A purifier that's too small may struggle to adequately clean the air in larger spaces, while one that's too powerful for a small room could be unnecessarily loud and consume more energy than needed. Let's not forget, different types of rooms have different air purification needs depending on what happens in them.
The higher the CADR, the larger the area the air cleaner can serve. It is important to select a room air cleaner specific for your room size. A general rule to consider is the “2/3 rule” – find an air cleaner with a CADR that is at least 2/3 the square footage of the space.
Buying an air purifier that is too big for your room is an unnecessary waste of money and energy. Doing some simple math can help you find just the right size unit for your room.
Interestingly, it's more beneficial to have multiple small air purifiers distributed throughout each room rather than relying on a single large one to purify the entire house. Air purifiers typically don't have the capacity to effectively clean the air in rooms other than the one they are placed in.
If you have more air purifiers than is necessary, you do stand the chance of over-purifying the air in your home and using more energy than necessary.
Do not forget about the height of the position of the purifier. Specialists recommend placing the device on the floor, because it is near the ground that there is a higher concentration of pollutants. Setting it on a shelf can significantly reduce the filtration efficiency.
Damage to the HVAC System
Reduced Efficiency of the System: An improperly sized air filter can create an imbalance in the airflow, which means the system may not operate at its designed efficiency. When the HVAC unit is forced to work harder, it consumes more energy, leading to increased utility bills.
Some ideal places to keep the air purifier within the bedroom are near your bed, on a nightstand, or mounted onto a high shelf; this will maximize the elevation and ensure an equal amount of fresh air distribution throughout the room.
In theory, you would get the best results by having an air purifier in every room of your home. However, the cost of doing this can make it impossible for most people. If you're wondering whether you need an air purifier for each room, start with an affordable two: one for your bedroom and one for the living area.
Choose a Central Location
Place your air purifier in a central area of the room to allow for efficient airflow and circulation. This means you should keep your device away from walls, corners, and other obstructions (more on why in a second).
Mold is an obvious health risk in any home, but investing in an air purifier can help limit your exposure. The best among them will ideally offer HEPA-level filtration, with this level of filtration being able to trap up to 99.97% of airborne particles down to 0.3 microns in diameter.
Since air will flow wherever there is an opening, the air purifier will try to pull in air from outside if doors are not fully closed.
The Blue Pure Mini Max is our pick if you're looking for an air purifier for a small room on a decently low budget. If you have a small bedroom or office, this could be all the air purifying power you really need.
Most air purifiers consume between 30 and 250 watts of electricity, with the average unit using around 50 watts. To put this into perspective, a typical 60-watt incandescent light bulb uses more energy than many air purifiers.
Typically, a high-quality air purifier like those from Alen can start showing noticeable air quality improvements within 30 to 60 minutes. However, achieving optimal results throughout your entire space can take several hours, depending on the conditions.
A purifier that's too small may struggle to adequately clean the air in larger spaces, while one that's too powerful for a small room could be unnecessarily loud and consume more energy than needed. Let's not forget, different types of rooms have different air purification needs depending on what happens in them.
What are the downsides of air purifiers? There aren't a lot of downsides to having an air purifier in your home aside from the financial investment. Many ionizers, especially older models, can generate ozone when they are operating, which is known to exacerbate asthma.
It's perfectly safe to keep the device running continuously, and the amount of energy it consumes is very small.
Oversized is better than undersized
Purifiers rated for spaces larger than the one you plan to use them in can operate at lower, quieter speeds. All our picks are sufficiently oversized that running them on their quieter medium settings will keep the air clear in the rooms they're sized for.
While you can technically use a different size air filter, it's not recommended. An ill-fitting filter can allow unfiltered air to pass, reducing your system's efficiency and potentially causing damage.
If the air filter is too large, it will cause the system to run slowly and reduce the efficiency of the filtration process.
While air purifiers are effective at removing the majority of the offending allergens from a single room, they do not take away all the airborne particles, Dr. Alana Biggers-Walker, associate professor of medicine at the University of Illinois Chicago, told Live Science.
In principle, installing a ventilation system and/or an air purifier will relieve you of the need to air your home, but an additional supply of fresh air may still be useful in some cases: When you have just used paint, glue or other chemicals in your home.
Pollutants like smoke, pollen, and certain allergens tend to float higher up, making a ground-level purifier less effective in combating them. Additionally, putting your air purifier on the floor can mean it's more likely to encounter obstructions, like furniture or household items.