view the onboard diagnostic LED without removing access panels—streamlining service calls and improving safety.
Featuring a 1.500-inch insert diameter, the sight glass ensures a precise, tight fit into the designated opening, forming a clear and sealed viewing port. Its transparent, heat-resistant material resists high temperatures and mechanical stress, ensuring long-term durability even in harsh furnace environments. Whether used in residential or light commercial Lennox units, this component supports faster troubleshooting and minimizes downtime.
Product Features:
Genuine Lennox Replacement Part: Ensures proper fit and full compatibility with Lennox equipment.
Enhanced Diagnostics: Provides uninterrupted visual access to the SureLight system's LED indicators—critical for reading fault codes and verifying ignition sequences.
Durable Construction: Built to withstand thermal fluctuations and furnace vibrations.
Easy Installation: Simply inserts into the provided sight hole on the furnace cabinet; no special tools required.
Sealing Design: Helps maintain unit integrity by preventing dust, moisture, and debris from entering the cabinet.
Versatile Use: Ideal for use across multiple Lennox models that utilize the SureLight control board.
Specifications:
Model: 49L04
Manufacturer Part Number: 100008-01
Insert Diameter: 1.500 inches
Material Type: Clear, high-temperature-rated polymer or glass
Application: HVAC diagnostics, ignition system monitoring
Mounting Type: Insert style
Make maintenance easier and safer with the Lennox 49L04 sight glass—an essential tool for ensuring your furnace is operating correctly.
Available now at Beenimax.com – your reliable source for authentic Lennox HVAC components.
Why Choose Beenimax.com?
At Beenimax.com, we’re committed to providing HVAC professionals and homeowners with dependable, high-quality parts and exceptional service. Here’s why customers choose us as their go-to supplier for Lennox and other top HVAC brands:
Genuine OEM Parts: We offer only authentic, manufacturer-approved components—no knockoffs, no substitutions. Your system gets the part it was designed for.
Competitive Pricing: Our pricing is fair and transparent, helping you get the most value without sacrificing quality. Discounts are available for contractors and bulk buyers.
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Expert Support: Have questions? Our knowledgeable team is ready to assist with product compatibility, installation tips, and technical specs.
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Contractor Recommended: Trusted by HVAC professionals across the country for consistent service, stocked inventory, and reliable delivery.
Whether you're replacing a single part or managing large-scale repairs, Beenimax.com makes it easy to find what you need—quickly, affordably, and with confidence.
