- In this report
- Overview
- Features
- How to choose
- Purifier types
- Improving your air quality
- Ozone generators
- Electrostatic precipitators
- CR Quick Recommendations
- Room models
- Whole-house models
- Ratings
- Room models
- Whole-house models
APPLIANCES FORUMS  Discuss and learn about appliances for the kitchen, laundry, and other rooms in the house. |
Important features Air cleaners
Whole-house air filters generally include a range of standard sizes, with some that adapt to fit different-size filter-box or return-air openings. Room air cleaners usually use a fan to pull air into the unit for filtration. Some with an electronic precipitator or a HEPA filter include ionizing circuitry that uses powered needles or wires to charge particles so that they are more easily trapped by the oppositely charged filter. But this ionization may also make the particles stick to walls or furnishings, possibly soiling them. An indicator in most models lets you know when to change or clean the filter.
HEPA filters must typically be replaced annually and can cost $200 or more, sometimes approaching the cost of the air cleaner itself. Prefilters, which are designed to remove larger particles, are generally changed quarterly, while washable prefilters should be cleaned monthly. An electronic precipitator's collector-plate assembly must be removed and washed every month or so; you can do it in the sink or put it in a dishwasher. Most room models have a handle, while some heavier models have wheels. Fan speeds are usually low, medium, and high. A few use a dust sensor and an air-quality monitor designed to raise or lower the fan speed automatically. But we found these sensors didn't kick in until levels were high, then shut off before levels dropped sufficiently.
Whole-house air filters generally include a range of standard sizes, with some that adapt to fit different-size filter-box or return-air openings. Room air cleaners usually use a fan to pull air into the unit for filtration. Some with an electronic precipitator or a HEPA filter include ionizing circuitry that uses powered needles or wires to charge particles so that they are more easily trapped by the oppositely charged filter. But this ionization may also make the particles stick to walls or furnishings, possibly soiling them. An indicator in most models lets you know when to change or clean the filter.
HEPA filters must typically be replaced annually and can cost $200 or more, sometimes approaching the cost of the air cleaner itself. Prefilters, which are designed to remove larger particles, are generally changed quarterly, while washable prefilters should be cleaned monthly. An electronic precipitator's collector-plate assembly must be removed and washed every month or so; you can do it in the sink or put it in a dishwasher. Most room models have a handle, while some heavier models have wheels. Fan speeds are usually low, medium, and high. A few use a dust sensor and an air-quality monitor designed to raise or lower the fan speed automatically. But we found these sensors didn't kick in until levels were high, then shut off before levels dropped sufficiently.
