Choosing the Most Efficient Air Cleaner for Your Home
By Mike Gunion and Joe Castner
Choose the Most Efficient Air Cleaner for Your Home
You can get a whole home air cleaner if you have a forced air system, meaning you have a furnace or furnace and air conditioner. Then you already have a basic mechanical filter. That’s your first, crude level of defense against air pollution. These mechanical filters are typically made of a coarsely woven metal. They can only remove large particles of dirt and hair. Even that capacity is greatly reduced when the filters are not replaced regularly. Worse yet, these mechanical filters can’t capture the tiny RSPs. If you do not have a forced-air system or want to consider a portable, room-only device, here’s the basics you need to know.
Get a Portable Room-only Device or a Whole Home System?
The next step is to choose between a portable room-only cleaner and a whole home cleaner. Unfortunately, some don’t have that choice. You can’t get a whole home system if you do not have a forced-air home furnace or air conditioning system.
In considering portable devices you have two kinds: ones with mechanical filters or ionizers.
Mechanical Filter-Based Portable Air Devices
The best kind meet the HEPA (high efficiency particulate air filters) standard. That means they can capture 99.97 percent of the airborne particles 0.3 microns and larger that pass through the filter. These include tobacco smoke, household dust and pollen. Mechanical filters draw air through a flat, pleated or high efficiency particulate air (HEPA) surface to trap particles. That design means HEPA filters can be efficient in the beginning yet tend to clog easily. Clogging reduces airflow and thus their ability, over time, to remove pollutants. Filters must be changed with some frequency to maintain HEPA-level efficiency. Not all if us remain that diligent, even if we intend to be. “Gary McEldowney, the marketing director for AllergyBuyersClub.com, said the cost of a purifier could range from $150 to $700, depending on size and features. Replacement HEPA filters cost $40 to $150.” Other models are much more expensive.
Another obvious disadvantage is that a single room cleaner can’t keep the rest of the air in your home clean. It can’t even maintain the high HEPA standard in the room in which it is used, unless it runs continuously and the door and windows to the room are kept closed – an unlikely possibility. This room-only approach is akin putting a bandaid on a wound. Portable Room Ionizers Ionizers emit a small charge to the air stream that cause particles to adhere to the filter or other surfaces by a magnetic-like attraction. But this is not efficient as particles can become re-suspended. Worse yet, ionizing emits ozone, a lung irritant that is also linked to other health problems. It can have damaging health effects, especially for those with asthma and other lung diseases, children and the elderly.
According to Consumer Reports and the EPA, “While some indoor air pollutant concentrations decline in the presence of ozone, other pollutants increase. In fact, upon reaction with ozone, some previously undetected, toxic chemicals emerge in indoor air, including formaldehyde and other aldehydes.” See the EPA’s "Ozone Generators Sold as Air Cleaners." To add insult to injury, the units make a zapping and other noise as they emit ozone. Also it requires time-consuming cleaning and frequent filter changes to maintain even a lower level of performance.
- http://www.healthgoods.com/education/healthy_home_information/Indoor_Air_Quality/iaq_particles.htm
- http://www.allergyclean.com/article-formaldehyde.htm
- http://www.housekeepingchannel.com/a_337-Consumer_Reports_Testing_of_Sharper_Image_Ionic_Breeze_Professional_with_OzoneGuard_Now_Available_Online
As you can see, your best option, if you cannot get a whole home system is to get a portable device with a mechanical, HEPA-grade filter. If your home has a forced-air system so you can get a whole home system, you’ll now see your options. The good news is that there are clear choices. You do not have to spend a lot of time nor money to get healthy air throughout your home.
How to Choose the Most Efficient Whole Home Air Cleaner
Whole home air cleaners can be placed in the ductwork of forced-air systems heating or air-conditioning (also known as in-duct air cleaners). “If you are using forced air for, the best way to clean the air in your house is to add a filtration module to your system,” said Alex Wilson, president of BuildingGreen in Brattleboro, Vermont.
Now, however, you don’t have to mess with the ducts. Instead one kind of high-efficiency air cleaner can be retrofitted, that is bolted right onto your existing unit. Here are the kinds of whole home air cleaners from which you can choose: Electrostatic Precipitators (ESPS) All electrostatic precipitators use electricity to charge particles passing through them and then attract them electrically (make them “stick”) to either plates or a filter.
As you compare systems consider these five key factors:
- Performance over time: Efficiency goes down over time in some systems.
- Maintenance: It is key to continuously high performance. Some systems are considerably more complex, messy and time-consuming - as are some filters. Even a diligent person can get tired of the upkeep and avoid doing it. Some systems require more frequent filter changes than others.
- Ease and cost of installation.
- Sound: Some systems create noise while others are quiet.
- Ozone: The pollutant in smog, ozone can cause lung damage and other health problems. It also creates noise as it arcs, sparks and pops.
They are described below according to increasing levels of air cleaning performance, maintenance needs and convenience.
Electrostatic Filters
This is the least expensive kind of filtering system, removing 90% of particles that are 0.3 microns or less. It requires frequent filter changes and, more importantly, performance goes down over time. One example is the Filtrete. Electrostatic units filter the air using static electricity. They have a static charge on the filter to allow airborne particles to "stick" to the filter, just like static-charged clothing sticks together. The drawbacks to these units are that they capture fewer RSP’s and the filter needs to be replaced frequently.
Conventional Electronic Air Cleaners
EACs charge particles and cause them to stick to plates inside the unit or to a filter. In this way they trap and filter up to 98% of pollutants from the air passing through your heating and cooling system. This kind of air cleaner can capture microscopic impurities like dust, smoke and smog particles in addition to larger particles like mold spores and cat dander. Collected pollutants are removed by cleaning the plates in the sink or dishwasher. Some EAC’s use grounded filters instead of plates but these require expensive replacements (Aprilaire) or messy cleanup (Trane). http://ecotips.sustainablelawrence.org/2008/07/breath-of-fresh-air.html
Hybrid Electronic Air Cleaner
AspenAir Inside is a hybrid. It eliminates the need for wires (or pins) and plates. Instead it uses a non-metallic material to conduct the electricity and charge the RSP’s. Thus you can avoid the messy and time-consuming cleaning that comes with metal-based technology. Then, it uses an inexpensive but highly-efficient, loosely woven filter to capture the particles. This loose weave allows the unit to operate with low static pressure. It is quick and easy to replace every six months or a year. Thus, you can get continuous high performance without the downsides (higher maintenance, costlier installation, etc.) of conventional EACs.
Act Now. Winter is coming. You’ll be spending more time inside. Find a competent local contractor to install your AspenAirInside. Email or call us if you would like a referral to one. Also call if you would like to know more or have questions, plus see topics covered on our site and blog. We look forward to serving you in making your home healthier.
Put AspenAir Inside Your HomeRemove from your home air 99% of the harmful Respirable Suspended Particles (RSP) that can lead to asthma, allergies and other respiratory and heart conditions, using Aspen Air Inside. It removes up to 20 times the particle matter of conventional systems, making your indoor air better than fresh air.
Only AspenAir Inside Can Provide All These Benefits
- Continuously safe indoor air without purchasing a new HVAC system
- Quick, simpler, non-intrusive and less expensive installation.
- Much less maintenance. (No wires to scrape, plates to clean, or surfaces to vacuum)
- Visible diagnostic system to see your system is working
- Fewer filter changes (1-2 a year, taking ten minutes or less)
- No harmful ozone emitted.
- Quiet (no zapping caused by ozone).
- Less energy to operate
Installation is Easier and Less IntrusiveUnlike other kinds of electrostatic precipitator retrofits that must be installed in the duct of forced air furnaces, AspenAir Inside can be bolted right onto any heating or cooling system. Your contractor can place it in the return air grille in 40 minutes or less. That is simpler, faster and eliminates the danger of damaging walls or other parts of the HVAC system. Further, because it is easier to access, it makes maintenance much easier.
Maintenance is Simpler and Less-Time Consuming. Other whole home systems’ maintenance is more complicated, time-consuming and prone to mistakes, some emit the harmful ozone that also causes noisy arcing and sparking, and require more maintenance including more frequent filter changes.
AspenAir Inside. Better Than Fresh Air.
Comments
| kare Anderson
February 23, 2009 |
Many health-minded homeowners also want green features such as ways to save energy (and money) |
| Heating Repair in Phoenix, AZ
December 07, 2009 |
Thanks for this entry. I have been searching for the perfect air cleaner or purifier. I have a demanding household – I have two kids below 4 years old, a dog (and getting rid of it is not an option), and a husband who smokes. I need to keep the air inside the house clean so as not to endanger my family’s health and not expose them to bacteria in the air. |
