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How Do I Tell How Old My Furnace Is?

Serving Families Throughout Dallas
furnace in basement

If you're like most homeowners, you probably don't think about your furnace until it acts up or stops working. And when that happens, one of the first questions on your mind is probably "how old is this thing?" Determining the age of your furnace can be tricky, but there are a few ways to do it. Below, we will discuss a few methods for figuring out how old your furnace is.


Manufacturer's Label

One way to determine your furnace's age is by looking at the manufacturer's label. This label is typically included on newer furnaces and is often affixed to the front of the unit. It will have the date of manufacture listed on it.

Serial Number

If you can't find the manufacturer's label, or if it has been removed, you can also look for a serial number. This number is usually located on the furnace's rating plate (a label that includes information about the equipment's energy usage, manufacturer, etc.).

The rating plate can be located in any number of places depending on what make and model your furnace is, so you may need to check the front, back, sides, top, or inside of it. In some cases, the rating plate will also list the date of manufacture, so you won't need to worry about the serial number.

When you find the serial number, you will need to "decode" it. Each HVAC manufacturer arranges its serial numbers differently. For instance:

  • Lennox: Many of these systems have serial numbers with four numbers followed by one letter. The first two numbers stand for the factory where the unit was manufactured. The second two numbers are the year in which the unit was manufactured. For instance, if your unit's serial number is 1210B12345, this would mean that your unit was made in the year 2010 (12 would refer to the factory).
  • Carrier/Bryant/Payne: This manufacturer often uses a serial number that shows the week and year the unit was made. The first two digits of the serial number represent the week of the year. The second two digits represent the year. For example, a Carrier furnace with serial number 0205 was made during Week 2 of the year 2005.

If you don't know how to decode the serial number, you can search online for "how to read a [manufacturer] furnace serial number," and the result should appear towards the top of the page. You can also contact the manufacturer and provide them with the serial number, and they should be able to provide you with your unit's age.

Warranty Information

Yet another way to determine the age of your furnace is by looking at the warranty information. If you have a copy of the warranty, it will likely have the date of purchase listed on it. You can also check with the manufacturer to see if they have a record of when your furnace was purchased.

Service or Maintenance Tag

Some HVAC contractors leave a tag or a sticker on the unit stating when the equipment was last maintained or serviced. Sometimes this tag also lists the installation date, which should be close to the date of manufacture. If it doesn't, you can always try calling up the HVAC contractor who installed your system, as they should have a record of the installation and information about the equipment they installed for you.

If All Else Fails...

You can try getting in touch with your furnace's manufacturer. If you're unsure what the serial number is, you can provide them with a picture of the unit and the rating plate, and they may be able to use that information to identify your furnace and tell you its age.

At Rescue Air and Plumbing, “We’re Fast and Fair with Your Repair!” Whether your Dallas home needs heating maintenance, repairs, or a system replacement, contact us today at (972) 201-3253 for an unrivaled customer experience.