Home hvac Air Filters: Flat panel or pleated?

JEDI

Lifer
Sep 25, 2001
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I used to buy fiberglass air filters for my home's central air (4 for $1.50) but walmart doesn't carry them anymore. :(

cheapest now is a basic flat panel filter $2 each.
next cheapest is pleated @ $3 each.

Which is better?
 

Red Squirrel

No Lifer
May 24, 2003
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www.anyf.ca
The thicker pleated ones filter better, but they restrict air flow more too. Try one and see how it goes. I tried one on my furnace and blower was rattling a lot due to not enough air flow. (it actually spins faster).

Large commercial units tend to use filters like that. Some are actually like 3 inches thick.
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
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I'm not positive, but I think the electrostatic filters are supposed to give you the filtering of the pleated, without the reduced air flow that pleated results in. Those spun fiberglass filters are all but useless for reducing dust in the house. But that's it right there - if you don't have an issue with dust, why filter out what doesn't need to be filtered? Just a couple weeks ago, I finally convinced my wife to just put a box fan in our central room of the house, and leave it running - I placed a pleated filter behind it. The air flow (pressure difference + friction) holds it in place. After just a week, my wife was amazed at how much dust it captured; the filter is filthy. (Some remodeling work going on; lots of dust had been created.) And, my wife is commenting on how much less dust is on the furniture. It didn't have to be changed, but she already went out and bought 3 or 4 more filters, and changed the filter. I'm planning on testing out the electrostatic filters once summer rolls around and more air circulation would be nice.
 

cbrsurfr

Golden Member
Jul 15, 2000
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Unless you have allergies just use the fiberglass ones. Any home improvement store will have them for 50-99 cents each. I just buy them by the case for <$10.

My coworker pays like 6 bucks each on Amazon for filters because he's anti-social and won't go to a home improvement store.
 

JEDI

Lifer
Sep 25, 2001
30,160
3,300
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I'm not positive, but I think the electrostatic filters are supposed to give you the filtering of the pleated, without the reduced air flow that pleated results in. Those spun fiberglass filters are all but useless for reducing dust in the house. But that's it right there - if you don't have an issue with dust, why filter out what doesn't need to be filtered? Just a couple weeks ago, I finally convinced my wife to just put a box fan in our central room of the house, and leave it running - I placed a pleated filter behind it. The air flow (pressure difference + friction) holds it in place. After just a week, my wife was amazed at how much dust it captured; the filter is filthy. (Some remodeling work going on; lots of dust had been created.) And, my wife is commenting on how much less dust is on the furniture. It didn't have to be changed, but she already went out and bought 3 or 4 more filters, and changed the filter. I'm planning on testing out the electrostatic filters once summer rolls around and more air circulation would be nice.
I'm thinking the electro static ones are a bit more expensive than the 2 types I listed in my OP.
and what does the spun fiberglass filter out then?


Unless you have allergies just use the fiberglass ones. Any home improvement store will have them for 50-99 cents each. I just buy them by the case for <$10.
lowes/home depot doesn't have fiberglass filters either :(
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
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and what does the spun fiberglass filter out then?
Tennis balls.

The fiberglass ones are nice because you can run them for a long time without them getting dirty. That's because a very high percentage of the dust passes right through them. (75%, if I recall correctly.)

There's also an electrostatic one that's washable - it's even more expensive, but provided regular maintenance, can last you 5 or 6 years.
 
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cbrsurfr

Golden Member
Jul 15, 2000
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I'm thinking the electro static ones are a bit more expensive than the 2 types I listed in my OP.
and what does the spun fiberglass filter out then?

lowes/home depot doesn't have fiberglass filters either :(

Do you live in a communist state that has banned them or something? Could be BS but the guy who installed my HE furnace said not to use the pleated as they cause the fan to work harder.
 

gorcorps

aka Brandon
Jul 18, 2004
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Do you live in a communist state that has banned them or something? Could be BS but the guy who installed my HE furnace said not to use the pleated as they cause the fan to work harder.

There's some truth to that. It gets even worse if you get the fancy allergen controlling ones and try to force your HVAC system to be an air purifier. Use an actual air purifier for that and don't put that load on your HVAC system.
 

RagingBITCH

Lifer
Sep 27, 2003
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There's some truth to that. It gets even worse if you get the fancy allergen controlling ones and try to force your HVAC system to be an air purifier. Use an actual air purifier for that and don't put that load on your HVAC system.

Always to an extent. Looking at the MERV rating as well - the higher (which filters more) the lower velocity of air that goes through. I'd never put a MERV2 or a MERV18 (if they make either or) in my systems...the ones I normally get around around mid-range. (8) Considering we just got done w/ a kitchen reno and I changed both filters - the thing was completely grey and caked in dust.
 

MadScientist

Platinum Member
Jul 15, 2001
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