howoldisthat

How old is that furnace or AC?

Type the serial number from the rating plate on the furnace, air handler or outdoor unit. Each one has its own plate and its own date.

Scan insteadWhere is the label?

Example

4006A17330
  • 40Week: 40 (around October)
  • 06Year: 06 = 2006
  • APlant: A

Built Week 40 of 2006 (around October)

20 years old

In replacement window. Inside the usual 15 to 25 year lifespan, so replacement could come any time. Worth budgeting for it.

What to do now

  • Get a replacement quote now, before a breakdown in the hottest or coldest week forces a rushed choice.
  • A common rule of thumb: if the repair cost times the age in years is over 5,000, replacing usually makes more sense.
  • Ask about rebates. Many utilities and states pay toward a high-efficiency replacement.
  • Some home insurers and home buyers’ inspectors ask the age of the HVAC system. Florida 4-point inspections record it.
  • 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
  1. The first two digits, 40, are the week of the year.
  2. The next two digits, 06, are the year: 2006.
  3. The letter A is the plant that built it. The rest is a running number.

Format: Carrier week, year and plant letter. Sources: Bryant R-22 application and service manual, serial number page, Building Intelligence Center: Carrier, Building Intelligence Center: Bryant, Inspector Handbook: Carrier, Electrical Forensics: air conditioner date codes.

Good to know

Do the furnace and the outdoor unit have the same age?

Not always. They are separate units with separate serial numbers, and one is often replaced without the other. Check both plates.

Why does the brand matter so much?

Makers order the digits differently. Carrier puts the week first and ICP puts the year first, even though both are Carrier companies. The same number can mean two different dates, so pick the brand on the label.

What is R-22 and why does it matter?

R-22 is the refrigerant most AC units used before 2010. It is no longer produced in the U.S., so recharging an older system costs more each year. A build date before 2010 is a strong hint the unit uses it. The label lists the refrigerant.