The reason I was thinking of going to MERV 10 is because the MERV 8s are not
capturing visible dust.

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Thanks.


"RickH" wrote in message
ps.com...
On Aug 27, 5:40 pm, "Saucer Man" wrote:
I have 3 returns in my house. I was told that I do not need an air
filter
in my main unit (which is in my attic) if I have a filter in the returns.
However, when I had a filter in the main unit, I noticed it was
dirty....even though I had filters in all the returns. So currently, I
replace all 4 filters regularly. Is this ok? I use MERV 8 pleated
filters.

I want to start using MERV 10 filters. Is it okay to still use one in
the
main unit?

--

Thanks.

I like MERV8 as a good compromise between cost, back pressure, and
particle size. MERV8 is usually the most porous of the widely
available paper pleated types and will stop most pollen and all
visible dust. Pollen is my main concern (due to hay fever) and they
do a good job. The next smallest particle filter practically doubles
in price, and causes over twice the back pressure but the extra dust
it captures is not worth the price or backpressure IMO. The next
filter down is usually a fiberglass pad that has little back pressure
and is cheap but doesn't catch most visible dust and no pollen. An
alternative would be to use a cheap pad filter on the ducts and a
MERV8 on the air handler, this will keep the big "dust bunnies" out at
the beginning so the MERV8 only has to do the pollen and small dust at
the fan.