How Old Is My Lennox Air Conditioner?

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There are many reasons why you may need to know the age of your Lennox air conditioner, whether to know if it is nearing the end of its lifespan or to determine avenues of reparation. Figuring out the year of manufacturing, however, may not be as simple as you expected. So how can you find out the age of your Lennox air conditioner? We've done the research to give you an answer.

To find out the age of your Lennox air conditioner, you should follow these three steps:

  1. Locate the serial number on your Lennox HVAC system.
  2. Determine the style of the serial number.
  3. Decipher the manufacturing date from the serial number.

So now you know the basic steps for figuring out your Lennox air conditioner's age. However, you may need more instructions, because it's not as straightforward as it seems. In this post, we'll discuss the topic in greater detail. Keep reading to learn more.

Air conditioner unit outdoors in side yard of a brick home in hot summer season, How Old Is My Lennox Air Conditioner?

How Do You Read A Lennox Date Code?

Lennox Corporation trademark logo and trademark.

A Lennox air conditioner can be aged by looking at the serial number, but you have to know where to locate it and how to read it. Here, we'll give you the steps to follow.

1. Locate Serial Number

All Lennox air conditioner units are given a unique serial number. To make it easier for owners and HVAC technicians to access all of the information that may be needed for the unit, all of it has been printed on an "identification plate."

To find the serial number, you must first find the identification plate. This will be on the outside casing of the unit. Typically, it will be white with black type.

There will most likely be several numbers on the identification plate. The serial number will be the series of numbers, or numbers and letters, that follow the word "serial" or "S/N."  Now that you know where to find the serial number, it's time to talk about determining the style of this number.

2. Style Of Serial Number

The style of the serial number will determine how the date of manufacturing is listed. There are four styles.

Style 1 consists of ten digits. The first four digits are numerical. The fifth digit is a letter. The following five digits are also numerical. An example of a style 1 serial number is 1808B13467.

Style 2 consists of nine digits. The first digit is a letter. The following five digits are numbers. The last three digits are numbers. An example of a style 2 serial number is D44325AA678.

Style 3 consists of ten digits. The first two digits are numerical. The third digit is a letter. The following two digits are numerical. There is then a space followed by one more letter and four numerical digits. An example of a style 3 serial number is 12B56 J7898.

Style 4 consists of ten digits. All are numerical. An example of a style 4 serial number would be 3214560650.

Now you should know which style serial number your unit matches. From here, you should be able to decipher the manufacturing date.

3. Decipher Manufacturing Date

When you have a style 1 serial number, you can find out the manufacturing date based on the third and fourth numerical digit and the fifth letter digit. The numerical digits indicate the year, and the letter digit indicates the month.

Using our example for a style 1 serial number 1808B13467, we can see that the year of manufacturing would be 2008. The month of manufacturing would be February.

When you have a style 2 serial number, you can find out the manufacturing date based on the seventh and eighth digits, both letters. The letters will range A-M for months, and A-N for years 1980-1992. The first of these digits represent the month, and the second of these digits represent the year.

So, using our example for a style 2 serial number D44325AA678, we can see that the month of manufacturing would be January and the year of manufacturing would be 1980.

If you have a style 3 serial number, you can find out the manufacturing date based on the first five digits of the serial number. The first two digits, both numerical, represent the day. The third digit, a letter, represents the month. The fourth and fifth numerical digits represent the year.

Using our example of a style 3 serial number 12B56 J7898, we can see that the day of manufacturing is 12. The month of manufacturing is February. The number "56" must be flipped, and from this, the year of manufacturing can be determined to be 1965.

With a style 4 serial number, the manufacturing date can be found in the last four digits, all numerical. The seventh and eighth digits represent the year. The ninth and tenth digits represent the week.

Using the example of a style 4 serial number 3214560650, we can see that the year of manufacturing is 2006, and the week of manufacturing is the 50th of the year.

Lennox HVAC System Lifespan

Now that you've been able to determine when your Lennox air conditioner was manufactured, you may want to know more about the expected lifespan of this system and how you can extend it. We'll give you more direction here.

How Long Do Lennox Air Conditioner Units Last?

Lennox air conditioners are expected to last 15-20 years with reasonable care. With pristine care and maintenance, they could last even longer.

The Lennox company is a trusted provider of heating and cooling systems. These HVAC units are created to provide steady, dependable comfort and last with few repairs and little cost to the owner.

How Often Should Lennox Air Conditioner Units Be Serviced?

Horizontal shot of four air conditioning units outside of an upscale apartment complex.

These air conditioner units should be serviced once per year by an HVAC professional. It's a good idea to have this done in winter or early spring. It could save you money and discomfort by preventing your air conditioner from malfunctioning in the heat of summer.

Maintenance To Extend Lifespan

There are also a few things that you, as the owner and user of the Lennox air conditioner, can do to maintain it and keep it running smoothly for a long time to come.

First, you should replace or clean your air filter at least once per month. If it seems that the conditions surrounding your home are particularly dusty or if your ventilation system needs a cleaning, you may need to do so more frequently.

Check out these Lennox air filters on Amazon.

You can also routinely clean the air conditioner's coils. Of course, this is something that will be done at your annual servicing, but it's a good idea to check the coils and clean them yourself periodically if you can. This will prevent any malfunction with this facet of your air conditioner.

You should keep debris from crowding the air conditioner unit as well, removing anything that has made its way to the unit. This could be shrubs, tree limbs, leaves, and undergrowth. You could also cover the unit to prevent wear from surrounding elements.

Take a look at this air conditioner cover on Amazon.

Another easy maintenance task is making sure the coils and fins on the air conditioning unit stay straight. This is something you should routinely check, as these are a bit fragile and often bend.

Frequently Asked Questions

Latin descent, blue collar air conditioner repairman working at residential home.

We've given you instructions on how to determine the age of your air conditioning unit as well as described the easiest ways to maintain your Lennox HVAC system for the longest lifespan. Now we'll cover some of the most frequently asked questions about Lennox air conditioners.

What Do Lennox Model Numbers Mean?

Model numbers are not the same as serial numbers. While serial numbers are unique to each unit, the model numbers are specific to the model of the unit. So, all of the units that are the same model should also have the same model number.

Model numbers are important to the Lennox company, as they signify the age, size, and warranty information for the HVAC unit. They are helpful to both the owner of the unit and the HVAC technician, as they will help determine which parts are appropriate for repairing a unit.

What Is The SEER Rating On A Lennox Air Conditioner?

Lennox air conditioners decidedly have some of the highest SEER (Seasonal Energy Efficiency Ratio) ratings of HVAC systems on the market, but they are not all created equal.

On the low side, the Lennox 16ACX model has a SEER rating of 14-17. Still, this is average in comparison to other HVAC systems. On the high side, the Lennox XC25 model has a SEER rating of 26. Most Lennox air conditioning models fall somewhere between these two values.

In Closing

A view of an air conditioner condenser unit in the backyard of a home.

Determining the age of your Lennox air conditioning unit may have proved to be a bit more complicated than you expected, so we've given you instructions.

We described how to locate your unit's serial number, determine the style of the serial number, and from there, decipher the manufacturing date of the air conditioner. We hope this has given you some direction and know-how moving forward.

Want to learn more about Lennox HVAC systems? Visit these related posts:

How To Add Freon To A Lennox Air Conditioner

How To Reset Lennox Air Conditioner

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