Using the wrong size air filter can lead to poorer air quality, higher energy bills, and potential damage to your HVAC system.
Dust Accumulation in Ducts: An improperly sized filter can allow dust and debris to bypass the filter and enter the ductwork. This accumulation can lead to dirty ducts, which can not only reduce air quality but also promote the growth of mold and bacteria, causing further health concerns.
Standard air filters have pre-defined nominal sizes for compatibility with most HVAC systems. Custom-made filters fit non-standard dimensions. The Nominal filter size for a custom filter may still round to convenient measurements, but its actual size matches the dimensions of the HVAC system or filter slot.
The most common problem you will face with a backwards facing filter is simple inefficiency. If your furnace is forced to blow air through the non-porous end of a filter, it will take more energy to do so. The blower will be overworked and you will pay more money for your heating.
Air Filter Problems with Poor Fit
If you purchase a filter that's too large, it won't slide into the slot correctly. If the filter is too small, it won't cover the entire space and may allow dust and dirt to flow past.
The blower fan in your HVAC system may not be able to handle anything stronger than MERV 12. A filter that blocks airflow will raise the air pressure in the HVAC ventilation system, which can damage ducts and even the AC and heater.
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.
If you let it run very long without filtration, contaminants will build up. IAQ plummets when there is no filtration. Your family may experience health problems as contaminants and dust move through ductwork into the home. Mold spores could proliferate in the ducts, causing breathing issues.
The direction of airflow in the HVAC system can cause some confusion, and for good reason too! To ensure your furnace filter is put in the correct way, make sure the arrow on the furnace filter is pointing towards the furnace.
There are Different Filter Sizes
You cannot buy just any furnace filter and expect it to fit. You will need a furnace of a specific length, width, and height in order to replace your current filter. The simplest way to do this is to look at the current filter you have and match the new ones to it.
Gaps around the edges of a too-small filter will allow unfiltered air into your HVAC system, negating the filter's purpose.
What Is the Most Common Size of Air Filter for a House? The most common size air filter for a house is usually 20 x 20 x 1, but this can vary depending on the specific HVAC system installed.
Home size, room size and HVAC slot size will impact the amount and type of filters you'll need. It may sound strange, but size has many implications for air filters. The size of your home, size of individual rooms and size of your HVAC filter slot can all come into play when it comes time to buy new air filters.
Air filters remove impurities from the air, but when installed incorrectly, the contaminants will not get trapped in the filter and remain in the air. Placing the filter the wrong way will also cause it to clog, which means the indoor air quality will be reduced.
If the air filter is too large, it will cause the system to run slowly and reduce the efficiency of the filtration process. This requires more energy to run during the day and will increase your bills.
Installing an air filter backward can damage your furnace or HVAC system, as the airflow will be decreased dramatically. A backwards filter prevents air from flowing into the furnace, which prevents air from flowing out of the furnace.
What if there is no arrow on the air filter? If there's no arrow on your air filter, just make sure the side with the frame (usually the cardboard or metal side) faces the furnace. The flat side of the filter should face the return air duct.
NO. A furnace filter has a critical job to perform and a filter cannot be run without one. For a furnace to work properly, it should always be equipped with a clean, working filter. As we'll see, a dirty filter can cause problems, and so can having no filter at all.
On the new filter, find the arrow indicating the proper airflow direction. The arrow must face toward the furnace and away from the return duct that pulls the air in need of heating or cooling.
It will operate without one, but you'll risk potential damage to your system and to your health and the health of your family, and that's just not worth it. One of the primary functions of the air filter on your furnace is to keep dust and other airborne particles from collecting on your furnace's inner components.
Check your furnace and AC for individual filter slots to ensure you buy the correct size for each (if applicable). Using the wrong size filter reduces efficiency, air quality, and can even damage your HVAC system.
You cannot use a 20x25x4 filter in place of a 20x25x5 filter because the thickness is different. The 20x25x5 filter is designed for specific systems that require extra thickness for proper airflow and filtration. Always use the filter size recommended by your HVAC system's manufacturer to ensure optimal performance.
Stiffer builds for steadfast seal: 1-inch filters have less material to control, which means the frames are thinner. Thin frames have flimsy seals which let through unfiltered air, defeating the purpose of your filter. 5-inch frames are thicker and fit into the furnace more seamlessly.