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How old is my York furnace or AC?

Type the serial number from the York label to see when it was built. York units are built by York (Johnson Controls until 2025, now Bosch), so the serials follow that company's format.

Example

W1G7123456

WPlant: W = Wichita, Kansas
1Year, first digit: 1
GMonth: G = July
7Year, second digit: 7

Built July 2017

9 years, 3 months old

Plenty of life left. Well inside the usual 15 to 25 year lifespan.

Keeping it going

Change or clean the air filter every 1 to 3 months. A clogged filter is the most common cause of strain.
Keep 2 feet of clear space around the outdoor unit and hose the fins off gently each spring.
A yearly tune-up catches small problems, like a weak capacitor, before they become a no-heat or no-cool call.
Most HVAC parts warranties run 5 to 10 years and require registration within 60 to 90 days of install. Check with the installer.

How this was read

The first letter, W, is the plant (Wichita, Kansas).
The second and fourth characters, 1 and 7, make the year: 2017.
The third character, G, is the month: July. York skips I and J in month letters.

Format: York plant, year digits and month letter. Sources: CPSC 2001 York, Luxaire and Coleman furnace recall (serials WFKM and WGKM), McGarry and Madsen: York serial numbers, Building Intelligence Center: York, Inspector Handbook: York.

Reading a York serial number

Since 2004 the year is split across the second and fourth characters, with a month letter between them. W1G7 means July 2017.

Before that the serial started with four letters. The year letters repeat every 21 years, so some codes fit two dates.

About York

Johnson Controls bought York International for about $3.2 billion, closing in December 2005.
Bosch bought Johnson Controls’ residential and light commercial HVAC business, including York, on July 31, 2025.
The 2025 sale gave Bosch US plants in Norman, Oklahoma and Wichita, Kansas.
York had bought Westinghouse’s air conditioning division in 1981, which added the Luxaire and Fraser-Johnston names.

Sources: Johnson Controls, YORK Make It Official (ACHR News), Bosch Completes Acquisition of Residential & Light Commercial HVAC Businesses from Johnson Controls (PHCPPros), York International Corp. (Reference for Business company history)

York plant, year digits and month letter

Used 2004 to today. Example: W1G7123456

The serial starts with a plant letter, a digit, a month letter and another digit. The two digits together are the year. W1G7 means July 2017: 1 and 7 make 17, and G is July. Month letters skip I and J.

Worked example: W1G7123456 was built July 2017, so it is 9 years, 3 months old as of October 2026.

Month letter (third character)
Letter	Month
A	January
B	February
C	March
D	April
E	May
F	June
G	July
H	August
K	September
L	October
M	November
N	December

Sources: CPSC 2001 York, Luxaire and Coleman furnace recall (serials WFKM and WGKM), McGarry and Madsen: York serial numbers, Building Intelligence Center: York, Inspector Handbook: York

York four letters and six digits

Used 1971 to 2004. Example: WGKM007655

The serial starts with four letters. The first is the plant, the second is the month and the third is the year. The year letters repeat every 21 years, so A to N can mean two dates. WGKM means July 2001.

Worked example: WGKM007655 fits July 1980 or July 2001. The page above explains how to tell which.

Month letter (second letter)
Letter	Month
A	January
B	February
C	March
D	April
E	May
F	June
G	July
H	August
K	September
L	October
M	November
N	December

Year letter (third letter)
Letter	Year
A	1971 or 1992
B	1972 or 1993
C	1973 or 1994
D	1974 or 1995
E	1975 or 1996
F	1976 or 1997
G	1977 or 1998
H	1978 or 1999
J	1979 or 2000
K	1980 or 2001
L	1981 or 2002
M	1982 or 2003
N	1983 or 2004
P	1984
R	1985
S	1986
T	1987
V	1988
W	1989
X	1990
Y	1991

Sources: CPSC 2001 York, Luxaire and Coleman furnace recall (serials WFKM and WGKM), McGarry and Madsen: York serial numbers, Building Intelligence Center: York, Inspector Handbook: York

York recalls

Recalls from the U.S. Consumer Product Safety Commission that name York. Whether a unit is included depends on its model and build date; the checker above flags matches.

Year	Recall	Hazard
2001	York, Luxaire and Coleman gas furnaces	Heat exchanger tubes can come loose and leak carbon monoxide.
1999	York Diamond 80 downflow furnaces	Insulation can fall onto the heat exchanger and start a fire.
1998	Plastic HTPV vent pipes on gas furnaces	Plastic vent pipes can crack or separate and leak carbon monoxide.
1996	Ducane-built oil furnaces sold under many brands	The heat exchanger can crack.

Standing at the unit? Use your phone

Point your phone’s camera at this code. The scanner opens and reads the label for you.

Same serial number format as York: Coleman, Evcon, Fraser-Johnston, Guardian, Luxaire.

Formats on this page were last checked against their sources in October 2026. York is a trademark of its owner. This page is independent and not affiliated with or endorsed by York. For warranty questions, contact York directly.

Where the serial is on a York

On a furnace or air handler, remove the front door: the rating plate is on the inside wall of the cabinet. On an outdoor unit, look on the side of the cabinet near the electrical panel.

Turn off the furnace switch before removing the front door. The outdoor unit’s plate is usually on the side panel near the electrical connections, sometimes on the back.