What is an Ionizer? (by 2 users)

Some Air Purifiers have an independently controlled ionizer, which, when turned on, releases negative ions into outgoing filtered air. Ions are tiny particles that carry a positive or negative charge. These ions exist naturally around us, in the air, water and ground. Both positive and negative ions are colorless, odorless and completely harmless. Negative ions help the air purification process by attaching themselves to very small airborne particles in the room.
These particles take on a negative charge and may join with positively charged particles such as dust, pollen, smoke and pet dander to form larger particles that are then more readily captured by the filter system, or may be attracted to positively charged surfaces throughout the home, like walls or floors. This may occur more frequently when the filter is nearing the end of its functional life expectancy and is able to capture less of the charged particles.
You may also note after extended use, that dust may have collected around the grills or front panel. This is from the ionization affect caused by the negative ions exiting from the air outlet. This is additional evidence of the air cleaning effectiveness of negative ions. The dust can be easily removed with a clean, damp cloth or soft brush.
Finally, using your ionizer may result in an occasional popping or cracking sound. This is a normal sound, generally caused by particles of dust that are interrupting the flow of ions, causing a small build-up of ions that, when discharged, cause the popping or cracking sound.
NOTE: It is important to replace the HEPA filter at the recommended intervals.
Using the ionizer in conjunction with dirty filters may result in dirty particles exiting the air purifier and being attracted to walls, carpets, furniture or other household objects. These dirty particles may prove very difficult to remove. Homes with excessive amounts of pet dander, dust, or smoke may decrease the life expectancy of the HEPA filtration system. You may want to run the Ionizer less often and check the condition of the HEPA filter(s) more frequently.
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