4 Reasons not to buy an electrostatic air filter

Disadvantages of electrostatic air filters (a.k.a. electrostatic precipitator air cleaners):
1. Can cause furnace problems.
Electrostatic air filters are too dense for most furnaces. As a result, they can interfere with the airflow of the furnace, causing the air conditioner to freeze up in the summer. Electrostatic air filters can also cause the furnace to overheat in the winter.
2. Maintenance.
Electrostatic air filters require frequent cleaning, usually more than once a month. They cannot just be installed and forgotton about. Unfortunately, they usually are neglected. Most people simply do not remember to get inside the furnace at least once a month, clean the filter, then re-install it. Even if you did, this routine is still a pain, due to the fact that electrostatic air filters usually have several layers you have to remove and clean individually.
3. Effectiveness.
The problem with electrostatic and all other air filters is that they can only remove the larger airborne particulates. What they fail to mention is that most airborne pollutants are smaller than the 0.3 microns that they are capable of removing. Allergens, toxins from cigarette smoke, etc. still manage to slip these screens, and back into the air we breathe.
4. Black Wall Effect
Electrostatic air filters work by electrically charging particles so they are attracted to the metal plates in the machine. However, these charged particles are also attracted to all surfaces, resulting in black markings on walls, etc.
If an electrostatic filter is not the solution, then what is?
For an in-depth look at air purifiers, see the Air Filter (not electrostatic) / Air Purifier Buying Guide.
IPS Negative Ion and Ozone Air Purifier Products