You should only have one air filter in any air stream. Otherwise you are
severely restricting the air flow and can burn out any air-cooled blower
motor.

"newsreader" wrote in message
...
I'm in the same situation. My household includes 3 dogs & 2 cats, which
I'm
sure adds to the dust load. DW vacuums religiously with our central vac,
got
a 3M Filtrete in the downstairs air handler, & 3 more Filtrete filters in
the upstairs return air intakes. I bought a couple Bemiss Console
Humidifiers, which include an air filter, about a month ago. They don't
seem
to be doing anything for the dust, but the moister air certainly makes the
house more comfortable.

After browsing more air filter sites than I can count, I ordered a
Friedrich
C-90B Electronic Air Cleaner.


http://www.berriman-usa.com/pdf_broc...s_brochure.pdf


From what I read, it seemed like it might do a decent job without having
to
spend major bucks regularly on replacement filters. Unfortunately, I'm
still waiting for it to get here. Ordered on Jan 22 from the least
expensive
online shop I could find. Probably a dumb thing to do.

Looking forward to hear what others here have to say.

David