How to find carrier AC filter size?

Author: Sidney Kautzer  |  Last update: Saturday, June 27, 2026

Assuming your existing filter is sized correctly, look to see if the dimensions of height, width, and depth are printed on its frame. Look for the model number on your existing filter's frame. Look at the manual for your indoor unit and see if it lists the correct air filter dimensions.

How to find carrier filter size?

To determine the size of your current filter, look for the sizing information printed on the side of the filter. Once you have determined the size of your current air filter, there are various options to buy replacement filters, including: Contact your local Carrier expert (dealer).

How do I know the size of my AC filter?

To determine your air filter size, you need to measure its length, width, and depth. These measurements are usually printed on the side of the filter. If not, you can use a tape measure to get the dimensions.

How do you tell what size my carrier AC unit is?

Find your condensing unit and search for a data plaque or sticker on the side. You should see a model number and a string of numerals and letters. There should also be an even, two-digit number – which indicates the AC tonnage of the unit. This number is typically between 18 and 60.

Where do I find filter size?

The easiest way to find out what size filter to get for your furnace is to simply remove your current filter and look at its dimensions. These are typically printed along with one of the sides of your filter.

How to find your Air Conditioner/Furnace Filter

What is the symbol for filter size?

Technically, the ⌀ symbol is standard drafting notation for "diameter". But yes, on a lens that symbol will always represent the required filter size (filters are sized based on the diameter of their screw-on connection).

How do I find my AC carrier model?

You should be able to see the model number on a rating-plate or decal right on the front of a ventilator or an evaporator coil and on the side if you have a fan coil.

Where can I find the size of my AC unit?

Finding the tonnage of your AC unit may be as simple as walking outside and reading the label on the condenser unit. Most of the time, manufacturers don't list tons, though; they list BTUs instead. Lucky for you, we already taught you that math! Simply divide the BTUs by 12,000 to calculate the tonnage of your unit.

How to read carrier serial numbers?

Carrier/Payne/Bryant

Carrier systems made in the last 20 years or so encode the week and year of manufacture within the first 4 digits. The first 2 are the week of the year (1-52) and the second are the year. For example 0199 would mean the system was made the first week of January in 1999.

How do I find my AC filter?

Air filters are commonly located between the return duct and the air handler. If you still have not found your air filter or furnace filter, look between the return duct and the air handler. The air handler is a large metal box that houses the fan and its motor.

Are AC filters standard size?

What Are the Different Sizes of Air Filters? Air filters come in a variety of sizes, with some of the common ones being 10 x 20, 14 x 20, 16 x 24, 18 x 30, 20 x 30, and 24 x 24. These measurements are in inches and represent the length, width, and sometimes the thickness of the filter.

How do you calculate filter size?

The recommended minimum filter surface area is 2.50 cubic feet per minute (cfm) per square inch of filter area. Example 1: 2000 cfm ÷ 250 inches = 800 square inches or 20" X 40" filter grill. The maximum allowable filter velocity is 300 feet per minute (fpm) on disposable filters.

How to check air conditioner filter size?

Look at Your Existing Air Filter

If your HVAC system has an air filter, you can look for its size to ensure you can get the right replacement. Most filters have sizes listed on the side in print, including the length, width, and depth in inches. Usually, they're listed in that order.

How often do you change the filter in a carrier air conditioner?

Some should be replaced every 30 to 60 days. Others might last 6 months to a year. The answer depends on factors such as how often you use the system, the type of filter, whether there are any pets in the home, and your personal habits such as having smokers in the house, use of a wood-burning fireplace, and more.

How do I choose a filter size?

Usually, you can find the diameter by looking for the geometric symbol on the body of the lens - “ø”. The number next to that is the one you need. If you can't find it on your lens though, just take a look at your user manual or the manufacturer's site, and it should be pretty easy to find.

How do you tell your AC size?

Simply divide the BTUs by 12,000 to calculate the tonnage of your unit. For example, if your air conditioner is 36,000 BTUs, you have a 3-ton unit. Some manufacturers bury tonnage or BTU information in their model numbers. Look for an even, two-digit number between 18 and 60.

Can I install a different brand of AC indoor and outdoor unit?

In the worst circumstance, the incompatible system may not function at all. Or, it may seem to operate initially and then break down after some time. In all circumstances, the machine's efficiency and longevity will be compromised.

How do I know the BTU of my air conditioner?

An air conditioner's model number is a string of numbers and letters. Within the string, you should see an even, two-digit number. Add three zeroes to the number and you have the BTU rating. Divide the two-digit number by 12, and you have the tonnage.

How to tell the size of a Carrier AC unit?

Finding your Carrier AC's tonnage is easy! Check the nameplate on the outdoor condenser unit. It'll have a model number and a string of numbers/letters. Look for a two-digit number - that's your tonnage!

Which brand is Carrier AC?

Carrier Corporation was acquired by United Technologies Corporation (UTC) in July 1979. Prior to the acquisition by UTC, Carrier Corporation was known as the Carrier Air Conditioning Company. International Comfort Products (ICP), headquartered in Lewisburg, Tennessee, was acquired by Carrier in 1999.

What size filter do I have?

Check the label, which should be on the side of your filter. The listed dimensions are your filter's nominal size. If the filter fits properly, order a filter with the same nominal size from any manufacturer. If your current filter isn't labeled, take manual measurements.

What are standard AC filter sizes?

Most Common Furnace and AC Filter Sizes
  • 10 X 20 X 1''
  • 14 X 20 X 1''
  • 16 X 24 X 1''
  • 18 X 30 X 1”
  • 20 x 20 x 1.
  • 16 x 25 x 1.
  • 20 x 25 x 1.
  • 20 x 25 x 4.

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