This genuine Lennox 99W43 (610414-03) Heat Exchanger Replacement Kit is engineered for long-lasting performance and safe operation in compatible Lennox gas furnace systems. Designed for 65,000–70,000 BTU units, this aluminized steel heat exchanger efficiently transfers heat while resisting corrosion, oxidation, and thermal fatigue. It’s an ideal replacement for restoring proper airflow, heating performance, and system reliability.

This OEM kit maintains original equipment specifications to ensure correct fitment, secure sealing, and safe combustion chamber operation. Perfect for technicians and homeowners seeking a dependable Lennox-manufactured replacement.

 

Key Features:

• Genuine Lennox 99W43 (610414-03) replacement heat exchanger assembly
• Rated for 65K–70K BTU furnace models
• Constructed from high-durability aluminized steel
• Helps restore heating efficiency and consistent performance
• OEM design for proper fit, airflow, and safe combustion operation
• Recommended for preventative maintenance or repairing failed exchangers
• Ideal for HVAC contractors and DIY system repairs
• Backed by Lennox engineering standards

 

Typical Applications:

• Residential forced-air gas furnace systems
• Lennox furnaces requiring a 65/70K BTU exchanger
• Replacement for failed, cracked, or corroded heat exchangers