Usually they round up or down to the nearest inch, so it is less likely that these two filters will fit the same furnace because of the rounding. However, if your filter is close to 20x25x4. 5, and the actual dimensions of the 20x25x5 filter are closer to 20x25x4. 5, than they might fit.
Going down in thickness by an inch shouldn't be a big deal - for example, you should be able to use a 4-inch filter instead of a 5-inch filter. If you are considering a thicker air filter in order to improve air quality it may be better to focus on the MERV rating.
actual size of an air filter can affect filter compatibility if it doesn't fit properly into the HVAC system filter slot. Ensuring the actual size aligns with your HVAC system's requirements, even when the nominal size matches, is important if you want system efficiency, proper filtration, and the best performance.
Actual Size 19 5/8" x 24 3/16" x 4 15/16." Case of 2.
Using the wrong size filter reduces efficiency, air quality, and can even damage your HVAC system. You can learn more about the difference between furnace and AC filter sizes here.
UNDERSTANDING FILTER SIZES
Therefore, for example, a 16x25x4 filter is 16 inches long, 25 inches wide, and 4 inches thick. It's important to note that filters with different dimensions are not interchangeable due to variations in frame size and media area.
This extra depth gives the filter more room for airflow. That means that as the filter collects dirt and other debris from your air, it won't restrict the airflow in your furnace as much. This prevents damage to the furnace and gives the filter itself a longer lifespan.
How often do homeowners need to change their air filters to receive all the benefits? It really depends on the home and personal preferences. However, as a rule of thumb, because 20x25x5 air filters are stronger than most air filters, most homeowners only use two to three 20x25x5 air filters a year.
The abbreviation stands for Minimum Effective Reporting Value. In other words, it's a measurement showing how small the holes are in the filter. The higher the MERV number, the smaller the holes, and the less that can pass through. Ultimately, this is what makes MERV 14 filters not a good choice for home use.
Not all 20x25x5 air filters are alike. They differ in material, MERV rating, and effectiveness, affecting performance and HVAC compatibility.
If the filter is missing or unmarked, measure the filter slot in your HVAC system for these dimensions. Always ensure the size matches exactly, as even slight differences can affect filtration efficiency and system performance.
A good MERV (Minimum Efficiency Reporting Value) rating for residential HVAC systems is typically between 8 and 13. MERV 8 filters capture basic particles like dust, pollen, and pet dander and are adequate for most households.
Currently, the most common size furnace filters are: 20 x 20 x 1. 16 x 25 x 1. 20 x 25 x 1.
Usually they round up or down to the nearest inch, so it is less likely that these two filters will fit the same furnace because of the rounding. However, if your filter is close to 20x25x4. 5, and the actual dimensions of the 20x25x5 filter are closer to 20x25x4. 5, than they might fit.
If you're switching to a different air filter manufacturer, it's best to use the actual size of your current filter when searching for a replacement. While nominal sizes are standardized, the actual sizes can vary slightly between manufacturers.
Fortunately, most 20x25x4 air filters last between six to eight months. By that calculation, the average homeowners will not need more than two 20x25x4 air filters in any given year. In contrast, a one-inch air filter will need to be changed every two to three months.
In most cases, a MERV 11 air filter isn't too high for residential use. Generally speaking, anything under a MERV 13 air filter should provide very efficient air purification in a home without impacting airflow.
How Often Do I Need to Change Out My Air Filter? Generally, most air filter manufacturers and HVAC companies recommend changing your air filter every 90 days, or 3 months. That can change based on where your home is located (ex. dusty, dry climates), if you have any pets, and the age of your system and equipment.
The MERV 11 air filter is the wrong choice for people who do not own pets and do not have any breathing trouble; this is because it can lead to restricted airflow. Air filters with higher ratings can also have negative effects on HVAC components.
For 1- to 2-inch filters, replace them every 1 to 3 months. For 3- to 4-inch filters, replace them every 6 to 9 months. For 5- to 6-inch filters, replace them every 9 to 12 months.
This leads to a variety of issues for your HVAC system including system inefficiency, higher energy bills, inadequate air quality, and ultimately failure. If you haven't been swapping your air filters as frequently as you should, there's no time like the present to start practicing this crucial maintenance step.
Not every filter can be reused; HEPA filters and soft, pleated filters usually cannot be reused based on their design. If the material is made with something like fiberglass, it is pointless to reuse the filter, because of how it traps particles. The truth is, the more powerful air filters are usually disposable ones.
High-MERV filters increase the static pressure of your system, and if the ductwork is already marginal, this can cause the airflow to drop to a level where the temperature exceeds the furnace's limit.
Damage to the HVAC System
Reduced Efficiency of the System: An improperly sized air filter can create an imbalance in the airflow, which means the system may not operate at its designed efficiency. When the HVAC unit is forced to work harder, it consumes more energy, leading to increased utility bills.
Pleated filters can restrict airflow slightly more than non-pleated ones, but they balance filtration and airflow. Choosing the right MERV rating (between 8 and 13) ensures your system gets proper airflow while still effectively filtering the air.