With all the different air filter sizes available, it can be daunting to find the right one for your AC unit. There are thousands of air filter sizes, and HVAC manufacturers are incentivized to make it as tricky as possible so that you are stuck paying for their overpriced replacements.
You can find more information on our web, so please take a look.
Don&#;t worry, though - we&#;ve got you covered. This guide will take you through the process of identifying your air conditioner filter size step-by-step, so you can buy a properly sized replacement air filter without any hesitation.
Most filters come labeled with two-size measurements that can be found along the filter&#;s side. Often there is a &#;nominal&#; size written in big print, as well as an adjacent &#;actual&#; size written in smaller print. All of the filters listed on filterbuy.com are listed by nominal size unless specifically labeled otherwise.
This is the easiest and most obvious way to find your AC filter size, but not all filters have size measurements listed on them. In this case, finding the size of your filter will require taking a few measurements by hand.
A lot of our customers can sometimes get confused by the difference between nominal vs. actual sizes listed on replacement air filters.
The size listed in large print on the size of your filter is generally the &#;nominal&#; filter size. We do our best to specify actual dimensions throughout our website so that there is no confusion, however, filters within .25&#; or less of your existing filter are generally interchangeable.
If the size is not written on the side of your air filter, the next step is to take out your trusty tape measure.
You need to measure the length, width, and depth.
For air filters, the length and width dimensions are interchangeable, though conventionally the larger of the measurements is the width and the shorter of the measurements is the length. The smallest of the dimensions will almost always be the depth.
For example, if an air filter&#;s dimensions are 12&#; X 20&#; X 1&#;, that means the following:
In some cases the length and the width are interchangeable, but you&#;ll always need to make sure that you measure for those 3 specific air filter or furnace filter dimensions.
Below you can see an example of an air filter size chart:
As for the depth measurement, standard air filter sizes are nominally 1&#; (actual 0.75&#;), 2&#; (actual 1.75&#;), and 4&#; (actual 3.75&#;) deep. These standard air filter sizes are easier to find and are the most commonly used. To shop for these standard filters by size, click below.
If you don&#;t see your size, you can create it yourself using our custom filter tool. Building a custom AC or furnace filter allows you to pick specific dimensions if the standard sizes don&#;t work for you.
Whether you decide on custom or standard, we always provide the ability to select the performance rating of the filter, pick the number of filters, and choose whether you would like filters delivered at recurring intervals.
If the filter you are looking for does not match these standard measurements, then you can look for your brand on our whole house replacement filters page or request a custom-size filter!
Once you properly measure your air filter and get the right dimensions, you can search for it on our common filter sizes page. We recommend you start your replacement air filter search by narrowing it down to your air filter&#;s depth.
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.
The size of the filter is calculated by measuring its length, width, and depth. Always measure from edge to edge. Remember to write down the measurements in the same order: length, width, and depth.
Air filtration is measured in MERV (Minimum Efficiency Reporting Values), a standard that rates the overall effectiveness of air filters. The higher the MERV rating, the finer the filtration and the more particles it can filter out.
To know what size air filter your car needs, consult the vehicle's owner's manual. If it's not stated there, you can remove the existing air filter and measure it. It's important to get the right size to ensure optimal performance and protection for your engine.
Normal air filter sizes vary depending on the system they are intended for. In general, standard sizes for home HVAC systems range from 10" x 20" to 25" x 25" and depth can range from 1" to 6".
A standard air filter size for home HVAC systems is often 20" x 20" x 1". However, the size can vary greatly depending on the specific system. Always measure your existing filter or check your system manual to ensure you get the right size.
To measure the air filter on an AC unit, remove the filter and measure its length, width, and depth. Always measure from edge to edge and round up to the nearest inch if necessary.
It's recommended to change your air filter every 60 to 90 days. However, if you have pets or allergies, you might need to change it more frequently, possibly every 30 days.
Yes, you need the exact size air filter. Using the wrong size can lead to inefficiency and potential damage to the system as it may allow unfiltered air to pass through.
Using the wrong size air filter is not advised. It can lead to decreased efficiency, increased energy costs, and potential damage to the system as unfiltered air is allowed to pass through.
When choosing an engine air filter, consider the vehicle's make, model, and year to ensure compatibility. Also, consider the MERV rating for the filter's effectiveness in removing particles and pollutants.
No, car air filters are not a standard size. The size varies depending on the make, model, and year of the vehicle. Always refer to your vehicle's owner's manual or measure the existing filter to determine the correct size.
For more information, please visit Xuhaifa Filter.
Volumetric Efficiency &#; Calculate your engine&#;s VE (Volumetric Efficiency Here)
For a normally aspirated engine making 60bhp per litre use a figure of 70
For a normally aspirated engine make 100bhp/litre use a figure of 90
Turbo cars with 1 bar boost pressure, use a figure of 200
Turbo cars with 2 bar boost pressure, use a figure of 300
Using K&Ns recommendations from this page, for airflow of 12,000 litres per minute, the recommend filter area is 596 sq/cm
Bring those figures down to something more usable.
For litres per minute of airflow, filter area should be a minimum of 50 sq/cm
An air filter can never be too big, so lets aim for a figure of 100 sq/cm per litre/min of air flow.
The bigger the air filter, the better it filters the air and the less it needs to be cleaned. We are also adding some area to account for the area around the flanges and also to account for the use of different materials ie foam & paper.
We are also adding some headroom. We are also taking into consideration the performance of the air filter when it has been used for sometime ie when it has absorbed dust and is not flowing as much air as it did when it was new.
Finding the CONE air filter
So the next formula allows you to calculate the surface area of a filter when we knows its height, its base diameter and its top diameter. This is for round cone filters.
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If you are using a panel filter you can use this formula
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A vacuum gauge can help identify a filter that is too small.
Note the position of the vacuum gauge needle when the engine is switched off.
When you are at high/maximum RPM and full throttle, you want to see the needle in the exact same position.
If the needle is in the same position, it shows your intake system is not a restriction.
And if the needle is not in the same position&#;.. to state the obvious, there is a restriction.
The most obvious and easy way is to remove the air filter housing and see if it cures the problem.
if not, check if the air filter has a bell mount at the base, if not get a filter with a bell mouth, companies like AEM have bell mouths in all of their filters.
If using a bell mouth filter of the correct size still does not cure the problem then you need to start looking at the intake piping itself. Does it have sharp corners, are the hoses compressing under full throttle, what is the inside of the hose like (smooth/rough), can you shorten the intake path, is the filter able to pull in sufficient air (ie is the filter jammed up against the side of the engine bay)
In a perfect world you want a direct run into the intake manifold from the engine but for packaging purposes this may be impossible.
On cars with MAP sensor, you may also be limited in what you can do with the intake piping. To make an engine idle properly, the volume in the intake after the MAF sensor needs to be limited. If there is too much air volume after the MAF sensor, the air may not move smoothly across the MAF sensor causing idling problems.
In short, you need to be careful changing the intake pipework after the MAF sensor.
Convert Area
Convert Volume
Engine Equations
Air Flow Calculation
For more information, please visit Wholesale Engine Air Filter.