Lennox 25B34 – 62534703 Burner Box UH Assembly, 80 Percent Closed, OEM Replacement Heating Component

 

Product Description 

 

The Lennox 25B34 (62534703) Burner Box UH Assembly is an OEM heating component designed for 80% efficiency natural gas and propane furnaces. This burner box ensures stable combustion, proper flame distribution, and consistent ignition performance across compatible Lennox residential and light commercial units. Manufactured to Lennox quality standards, this 80 percent closed burner assembly helps maintain optimal furnace efficiency, reduces heat loss, and supports long-term reliability during peak heating demand.

Engineered for direct replacement of older or damaged burner box assemblies, the Lennox 25B34 burner housing delivers correct airflow management and sealed combustion alignment inside the unit. Its durable steel construction, factory-calibrated fitment, and original mounting geometry make installation straightforward for HVAC professionals. Ideal for restoring safe furnace operation, improving heat output, and preventing ignition issues or incomplete combustion.

This assembly is commonly used in Lennox mid-efficiency gas furnaces and replaces the original 62534703 burner box configuration without modification. It is a genuine OEM component, ensuring compatibility, proper flame carryover, and long service life.

 

Key Features

 

• OEM Lennox 25B34 burner box assembly
• Part number 62534703, 80 percent closed configuration
• Supports stable and consistent combustion performance
• Heavy-duty steel housing for durability and heat resistance
• Ensures proper airflow, ignition alignment, and flame distribution
• Direct-fit replacement for compatible Lennox 80% furnaces
• Restores heating efficiency and operational safety

 

Specifications

 

• Manufacturer: Lennox
• OEM Part Number: 25B34
• Alternate/Factory Number: 62534703
• Component Type: Burner Box UH Assembly
• Configuration: 80% Closed
• Application: Natural gas or propane forced-air furnaces
• Material: Coated steel, high-temperature rated