They usually have the lowest MERV of all filters as well. Thats the size interval that includes most air pollutants smoke, dust, cooking oil smell, mold spores, and bacteria, to name just a few. The amount of the HVACs air flow slowed by the filter is equivalent to the filters pressure drop. As an Amazon Associate we earn from qualifying purchases. "text": "When you air filter is installed, it is a barrier between your HVAC and your ducts/vents. Grainger Editorial Staff. The material used to make the filter. These air filters are great for people with pets. build your custom filter now, Send us a message below or call us at 1.800.667.8563. Using an air filter with a MERVrating higher than what your furnace or air conditioner manufacturer recommends can actually impair its performance. Airflow through the vents is lower: Is the new filter causing low airflow? What Are All Those Gadgets On A Multitool? "text": "A filters pressure drop directly corresponds to a filters air flow rate. ; This scale addresses particles that scope in size from 0.3 to 10 micrometers. "@type": "Question", A filters pressure drop changes throughout its use. The more tightly woven or thick a filters media is, the more particles and contaminates the filter can trap. Contaminant Size Intervals. "acceptedAnswer": { These air filters are used to protect people or products from airborne contaminants. But before you update the filter, make sure it's specific. Two 14X14 filter grilles are way too small. At LakeAir, we recommendMERV 10 filtersas our good air filter. The scale rates how well a filter removes fine particulates from the incoming air. The higher the MERV of a filter, the smaller and the more particles it will remove from the air that passes through it. "@type": "Answer", It is measured in Pascals in the SI system." This website uses cookies. These include mold, smoke and pollen. ", The blowers in HVAC units rely on a good air supply to keep them cool. During each cycle a predetermined amount of dust particles is released into the airstream. What are the benefits of a higher MERV rating? Many pleated HVAC air filters can still have a high MERV rating, while not drastically restricting air flow. Pressure drop directly corresponds to a filters air flow rate. was at various amounts of airflow in cubic feet per minute (CFM). The final pressure drop/final resistance is measured when the filter has reached its total dust holding capacity and is ready to be replaced. The speed at which the test was done is noted in the test results. These are the smallest particles that both FPR and MERV-rated air filters will be able to pick up. MERV Rating Chart Understanding MERV Ratings All filters have a MERV rating that falls between 1 and 16. We recommendMERV 11 filtersas our better air filter. Upgrade your filter to a MERV 13 rated air filter to protect your home or business from the spread of viruses and illnesses. air), Latent Heat (BTU/hr) = 0.69 x CFM x gr. This level of filtration does fall into the MERV system but they are shown here to add continuity to the overall filter picture. It shows particle size ranges. ASHRAEdeveloped the MERV air filter efficiency rating system. Frequent filter changeouts will help minimize risks from pressure drop. In the most basic sense, the MERV rating gives us an idea of how well filters (air purifiers, furnaces) can filter out 0.3 to 10 micron (10-6m) particles. The MERV rating is a measure of the ability of an air filter to remove particles from the air. Also, just because a filter fits with a system, that doesn't mean it's the best filter for the system. "mainEntity": [{ 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). },{ They begin at MERV 1 and go as high as MERV 20, with filters rated MERV 16 through 20 being mainly used in hospitals, research laboratories, computer labs, etc. They are not Minimum efficient. Can I purchase a 2x14x20 air filter with rating of 20, or 30 if possible, online? According to theAmerican Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE),this filtration helps provide healthier indoor air quality. The mid-MERV is twice as much and the high-MERV is three times as much. Rather, they use simplified words that everybody knows. Your HVAC equipment will give off a few clues that the filter is too restrictive and creating unacceptable pressure drop. A filters pressure drop directly corresponds to a filters air flow rate. ", How do I know if I need a higher MERV rating? 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. This helps improve indoor air quality and prevents the build up of contaminants in equipment and damaging it. 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. },{ Efficiency is measured by the percentage of particles captured. 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. It is quite an important filter-specific factor. 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. ", } 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 . If you dont have, or cant find, the owners manual for your HVAC system, here are the recommendations of three agencies. "@type": "Question", The higher the MERV rating the better the filter is at trapping specific types of particles. Fedder can help you. Well look at MERV 1-20 ratings in the MERV rating chart (youll find the chart further on). These dust particles fall into three size groups. They remove the bulk of dust we see in homes and offices. 14 Culprits To Check For Now, MMBTU To MMSCFD Calculator For Natural Gas + Chart, 8 Best Infrared Heaters For Indoors, Patios, Garages (With ECO Thermostats), AGM Battery Voltage Charts: 12V, 24V Deep Cycle Battery Voltage, Lead-Acid Battery Voltage Chart For 6V, 12V, 24V, 48V Batteries, Natural Gas MMSCFD To MMBTU/Day Calculator + Chart, Smoke, dust, oil smell, bacteria, sneeze droplets, Car emissions, bigger dust particles (lead), Legionella, Hair spray, mold spored, mite debris, fabric protector, cat, and dog dander, Pollen, sanding dust, cockroach debris, textile fibers, 85% for 3.0-10.0 m particles, or greater, 90% for 3.0-10.0 m particles, or greater. I know that filter may look pretty dirty, but the light . A filters pressure drop is measured twice, once when the filter is brand new and again when the filter has been in service and is loaded with trapped air pollutants. In fact, they are high-efficiency filters. The amount of E1, E2 and E3 dust particles that are captured and missed is calculated. When a filter is in use, it traps and gathers particles, the more particles that are trapped the harder it is for air to pass through; when this occurs the filters pressure drop rises. 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. 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. 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). Even filters sharing the same MERV rating may have differing pressure drops. What is a MERV rating? Minimum Efficiency Reporting Values, or MERVs, report a filter's ability to capture larger particles between 0.3 and 10 microns (m). 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. Using the MERV rating chart to understand the filters and their applications. The majority of residential HVAC systems use a 1" thick filter, but filters are available at 2", 4" and 5" thick. MERV stands for Minimum Efficiency Reporting Value. Since it collects more particles, its likely to get dirty more quickly than some other filters. Their average efficiency from 3 to 10 micron is less than 20. These filters are used primarily to protect equipment. What is interesting is that youll rarely see MERV rating in an air purifier specification sheet. 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. }] Filters with higher MERV ratings trap small particles more effectively than filters with lower MERV ratings. },{ 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. ", "@type": "Answer", Improved indoor air quality by capturing more particles, a higher MERV rating results in cleaner air being circulated throughout the home or office. Close pleats in 5" depth minimize pressure drop and extend filter life example: Source: www.merv8.com Pressure drop occurs, airflow is reduced and system . Typically, the higher the MERV rating, the higher the pressure drop and the more restrictive the air flow is. Other materials used for filters have different MERV and air flow (IR) properties. Ultimately a dirty filter will have the same impact on an HVAC system as using a filter with a MERV level that is too high for the equipment. It should be noted that pressure drop through a high-MERV filter varies depending on the velocity of the air flow. The chart also provides instructions on how to determine electric fan energy consumed by AHUs in your own facility. "text": "The pressure drop of a filter is a measure of its resistance to airflow through it. Particle filtration can be "modestly effective" against allergy and asthma symptoms. WHEN YOU NEED THEM. Average 1-6 Person Home kWh Usage, Gas Vs Electric Water Heater Monthly Cost Comparison (State-By-State), Water Heating Costs For 1,2,3,4,5,6 Family Homes (State-By-State Analysis), Electric Water Heating Cost, kWh Usage Per Month (State-By-State RECS Analysis), What Is W2 Wire On Thermostat? DC Wire Gauge Calculator: What Gauge Wire (12V, 24V, 48V)? "text": "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. The MERV system rates air filters strictly on their ability to capture particles. It also shows air filter efficiency levels. "@type": "FAQPage", They used a 20 x 20 filter. Building technology group ASHRAE has compiled recommendations for filtration, humidity set points, automation and more. Available in a variety of sizes for virtually any application. There is a relationship between filter efficiency and pressure drop and resistance. To build some good comparative data we tested 20 different air filters of various types, thicknesses and efficiencies. Calculator + Chart (Natural Gas), Average Gas Bill For 1-Bedroom Apartment: State-By-State Cost Analysis, Average Electricity Bill For 4 Person Household (Survey Analysis), How Many kWh Per Day Is Normal? commentary on the MERV scale when it first came to light in 1987: (MERV rating) represents a quantum leap in the precision and accuracy of air purifiers. Commercial Buildings. ($0.05 $0.22/h), How Much Does 1000 Watts Cost Per Hour? Browse a full list of industry terms to better choose your filters. 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." Tankless Water Heater Wire Size Calculator: What Gauge Wire (AWG)? 0.3-1.0 m MERV and Pressure Drop What Makes the Difference? I know you're dying of the suspense now, so here are all the measurements. "name": "Do higher MERV rated filters restrict air flow? 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. As you can see above, research shows that in general, HVAC systems with high MERV* filters have a higher pressure drop across the entire filter. SEER = (1 EER100% + 42 EER75% + 45 EER50% + 12 EER25%)/100, Total Heat (BTU/hr.) What are they and why they matter? ", How efficient the filter is against all three size ranges is compared against a MERV chart and the final MERV value is the highest value where the filter meets all three requirements of MERV. You can see from the MERV scale above that MERV 10 filter will filter out 85% of 3.0-10.0 m particles. When a filter is in use, it traps and gathers particles, the more particles that are trapped the harder it is for air to pass through; when this occurs the filters pressure drop rises. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommends a minimum MERV of 6 as their general rule for home HVAC systems. There are many benefits to having a higher MERV rating, including: If you have a high MERV rating, you should change your filter every 3 months. 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. 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. Take it out and run the system for a couple minutes. 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. The MEGApleat M9 filter is the longest-lasting and strongest MERV 9 pleated filter on the market. 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. You can help minimize the risk of HVAC equipment issues or damage from pressure drop, by regularly changing your air filter. While these numbers are fairly close, at least in this example the filter with a MERV of 11, which is more than twice the MERV 5, had a lower resistance to air flow. The performance is based on particles that are 0.3-10 micron in diameter. Below is a chart comparing the pressure drop of standard 20X24X1 MERV8, 11, and 13 at 1000 CFM. They never need to be replaced. 1994-2021, W.W. Grainger, Inc. All Rights Reserved. The Air Conditioning Contractors of America assumes that the pressure drop across a . This allows greater airflow without having to increase the size of the actual filter. The "dirt" on the filters adds resistance. Additional annual savings of $2,413 are realized via lower change out costs, reduced solid waste, reduced CO2 emissions AND lower purchase price. A MERV rating chart shows a numerical value. Note that when the MERV 13 is added, it is more restrictive than either. In addition, poorly designed and installed duct systems already have external static pressures that are too high. A 1 MERV 13 pleated filter has a pressure drop of around 0.27, and a 1 MERV 8 has a pressure drop of around 0.14. A filters material type and efficiency rating affect the pressure drop and resistance to air flow. 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. Not as taxing on your HVAC system. Increased efficiency of the HVAC system a higher MERV rating means that the filter is able to capture more particles, which leads to a more efficient HVAC system. MERV, which is an acronym for Minimum Efficiency Reporting Value, is a rating system that was developed by ASHRAE (the American Society of Heating, Refrigerating and Air-Conditioning Engineers). The chart below shows a detailed description for each merv rating 1 through 16. 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. Rene has worked 10 years in the HVAC field and now is the Senior Comfort Specialist for PICKHVAC. This part is common to the three previous studies. Firing Ranges. } Thick and high-MERV filters can cause a significant drop in pressure inside your HVAC system from before to after the filter. Includes a moisture resistant, high wet-strength beverage board frame. "name": "What is the relationship between filter pressure drop and air flow rate? air). And MERV-13* is practically where you want to be. Other Signs your MERV is Too High / Your Filter Too Restrictive, Can I Temporarily Run My Furnace Without a Filter, Relationship Between Pressure Drop and MERV Rating, Do Not Use High MERV (12+) Filter for HVAC. Again, it has a pleated design. 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. MERV rating. MERV stands for Minimum Efficiency Reporting Value. Riga-Flo A: Although ASHRAE does not recommend a specific MERV filter rating for preventing COVID-19 transmission, the organization suggests that upgrading systems in non-healthcare facilities to MERV-13 or the highest achievable level can be a worthwhile step in emergency response plans. Cookies Policy. We will help you understand your best air filtration options. The resulting rating is theen given to each filter. 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? While its helpful to know something about the relationship between MERV and pressure drop, it isnt generally something that you should lose any sleep over. THE PRODUCTS YOU NEED, Diagonal support members on both sides ensuring filter pack rigidity. An air filters pressure drop is the measurement of resistance to air that passes through the filter. Low initial resistance and high dust holding capacity requires less energy consumption, resulting in lower operating costs and energy savings. The filters initial pressure drop (initial resistance) will vary by the filter type, MERV rating, and size. We offer a variety of high quality Camfil-brand filters that can help you meet the latest filtration recommendations while keeping energy costs as low as possible. Resistance is measured in inches water gauge (w.g.) Products and solutions to help your business move forward. 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. They generally allow enough air to flow through a furnace filter to allow the blower to stay cool. It is a rating system incorporated into the test specification of ASHRAE 52.2. 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. ASHRAE no longer recognizes MERV 17-20 values. Spun fiberglass almost always has a lower IR than other materials. Pressure drop directly corresponds to a filters air flow rate." The filter has a Galvanized steel frame, the filter dimensions are 20 x 19.75 x 3.75. Because the pleated design creates more surface area, which is a less restrictive design. We may or may not be compensated for purchased you make as a result of our recommendation. Standard 52.2 establishes a testing protocol. The test duct fans can operate up to a speed of 750 fpm. } achieves MERV 8 rating before and after a conditioning step Independently tested and verified for quality control Support GridExtremely low pressure drop and high dust holding capacity Construction: