Paul Franklin wrote:
On Fri, 07 Dec 2007 03:43:09 GMT, wrote:

snip
Filters like that Trion actually filter better as they get dirty
because the accumulated soil reduces the size of the pores in the
filter media. You are better off not changing it too often. Also, the
big pleated filters are quite expensive. The best way to determine
when it needs to be changed is to check the pressure drop across the
filter, and you can get devices to do this. One simple one is just a
whistle that starts making noise when the pressure drop across the
filter rises. On the other hand, if you don't change when it is truly
dirty, your airflow will be restricted too much and the furnace
overtemp sensor may shut the furnace down.

I'd set the thermostat timer to work out to about a month in prime
heating or cooling season and use its alarm as a reminder to *check*
the filter. If the pleats are uniformly gray and there is a
noticeable layer of dirt, then change it. Otherwise, reset the alarm
and check a month later when it goes off again.

My $0.02

Paul F.



Sounds like some kind of special filter system. I've googled and can't
find any info on this particular one. Can you give a description of how
this works and how it is different from a normal slab filter?

http://www.fedders.com/catalog/residential/airbear.htm

or google "trion air bear filter"

Honeywell makes a similar media type filter. They are designed to
compete with electrostatic air cleaners without generating ozone.
They are also cheaper to purchase and install initially than
electrostatics, but media replacement costs over time are much higher,
since electrostatics are just cleaned in the dishwasher.

The media cartridge is about 6 inches thick, with accordion bellows
shaped media with thick folds. This gives it a lot of surface area so
the pores in the media can be made smaller to filter better without
restricting the air flow too much.

Paul F.


Well now. That's a horse of a different color.