Lennox Furnace Manufacture Date

How to Determine the Manufacture Date of a Lennox Furnace

Knowing the manufacture date of a Lennox furnace is essential for homeowners, HVAC technicians, and buyers. It helps in assessing the unit’s age, evaluating warranty status, scheduling maintenance, or planning for replacement. Lennox furnaces come with unique serial numbers that contain the key to identifying their production date. This article dives deep into the methods used to decode these numbers and highlights why this information is crucial for proper furnace management.

Understanding Lennox Furnace Serial Numbers

Each Lennox furnace has a serial number typically found on the unit’s rating plate or inside the furnace cabinet. This serial number encodes manufacturing date details, although the format has varied over the years. For Lennox furnaces, the serial number usually consists of letters and numbers where certain digits correspond to the week and year of production.

Location of Serial Number

• On the furnace rating plate, usually on the blower compartment or furnace door edge
• Stamped on the furnace cabinet
• Inside the service panel or near the burner assembly

Decoding Lennox Furnace Manufacture Date from Serial Numbers

Lennox has primarily used two common serial number formats for furnaces:

Format 1: Older Lennox Furnaces

Older models typically encode the month and year manufacture in the first four digits of the serial number.

• First two digits = Year (last two digits of the year, e.g., “21” for 2021)
• Next two digits = Week of the year (01 to 52)

For example, a serial number starting with “2150” indicates the furnace was made in the 50th week of 2021.

Format 2: Newer Lennox Furnaces (Post-2000s)

For newer furnaces, Lennox uses a date code that sometimes appears after the initial letters in the serial number:

• Two letters followed by six digits
• Digits typically include the week and year within the six-digit string
• The third and fourth digits after the letters usually represent the week
• Fifth and sixth digits represent the year

For example, a serial number “AB12352145” suggests the furnace was manufactured in the 35th week of 2021.

Using Model Numbers as a Reference

While serial numbers provide the precise furnace production date, model numbers are useful for narrowing down the manufacturing time frame. Lennox model numbers indicate the series, type, and efficiency rating, which change over time with updated models.

• Older models often lack a specific year in the model number, but general model history helps estimate manufacture era
• Newer model numbers may include year designations or series that align with manufacturing year

Why Knowing the Manufacture Date Matters

Identifying the manufacture date of a Lennox furnace benefits several important areas:

• Warranty Verification: Fender warranties typically range from 10 to 20 years. Checking the manufacture date confirms warranty eligibility.
• Maintenance Scheduling: Older units may require more frequent inspections and part replacements.
• Resale Value: Used furnace buyers want to know the exact age of units before purchase.
• Replacement Planning: Knowing furnace age helps homeowners decide when it’s time to replace the unit with a newer, more efficient model.

Additional Tips for Lennox Furnace Owners

• Keep Serial Number Records: Document the serial and model numbers for service and warranty ease.
• Consult Lennox Support: For unclear serial numbers or verification, contact Lennox customer support or a certified HVAC technician.
• Schedule Expert Inspection: Regular professional furnace checkups ensure safety, reliability, and efficiency.

Summary Table: Decoding Lennox Furnace Serial Numbers