This question is most often asked by homeowners who don’t have central air conditioning systems. An example would be something like this. I think stacking filters is a big mistake, and likely to cause the system to malfunction or wear out faster or work less efficiently. Finding your air return ducts can be a bit like a scavenger hunt. Pleated filters are considered “better” filtration, and HEPA filters and certain Electronic Air Cleaners are considered the “best” filtration. For you experts out there, is this an acceptable practice? Although the two sides of an air filter might look the same, they are not. Thick filters, due to their increased surface area, also have other benefits like: Higher dust-holding ability (meaning it can catch a lot without blocking airflow) Longer life (most pleated 4-in and 5-in-deep media filters will If I hold the shaft still, the coils are acting as a transformer into ... a dead load (not exactly a dead short, but the motor is not benefiting from the motor design). Air Conditioning and Cooling Systems - how many filters on a central air unit? Its a small house, but there are so many walls and three bedrooms. I'll look into those filters! What are you doing for heat? The more particulates that are trapped, the fewer get stuck to the interior of your vent work, and the better the airflow becomes. Air filters are a central, but often under-appreciated part of a central HVAC system. Thanks Ryan Hughes! The bottom of the line permanent filters are roughly replacements for your cheap filter, they filter out birds and small children. First and foremost, your air becomes cleaner, which can help improve the longevity of your HVAC system. Just a reminder, a lot of your cars have cabin air filters too. Therefore, your home may have air filters located at the air handler AND in the returns. Radiant floor heating - want warm floors, cool room. Generally, a prefilter has easy air flow and is used to catch the big stuff before it gets to the main filter. Pleated air filters remove around 35 to 40% of the air pollutants at home. Bottom Line: Putting two filters will not make it last longer but may make you have to replace it earlier, assuming it doesn't already reduce air flow too much with just the filters. The bottom of the line filters won't meet your needs, since you're using a cheap filter to keep big stuff out of a pleated filter. The squirrel cage blower is designed to move a column of air, "restriction and if taken out of the unit and set in the open, then it would overload the motor. Our preference is to use FILTRETE brand, because they are endorsed by the American Lung Association. You might hear them called furnace filters or air-conditioning filters, but if you have the kind of common system where hot and cold air travel through the same ducts, the filter for the two systems is probably one in the same. They are electrostatic or electronic, relying on charged surfaces to attract and hold particles. lowering/raising the ambient temperature. Causes for Central Air Conditioner Freezing Up . Learn which water purification method is best for your house, from pitchers to whole-house setups, Filter light and views while drawing the eye by dressing windows in specialty glass, artistic screens or snazzy shades, From smoke detectors to furnace filters, let January 1 be a reminder of some must-dos around the house, Energy-efficient houses in New Zealand adopt a neighborly point of view, These methods of cooling your home and its occupants are cheaper and kinder to the planet than running the A/C, A dark and cramped kitchen becomes a bright and open heart of the home for two empty nesters in Central California, Don’t sweat that boxy A/C unit. Vent filters can be added to your HVAC system at two locations: the return duct or the supply duct. mini split for ac with rooom-to-room fans instead of central ac. Black dust in your air filter could be caused a number of things, such as: 1. Check your thermostat settings. That would require a minimum filter size 20 x 30. They are more effective than other mechanical air filters because they contain more fiber per square inch as compared to disposable fiberglass filters. Ducted HVAC vs. radiators and ductless/ mini duct A/C and heating units in each room? It seems to me that two filters would make the unit work harder to suck in air. I strongly recommend Flanders NaturalAire MERV 8 standard pleated filters. The arrow should point towards the blower, and point away from the return air duct. Placing more and more and more back pressure on a motor absolutely draws more current, as noted in the previous post, heat is generated! http://hvacrfundamentals.blogspot.com/2009/08/understanding-centrifugal-fan-motor.html, https://yorkcentraltechtalk.wordpress.com/2012/09/11/what-is-an-ecm-motor/, https://yorkcentraltechtalk.wordpress.com/2012/07/20/air-flow-effects-on-air-conditioning-revisited/. Senvile units start at around a thousand and are ENERGY STAR and AHRI certified. Black Soot. Also most blowers run the risk of overheating if CFM is reduced too much. Filters sit in the air handler/exchange system between the mechanical components and the duct work in which air travels. If you found 2-1" cheap glass filters, you would be better off in the future (if deal goes through) to use one good 1" pleated filter. People often forget that air is matter & it has volume. Remember, this is the air … You mention that we need to move the air intake to another room. So it is backwards from what most people think. Multi stage filtering is not a bad idea, and is done in many environments (especially commercially) for the same reason you asked, bringing only the pre-filtered air with whatever remains to the more expensive staged filter. (Not sure how we could make that look good aesthetically speaking.) My thoughts on the OP question,try it, but it might be useful to pay for a duct cleaning. MERV ratings go right up to 15+, not seen on residential systems though as these are enhanced HEPA, that won't work on standard blower systems. If the fan blades are moving less air, they can actually spin easier because there is less air to sling. Where would you put a second intake? For any other kind of system, look for the air filter behind the return air grill on the wall, ceiling or utility closet door. It seems you have a better understanding of the theory and not the practical applications and you have failed to understand the simple thermodynamics of a central air system. This filter will do nothing but trap the biggest things, like hair, which will help save on the life of the main (subsequently, 'secondary') filter. Type 2 - Pleated Air Filters. I would strongly recommend against using two filters at once, especially if it is just by reason of convenience. Restricting the airflow reduces the load on the motor until a point of diminishing returns at which the motor is at the rated speed and moving the optimum amount of air. Putting in two filters might temporarily address the 2nd factor but it will have a negative impact on CFM and may, in fact, require that you replace the filters more often. I would ask the owners about that, just to be sure. 3. They require professional installation because the air handler generally needs duct modification to accommodate it (they're 6 to 7" wide and don't fit a standard filter compartment). You do trade the convenience of simple replacement for the need to wash them regularly, typically on the order of every month to every few months. One filter is PLENTY. I replaced two trane 20 year old system s with dual speed trane 18 seer. 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