It is an acronym for "high efficiency particulate air [filter]" (as officially defined by the U.S. Dept. A MERV 8 filter can remove particles down to 3 microns in size at an efficiency of 70 percent or greater (1 micron is about 0.04 thousandths of an inch). Below is a chart comparing the pressure drop of standard 20X24X1 MERV8, 11, and 13 at 1000 CFM. If the house was comfy all over, but you upgraded your filter and now rooms distant from the furnace or air handler arent getting enough warm or cooled air, low airflow caused by a restrictive filter should be considered. An air filters minimum efficiency reporting value (MERV) rating measures how effectively the filter stops dust and other contaminants from passing through the filter and into the air stream. Most of them will specify using a certain size filter, and they may also suggest a minimum MERV and a maximum MERV or IR (resistance to air flow of a new filter). The furnace filter frames use a M 10 rated level air filter. The filters initial pressure drop (initial resistance) will vary by the filter type, MERV rating, and size. Camfil makes the best filters on the market: they are the most energy-efficient, have a longer and more effective service life than other filters, and feature a lower pressure drop than competing brands. 99.97% or better for all particle sizes). Even filters sharing the same MERV rating may have differing pressure drops. Remembering to change your air filter is key to reducing the risk from pressure drop. These particles could hurt health and productivity. Does the airflow significantly improve? Once the filter is fully loaded the filter will reach its final pressure drop. LakeAir provides discounts to Veterans, First Responders, and the Elderly. Depending on what size of particles the air filters can trap or let through, they are classified in a chart known as the MERV rating. ; High-rated media is able to retain fumes . Thick and high-MERV filters can cause a significant drop in pressure inside your HVAC system from before to after the filter. What are the benefits of a higher MERV rating? Get more great content like this sent to your inbox. Woodhead Publishing, 2017. Hi Diane, MERV 20 are highly specialized filters and are not sold online. They are usually reserved for superior commercial applications. LakeAirElectrostatic Air Filterswork as well as a MERV 16 air filter. of Energy). It also shows air filter efficiency levels. MERV Ratings 17-20 reflect values that are used in the rating of HEPA and ULPA filters. When your HVAC system is running the filter slows and limits the air that is being pulled through your vents and ducts. We are hiring! For example, a household pleated filter that uses synthetic media will have a lower pressure drop than a micro-fiberglass media that is used in critical environments such as a hospitals and datacenters." Remembering to change your air filter is key to reducing the risk from pressure drop." The resulting rating is theen given to each filter. 1.0-3.0 greater than or equal to 90% The higher the pressure drop the more restrictive the filter is to air flow. This often coincides with a higher MERV rating; however, this also means that the filter is slightly more restrictive and the airflow rate through the filter is lower. These filters should not be used in home HVAC or furnace systems. 3.0-10.0 greater than or equal to 70%, 1.0-3.0 greater than or equal to 50% A filters material type and efficiency rating affect the pressure drop and resistance to air flow. "text": "Static pressure is the measurement of the exertion of air flow your HVAC system is moving throughout the system and ductwork." About Us | Contact Us | Privacy Policy| Cookie Policy| Terms of Use| Do Not Sell My Info. In some ways they are better than all media filters in others they have drawbacks. Filters with a (M) value 5 through 8 remove finer dust particles. They also found that air flow in the high-MERV filters dropped by 7% and 11% in the two HVAC systems compared to the low-MERV filters. "acceptedAnswer": { This will be determined by both the frame size of the filter (usually close to the size of the return duct), and whether or not the filter has a pleated surface. That will result in more resistance to air passing through it. However, most HVAC systems built in the last 20 years should have no issue using a MERV 6 - MERV 13 rated air filter. It's quite interesting that the MERV rating itself is a metric used as a factor in the FPR rating. A filters pressure drop directly corresponds to a filters air flow rate. They used a 20 x 20 filter. Watch helpful videos from AFI. These values are shown to reflect the common vernacular used by many players in the filtration industry, Generally, the higher the MERV (M), you get better filter performance. 3.0-10.0 greater than or equal to 95%. In 2020, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommended switching from MERV 8 filters to MERV 13+ filters in order to help protect against the COVID-19 virus. These filters capture particles at 10.0 microns in size, including pollen, dust mites, and carpet fibers. The M in MERV rating stands for Minimum. As you can see, the HEPA filters surpass the most restrictive 0.3-1.0 micron particle size interval MERV rating is based upon. This chart shows their stated resistance to air flow in inches of water column (IWC/i.w.c.) ", MERV stands for Minimum Efficiency Reporting Value. Dust spot efficiency is a soiling index that It's a nationally controlled and governed rating system established by ASHRAE and is the most widely used ratings for most US-based filter brands. WHEN YOU NEED THEM. Manufacturers are in continual competition to try to provide the best of both worlds in this area. "@type": "Answer", Air Purifiers, Dehumidifiers and Treatment. "name": "Does the material affect the pressure drop of the filter? Commercial Buildings. Filters with higher MERVratings trap small particles more effectively than filters with lower MERVratings. "@type": "Question", However, if you are noticing that your air filter or smoke eater are not working as efficiently as it used to, or if you are constantly having to clean your air filters, it may be time to upgrade to a higher MERV rating. For facility managers this has provided a variety of challenges, including considerations around increased pressure drop in HVAC systems due to the more restrictive nature of filters with higher MERV ratings. Their cost is often moderate and are within many budgets. The manometer below shows my reading across one of the clean MERV-13 filters. Doing so could cause strain on your HVAC unit and could cause costly maintenance and repairs. "acceptedAnswer": { Filters rated MERV 7-12 are typically considered to be suitable for residential HVAC systems. They require special blowers to pull the air through them. All filters will increase in pressure drop in use. This value is used at the filters lowest efficiency. Fiberglass and washable filters are typically 1-4 MERV, and can filter out particles of 10 microns and larger. Because they go off the MERV chart, they are referred to as HEPA filters or high-efficiency filters. Average Particle Size Efficiency in Microns, 1.0-3.0 greater than or equal to 20% THE PRODUCTS YOU NEED, Additionally, some brands drop their MERV rating almost immediately upon first use (e.g., a so-called MERV-13 becomes a MERV-9 as its used it cant hold its efficiency). Save my name, email, and website in this browser for the next time I comment. February 2022. "acceptedAnswer": { MERV ratings are derived from the ASHRAE 52.2-2012 test which groups the particles sizes into three categories. You can check the whole EPAs list of air pollutants here. Pressure drop occurs, airflow is reduced and system . Includes a moisture resistant, high wet-strength beverage board frame. (std. ASHRAE no longer recognizes MERV 17-20 values. 3M Filtrete MERV 5 Review Conclusion. Weigh the test filter. ASHRAEdeveloped the MERV air filter efficiency rating system. Most current home HVAC units can accommodate a filter with a MERV 13 or lower. This rating system reports how well the filter captures and holds dust. When selecting the right filter for your application, higher is not always better. Airflow through the vents is lower: Is the new filter causing low airflow? There seems to be a lot of misunderstanding about the MERV rating of HVAC air filters and its effect on the pressure drop within the system. A MERV rating is a numerical rating system developed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) to rate the effectiveness of air filters. AFI Replacements (Air Bear, Honeywell, Trane), Poly Anti-Microbial Tackified 1 Inch Media 10oz, Poly Dry / Dry Tackified 2 Inch Media 15oz, Twist-Lock Cylindrical Cartridges for Pneuma Pulse, Flange-Top Cylindrical Cartridge for Farr Tenkay, Conical Cartridge for Donaldson GDX & GDS, Cylindrical Cartridge for Donaldson GDX & GDS, HEPA Crank-Lock Housing 2 Inch Pre-Filter, HEPA Crank-Lock Housing 4 Inch Pre-Filter, 2020 Air Filters, Inc. All rights reserved. "@type": "Answer", Tankless Water Heater Wire Size Calculator: What Gauge Wire (AWG)? MERV10, MERV 13, and MERV16) Pressure Drop Chart Static Pressures at variable CFM (in W.C.) Filter Number = 410 (MERV10), 413 (MERV 13), 416 (MERV16) CFM 400 = .03, .05, .07 CFM 800 = .07, .10, .13 1.0-3.0 greater than or equal to 95% MERV-15: Not a common filter efficiency, MERV-15 will sometimes be called a 95%+ filter as that was it's label under 52.1 This filter tends to get overlooked as it is between two very common high efficiency air filter values and although the static pressure is more comparable to 14 than 16, and the pricing is typically not too much more than 14, Do you know what could happen if you didnt get the right ones? Our filtration specialists can help you determine the right air filter strategy for your facility. 11 filters 11 merv 13 filters 13 merv 8 filters air air filter air filters air flow air purifier air purifiers air quality airborne airborne particles airflow allergens allergies allergy as dust as merv asthma bacteria best air by particle carbon carbon dust clean cleaner cleaning covid dust dust mites dust particles electrostatic filter filter's filtering filters filters air filtration furnace filter hepa hepa filters higher merv higher merv rating home home air homes household humidifier dust indoor air insecticide dust is merv large particles lead dust manufacturer manufacturers manufacturing merv merv filter merv rating merv ratings merv scale merv stands microparticle performance rating mold mold spores more particles my filter particle particle size particles performance rating pharmaceutical manufacturing purifier purifiers rating rating chart ratings refrigerating and air room sanding dust small particles smaller particles smoke technology these filters these particles this filter this rating to air tobacco smoke usa virus viruses water filters what does merv which merv which merv rating. For example, if bacteria ranges from 0.3 microns to 4 microns, the chart indicates a MERV 13 would be the minimum rating to select, and higher MERV-rated filters should be selected with the end users' level of comfort and "name": "What are the signs of unhealthy static pressure in an HVAC system? } Using an air filter with a MERV rating that is too high is as bad as using one that is too low. HEPA is a type of pleated mechanical air filter. air), Sensible Heat (BTU/hr) = 1.1 x CFM x t (std. We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites. Will it burn up your HVAC system? It is quite an important filter-specific factor. The scale rates how well a filter removes fine particulates from the incoming air. The vertical axis shows system static pressure drop by 0.1 inch w.c., and across the horizontal axis it shows system air flow in cubic feet per minute (CFPM). Well look at MERV 1-20 ratings in the MERV rating chart (youll find the chart further on). We cannot assume that the two AHUs operate at the same airflows, so the costs normalized for airflow are best used to make an estimate of annual energy savings by using 5-Star air filters. The Velocity (speed) of the air flow is tested at 1 of 7 different speeds. SEER = (1 EER100% + 42 EER75% + 45 EER50% + 12 EER25%)/100, Total Heat (BTU/hr.) They offer good airflow. Filters with higher MERV ratings are more restrictive because they are capable of filtering more particles than filters with lower MERV ratings. The MERV system rates air filters strictly on their ability to capture particles. LakeAir Commercial units have the ability to incorporate a MERV 14 High capacity media filter. As the MERV rating increases the media typically becomes loftier and thicker, to capture more air pollutants, with this you could see slightly more air restriction. "@type": "Answer", A MERV rating chart shows a numerical value. { This is how they get the name MERV (MINIMUM Efficiency Rating Value). 3. "text": "The pressure drop of a filter is a measure of its resistance to airflow through it. Grainger Editorial Staff. },{ The higher the number, the better the filter is at capturing larger particles between 0.3 and 10 microns (m). The higher the filtering efficiency rating (MERV rating), the higher the pressure drop. These ratings lie on a scale of 1 to 20. But lets start with what kind of particles are between 0.3 and 10 microns: Lets look at examples of two filters with 10 MERV and 14 MERV ratings. In case you havent heard of MERV before, it stands for Minimum Efficiency Reporting Value. The test is based on particle size. This multi-filter system extends the life of the more expensive final filters, leading to overall cost savings. High MERV ratings are recommended if you seek the removal of allergens from the air as the fibers they are comprised of are layered optimally to trap the smaller-size particles which are generally at fault for triggering symptoms in sensitive individuals. "acceptedAnswer": { For instance, the most common cause of pressure drop is a dirty filter and some low-quality MERV 13 filters will clog more frequently, leading to increased pressure drop which requires more frequent filter replacements. Install the test filter in the test duct and obtain clean air filter resistance or initial pressure drop. "@context": "https://schema.org", "@type": "Answer", ", Fedder can help you. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Copyright 2014-2023, PICKHVAC All Rights Reserved. Q&A Debunking Myths About MERV, Air Filtration . Building technology group ASHRAE has compiled recommendations for filtration, humidity set points, automation and more. Contaminant Size Intervals. This type of air filter can theoretically remove at least 99.97% of dust, pollen, mold, bacteria, and any airborne particles with a size of 0.3microns (m). Particles that are larger or smaller are trapped with even higher efficiency. These are the smallest particles that both FPR and MERV-rated air filters will be able to pick up. This could be because your system is moving too much or not enough air through its ductwork. The most prevalent MERV ratings are MERV 4, 6, 8, 10, 12, 14, and 16: A Higher MERV rating automatically means a better filter. Typical Applications. DC Wire Gauge Calculator: What Gauge Wire (12V, 24V, 48V)? The good news is that institutions and other commercial/industrial facilities can take steps to lower their operating costs by adjusting their air filter strategy, namely by using higher quality filters to save money in the long run. However, one study found that actual pressure drops in home. It assigns a single number to a filter in an effort to identify its minimum performance in removing particulate from an airstream. They also found that airflow in the high MERV filters decreased by 7% and 11% in the two HVAC systems compared to the low MERV filters. We are here to make sure you select the right solution for your needs. "@type": "Question", Rather, they use simplified words that everybody knows. Besides the basic need for good indoor air quality (IAQ), many extremely relevant reasons exist in 2020 to discuss air filters, according to Kathleen Owen, Fellow ASHRAE, member of the ASHRAE Epidemic Task Force, and Carolyn (Gemma) Kerr, Ph.D., Life Member ASHRAE. Which is not recommended, and could cause increased energy bills, and undue wear on your HVAC unit. MERV Rating:MERV is the Minimum Efficiency Reporting Value - The gist of MERV is a measurement of the smallest (minimum) particles a filter will effectively (efficiency) remove when tested - with test results that are verifiable and reportable (reporting value). You must have JavaScript enabled in your browser to utilize the functionality of this website. "text": "Filters use various types of medias depending on the application or what the environment requires. MERV Rating Chart Understanding MERV Ratings All filters have a MERV rating that falls between 1 and 16. JavaScript seems to be disabled in your browser. Before we look at the MERV rating chart (1-20 rating for 0.3 10 micron particles), lets answer this question: Do you know why HEPA filters are called HEPA? Conclusions Drawn from the MERV 13 Pressure Drop Chart $3,834 will be saved annually per AHU in reduced fan energy by using 5-Star air filters. Source: www.doityourself.com. Most manufacturers recommend ratings of 0.5 or lower for the IWC test. ", The "dirt" on the filters adds resistance. filtration helps provide healthier indoor air quality, Learn more about these recommendations here, recommendations for filtration, humidity set points, automation and more. A numerical chart with values from one through 20 from 1 to 20 measures how effectively the filter stops dust and other contaminants from merv merv rated merv rating merv ratings merv stands minimum efficiency reporting value microparticle performance rating mpr minimum efficiency reporting value mpr mpr ratings range from 1 20 rated rating ratings signify an air filter's effectiveness at reducing airborne particles and contaminants standard 52 5 minimum the minimum efficiency reporting value. A position paper published by ASHRAE looked at the claim that particle filtration has health benefits. PICKHVAC Terms of Use: Some of the products seen on our site are delivered through a relationship with outside suppliers like Networx.com, Google, and others. Products and solutions to help your business move forward. Your efficiency will drop measured by higher energy costs: Systems working too hard burn more fuel or use more electricity to get the job done. Frankly, that can happen with about any filter higher than a MERV 5 if it gets dirty and clogged. While it is true that the more resistance to the flow of air results in a greater drop in air pressure on the other side of the filter, it isnt always true that higher MERV means higher pressure drop. 1.0-3.0 greater than or equal to 80% A: Our current recommendation is to use a filter with a Minimum Efficiency Reporting Value (MERV) of 13, but a MERV 14 (or better) filter Is preferred. "@type": "Question", Browse a full list of industry terms to better choose your filters. While it is not important to fully understand the comparison chart, it is good to familiarize yourself with it. "@type": "Question", For example, a household pleated filter that uses synthetic media will have a lower pressure drop than a micro-fiberglass media that is used in critical environments such as a hospitals and datacenters. From ASHRAE Journal Newsletter, December 8, 2020 . This Standard is what led to the creation of the minimum efficiency reporting value, or MERV. "acceptedAnswer": { What are ionizers and other ozone generating air cleaners? This has resulted in confusion and apprehension on the part of the homeowner who wants to provide good quality indoor air, but not at the expense of that expensive HVAC system. ; This scale addresses particles that scope in size from 0.3 to 10 micrometers. A MERV Rating indicates a score from 1 to 16 for residential air filters sold in the United States and 17 to 20 for commercial air filters. Also, just because a filter fits with a system, that doesn't mean it's the best filter for the system. Upgrade your filter to a MERV 13 rated air filter to protect your home or business from the spread of viruses and illnesses. This level of filtration does fall into the MERV system but they are shown here to add continuity to the overall filter picture. },{ Do a quick search online using MERV in your question and youll see statements such as, Higher MERV means higher pressure drop. OR Higher MERV filters can destroy your HVAC system. These statements are presented as set-in-stone, hard facts that are not to be refuted. Many pleated HVAC air filters can still have a high MERV rating, while not drastically restricting air flow. OurHEPA filtersystems are our best media air filters they remove 99.97% of all impurities. The chart below shows a detailed description for each merv rating 1 through 16. This depends on a variety of factors, including the type of air filters you have, the size of your home, the number of people in your household, the presence of pets, and your own personal preferences. This one of the main reasons why it is so important to check, change, and clean your air filter every month to help ensure your air filters pressure drop does not get too high and cause strain on your air conditioner/handler. However, if you are trying to filter out COVID-19 virus, they call for a MERV 13 or as high as your system can accommodate. These filters remove at least 99.97% of dust particle and are capable of removing viruses and radioactive material. This allows greater airflow without having to increase the size of the actual filter. He holds an HVAC associate degree from Lone Star College and EPA & R-410A Certifications. Industrial Filtration Process: Why Its Important and Its Uses, How Often to Change a MERV 13 Filter: Everything You Need to Know, MERV 13 vs HEPA Filter (What Are The Differences? "name": "Do higher MERV rated filters restrict air flow? Filters use various types of medias depending on the application or what the environment requires. To get the right HVAC product and suitable MERV-rated air filter, you should know the area you want to use. },{ A filter's MERVnumber indicates how it's rated to remove these particles. Thats why air filter producers dont usually specify the MERV rating. The test results are then used to give a filter its MERV rating. The dirty MERV-8 filters had lower pressure drops than the clean MERV-13s. The Minimum Efficiency Reporting Value (MERV) rating indicates the effectiveness of an air filter (from 1 to 20) at trapping particles suspended in air. It ensures reliable and consistent testing of air filter performance. MERV stands for Minimum Efficiency Reporting Value. The lower air pressure will then cause wasted energy because the HVAC system will need to spend more time and power to heat or cool the building to the desired temperature. As a result, we cannot show you the price in catalog or the product page. They are not Minimum efficient. },{ "@type": "Question", While it is true that the more the air filter traps the more effective it is at capturing more particles; it will eventually become too loaded, at which point, the airflow could be zero and extremely restrictive. The 3M Filtrete MERV 5 review concluded that this furnace filter is a good choice for any household as long as there are no allergy issues, pets such as dogs and cats, smokers in the house. Thats the size interval that includes most air pollutants smoke, dust, cooking oil smell, mold spores, and bacteria, to name just a few. "@type": "FAQPage", If the light is significantly blocked, install a new filter. In January 2009 ASHRAE stopped recognizing MERV 17 -20 values. The MERV rating is determined by the size of the particles that the air filter can remove, with the smallest particles being the most efficient at removing. A flat design with a MERV 13 would be too restrictive. You can see from the MERV scale above that MERV 10 filter will filter out 85% of 3.0-10.0 m particles. Use this rating system compare filters made by different manufacturers. The pressure drop across the MERV-13 filter was 0.0274 inch of water column. The most prevalent MERV ratings are MERV 4, 6, 8, 10, 12, 14, and 16: MERV Rating In Air Purifier Specification Sheets (Or Lack There Of) A Higher MERV rating automatically means a better filter. As an Amazon Associate we earn from qualifying purchases. This system is designed by the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE). MERV values range from 1 (minimal filtering) to 20 (maximum filtering). When a particle is in the 0.3 to 1 micron in size it is considered microparticle. How to Tell if I Should Change Furnace Filter. At LakeAir, we recommendMERV 10 filtersas our good air filter. What MERV filter is recommended for preventing the transmission of airborne illnesses such as COVID-19? They specify a minimum MERV of a filter to use, but not the IR. Similarly, the medium MERV filters also showed a decrease in airflow . In other words: HEPA filters are better than anything MERV rating can measure. This results in lower air pressure on the side of the filter from which the air exits. They remove the bulk of dust we see in homes and offices. The FPR system goes a step further and also rates filters based on the amount of pressure drop they introduce and their dust holding capacity. the expression of the Minimum Efficiency Reporting Value (MERV). You can see from the MERV scale above that MERV 10 filter will filter out 85% of 3.0-10.0 m particles. Extended Surface Pleated Filters Standard and high capacity MERV 8, MERV-A 8-A Low Initial Resistance for energy savings . What is a MERV rating? MERV 13 Pressure Drop Chart (Click to Zoom). However, an important factor is that MERV ratings are not standard and the quality of a filter will vary from one brand to the next, meaning that pressure drop will vary between different filters that are rated the same. It should be noted that pressure drop through a high-MERV filter varies depending on the velocity of the air flow. The rating system is called ASHRAE Standard 52.2-2007. Weve identified that there is an increase in pressure drop and energy costs when switching to MERV 13 or higher filters. Need more details? The higher the filtering efficiency rating (MERV rating), the higher the pressure drop. "@type": "Answer", } Electrostatic air filtration is not easily compared to media filters. The range is from 1 (lowest efficiency) to 20 (highest efficiency). "name": "How does filter pressure drop affect flow rate? Minimum Efficiency Reporting Values, or MERVs, report a filter's ability to capture larger particles between 0.3 and 10 microns (m). Final filters may be used alone in a single-filter system, or they may be used in combination with one or more pre-filters. air). A filters pressure drop changes throughout its use. If U are going to use pleated filters U need a deep pleated filter to provide a lot more area; which would require new Return Air filter racks . Its and apples and oranges kind of thing. Likewise, the mid-MERV filters also showed decreased air flow relative to the low-MERV filters, this time 3% and 8% lower in the two systems. You will find exactly the same MERV rating chart there in a bit more technically language. Has the lowest pressure drop of any fine fiber 4 deep mini-pleated filter. An air filter's minimum efficiency reporting value (MERV) rating measures how effectively the filter stops dust and other contaminants from passing through the filter and into the air stream. As the MERV rating increases the finer the filtration becomes. ", "acceptedAnswer": { Each air filter has its own unique pressure drop. The test duct fans can operate up to a speed of 750 fpm. The lower the pressure drop the easier it is for air to flow through the filter. Readers with specific questions should refer to the applicable standards or consult with an attorney. Brown and Christopher L. Cox, eds. Heres one example: We compared three filters of a popular brand and the same size (20x25x1) with MERV 5, MERV 11 and MERV 13 ratings. The wasted energy (and associated energy bill costs) required to push air through a higher MERV-rated filter to overcome the increased pressure drop shocks some owners. Pros of a MERV 12 Air Filter The accepted pressure drop is different for each air conditioning or air handling system, and you should always refer to your manufacturers guide prior to inserting replacing your air filter to ensure you are using the appropriate filter. As an air filter manufacturer, we are uniquely positioned to custom make any and all types of air filters. Since filters with a higher MERV can trap smaller particles, it is often assumed that they will automatically have a greater resistance to air flow. As dirt and debris gets trapped by the filter, there is less space for air to pass through, causing the pressure drop to rise throughout the filters life. This MERV rating chart has the MERV ratings, 1-16 on the left hand column and then there are five other columns showing the average efficiency in microns, average arrestance and the final resistance as measured in inches of water.