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How old is my American Standard furnace?

Enter the serial number from the label. The date comes from American Standard's documented serial rules, not a guess.

Look for “Serial No.” or “S/N” on the label. Spaces and dashes are fine.

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How to read a American Standard furnace serial number

American Standard and Trane share one serial system, and part of the official evidence is American Standard’s own: a 2005 CPSC recall of American Standard gas/electric units states that the first four digits give the year, fiscal week and day of manufacture. Serials start with a year letter from 1983 to 2001, a single year digit from 2002 to 2009, and a two-digit year since 2010.

  • Year letter + week (1983–2001)

    Example: G03504353 (American Standard) was made in January 1992. From 1983 to 2001, Trane and American Standard serials start with a year letter ("G" = 1992) followed by the two-digit production week (3).

  • 1-digit year + week (2002–2009)

    Example: 91531S41F (Trane) was made in April 2009. From 2002 to 2009, the first digit is the year ("9" = 2009) and the next two are the production week (15).

  • 2-digit year + week (2010 onward)

    Example: 17103N6MF4 (Trane) was made in March 2017. Since 2010, the first two digits are the year (2017) and the next two are the production week (10).

Not decoded yet: Pre-1983 Trane and American Standard formats are not decoded. Many plates print a MFR DATE, which is authoritative.

Where to find the serial number

Turn the furnace off at its switch, then remove the upper access door (the burner or blower compartment). The rating plate is on the inside wall of the cabinet or on the back of the door.

The plate lists the model number and serial number; many newer plates also print a date of manufacture.

American Standard furnace model numbers

If the brand name isn't visible on the label, the model number can help. Model numbers like these follow American Standard's published nomenclature:

How long does a furnace last?

A typical furnace lasts about 15–20 years. That's a general estimate: maintenance, usage, climate and installation all matter, and age alone doesn't tell you a unit's condition.

Range from NAHB / Bank of America, Study of Life Expectancy of Home Components (2007, archived copy), Carrier: how long does a furnace last? and Lennox: how long does a furnace last?.

American Standard furnace recalls

From the U.S. Consumer Product Safety Commission, checked 2026-09-29. A decoded result checks your model number against recalls live.

Questions

How can I tell an American Standard model number from a Trane one?
American Standard’s charts put an A in the second position of outdoor units (4A7A6…, 4A6V…) and start furnaces with AU or AD, while Trane furnaces start with TU or TD. Other models, such as S-series furnaces and TEM or TAM air handlers, are sold under both names, and American Standard’s own chart also allows T, so a 4TT… number doesn’t prove the unit is a Trane.
Does my American Standard plate show the date?
Often. Trane and American Standard plates frequently print a MFR DATE, and when it’s there it’s the most reliable date. An American Standard plate with serial G03504353, for example, reads MFRD. 01/92, which matches the serial’s year letter G (1992) and week 03.
Why is the month only approximate?
The serial gives a production week, not a date. The 2005 recall calls it a fiscal week and a Trane decoder calls it a calendar week, but neither says exactly how the weeks line up with dates, so we show the week and an approximate month.
How can I tell how old my American Standard furnace is?
Find the serial number on the rating plate and enter it above. American Standard furnaces use the Trane family serial format, which includes the manufacture date. For example, G03504353 was made in January 1992: From 1983 to 2001, Trane and American Standard serials start with a year letter ("G" = 1992) followed by the two-digit production week (3).
Where is the serial number on a American Standard furnace?
Turn the furnace off at its switch, then remove the upper access door (the burner or blower compartment). The rating plate is on the inside wall of the cabinet or on the back of the door. The plate lists the model number and serial number; many newer plates also print a date of manufacture.
How long does a furnace usually last?
A typical service life is about 15–20 years. That's a general estimate: maintenance, usage, climate and installation all matter, and age alone doesn't tell you a unit's condition.
Do Trane furnaces use the same serial format?
Yes. American Standard and Trane use the same serial-number conventions (Trane family), so the same decoding rules apply.
How reliable is the result?
The Trane family rules come from documented sources, but they're in Beta while we check more real-world examples, so results are capped at medium confidence. If a serial doesn't match a documented format, we say so instead of guessing.

Same serial format: Trane furnace

Other American Standard equipment: air conditioner, heat pump

Sources

Rules last reviewed 2026-09-28. These rules are in Beta while we verify more real-world examples, so results are capped at medium confidence.

Manufacture dates are decoded from manufacturer serial-number conventions and available documentation. Serial formats can change. Verify critical equipment information with the manufacturer when necessary.