Washable Air Filters

[DavidPJ]

After reading the posts here regarding air filters and air flow, I would like to replace my 3M Filtrete "purple 1250" air filters with filters with a Merv 8 rating. I checked Lowe's today, and although they carry Flanders, it's their very basic model that doesn't even show the Merv rating. It looks like I can special order the other Flanders filters.

I also saw Web washable filters that carried a Merv 8 rating. They also have a Web filter that is adjustable that will adjust to every size I need but one. They appear to be built well. Just wondering what your thoughts are on the Web Merv 8 washable filters.

Thanks for your comments.

[gary_g]

Home Depot has NaturalAire Standard pleated filters made by Flanders. MERV 8. A 3-pack is less than $10.

[HydroAirJoe]

After reading the posts here regarding air filters and air flow, I would like to replace my 3M Filtrete "purple 1250" air filters with filters with a Merv 8 rating. I checked Lowe's today, and although they carry Flanders, it's their very basic model that doesn't even show the Merv rating. It looks like I can special order the other Flanders filters.

I also saw Web washable filters that carried a Merv 8 rating. They also have a Web filter that is adjustable that will adjust to every size I need but one. They appear to be built well. Just wondering what your thoughts are on the Web Merv 8 washable filters.

Thanks for your comments.

Why do you want to replace the 1250? Coast?. The Ultra 1250 is only sightly more restrictive than many Merv 8 filters, so if you are doing this to drop the static pressure, going to a Merv 8 filter may not give the gains your system needs.

[DavidPJ]

My 1250s are beginning to load up so I'm beginning to look at replacing them. And I'm looking at the Flanders filters because they were mentioned favorably here for reasons of little drop in static pressure and cost.

Thanks gary g for telling me where to find the NaturalAire Merc 8 filters.

I still like the idea of a reusable and washable filter for both long term cost and environmental reasons. But, I would like to know if anyone has tried the Web filters before rushing out to buy them.

[bigbooty]

Why do you want to replace the 1250? Coast?. The Ultra 1250 is only sightly more restrictive than many Merv 8 filters, so if you are doing this to drop the static pressure, going to a Merv 8 filter may not give the gains your system needs.

Wow, Joe.......

You obviously haven't read many filter threads around here.

I'm going to go pop some popcorn and see how interesting this thread will get.

[samtheman]

Home Depot has NaturalAire Standard pleated filters made by Flanders. MERV 8. A 3-pack is less than $10.

i use these filters in my own house. better value than the washables. I awlays tell my customers not to use the filtrete filters, most systems cannot handle them

[aintitfun]

DO NOT , and I repeat DO NOT, buy the washable/lifetime filters of any kind. You will only make your situation worse. Please, I am begging, for your system, dont do it!!!!

[Kevin O'Neill]

I agree. Many of the washable filters are worse than the 3M Filtretes, when it comes to air flow resistance.

[johnt2_2002]

I agree. Many of the washable filters are worse than the 3M Filtretes, when it comes to air flow resistance.

Dont get either washable or use the purple 3M filters!! Like stated, they will cause more problems than good!!

if anything, I would downgrade to the 3M filters that are in the red cardboard(not sure of it rating tho) or the Merv 8's...

[DavidPJ]

I bought the Flanders Merv 8 filters at Home Depot today and they work great and the price was right. I noticed improved air flow at the returns after replacing the 1-2 month old 3M 1250s. The 3Ms were not visibly dirty.

Thanks everyone for the education.

[Indigo]

Why would you want to switch from Filtrete when its doing exactly what it's supposed to do - take particles out of the air? You are getting improved indoor air quality and protecting the equipment and helping it operate more efficiently. Your filter simply needs to be changed more often - you'll have better air and save money.

[samtheman]

Why would you want to switch from Filtrete when its doing exactly what it's supposed to do - take particles out of the air? You are getting improved indoor air quality and protecting the equipment and helping it operate more efficiently. Your filter simply needs to be changed more often - you'll have better air and save money.

the greatly reduced airflow does not help the unit operate more efficiently and can cause damage to the system. The purpose of the air filter is to protect the equipment, not to clean the air

[neophytes serendipity]

After reading the posts here regarding air filters and air flow, I would like to replace my 3M Filtrete "purple 1250" air filters with filters with a Merv 8 rating. I checked Lowe's today, and although they carry Flanders, it's their very basic model that doesn't even show the Merv rating. It looks like I can special order the other Flanders filters.

I also saw Web washable filters that carried a Merv 8 rating. They also have a Web filter that is adjustable that will adjust to every size I need but one. They appear to be built well. Just wondering what your thoughts are on the Web Merv 8 washable filters.

Thanks for your comments.

Don't do it.

Stick with plain old fiberglass non-pleated air filters.

If you *need* better filtered air, put something in that will work right. Odds are, that means you will have to call someone out to make changes to the return ducting at the furnace at a minimum.

Slapping a 1" pleated filter into an existing residential system never works right.

[Kevin O'Neill]

Don't do it.

Stick with plain old fiberglass non-pleated air filters.

If you *need* better filtered air, put something in that will work right. Odds are, that means you will have to call someone out to make changes to the return ducting at the furnace at a minimum.

Slapping a 1" pleated filter into an existing residential system never works right.

You got that right!

[Indigo]

Originally Posted by Indigo
Why would you want to switch from Filtrete when its doing exactly what it's supposed to do - take particles out of the air? You are getting improved indoor air quality and protecting the equipment and helping it operate more efficiently. Your filter simply needs to be changed more often - you'll have better air and save money.

the greatly reduced airflow does not help the unit operate more efficiently and can cause damage to the system. The purpose of the air filter is to protect the equipment, not to clean the air


Actually the purpose of the air filter is indeed to improve air quality, as well as assist the equipment in operating more efficiently. This is true commercially and residentially. If there is greatly reduced air flow it's time to change the filter! This is beneficial to the equipment too, as well as the IAQ. Putting in a cheap low-MERV filter allows more particles to accumulate on the system making it run less efficiently, and reduces the IAQ. The days of filters merely protecting equipment are long-gone, and the sooner we as an industry get our arms around it the better.

[dandar]

The purpose of the air filter is to protect the equipment, not to clean the air

Care to elaborate on that statement? Why can't it do both? Why shouldn't it do both?

[samtheman]

[SIZE="2"]Originally Posted by Indigo
If there is greatly reduced air flow it's time to change the filter!.

put a new 3m purple filter in a system and measure the static pressure, delta T, or superheat and compare to a standard filter.

An air filter protects the equipment, an air cleaner improves IAQ

[meBNme]

fiberglass!?!?

and all IAQ specialists groan in pain from coast to coast.




Fiberglass shmiberglass......... dang things might catch a screwdriver it you throw one at it, but what.... 80 of the dust in the air goes right through em only to collect on the evap coil and blower fins?

But hey, then the customer needs to buy a UV light to kill the moldy cantamination on the coil that grew off the dust buildup..... and they eagerly purchace the maintenance agreement to have all that contamination and dust cleaned off every year.

those fiberglass things are what..... 8 % efficient?

[samtheman]

Care to elaborate on that statement? Why can't it do both? Why shouldn't it do both?

it can do both, but you won't achieve the results you are looking for by merely removing a standard 1" filter and sticking a "high efficiency'" 1" filter in its place

[Kevin O'Neill]

Originally Posted by Indigo
Why would you want to switch from Filtrete when its doing exactly what it's supposed to do - take particles out of the air? You are getting improved indoor air quality and protecting the equipment and helping it operate more efficiently. Your filter simply needs to be changed more often - you'll have better air and save money.

the greatly reduced airflow does not help the unit operate more efficiently and can cause damage to the system. The purpose of the air filter is to protect the equipment, not to clean the air


Actually the purpose of the air filter is indeed to improve air quality, as well as assist the equipment in operating more efficiently. This is true commercially and residentially. If there is greatly reduced air flow it's time to change the filter! This is beneficial to the equipment too, as well as the IAQ. Putting in a cheap low-MERV filter allows more particles to accumulate on the system making it run less efficiently, and reduces the IAQ. The days of filters merely protecting equipment are long-gone, and the sooner we as an industry get our arms around it the better.

A little bit of knowledge is a dangerous thing. The typical 1" pleat has 2.5 times the resistance to air flow of a standard 1" fiberglass filter. If your system has not been designed to handle that restriction, don't install the pleat!

[Kevin O'Neill]

See This Attachment....Uploaded in 3 parts to get past the file size limit. It saves retyping the whole article.

[Indigo]

A little bit of knowledge is a dangerous thing. The typical 1" pleat has 2.5 times the resistance to air flow of a standard 1" fiberglass filter. If your system has not been designed to handle that restriction, don't install the pleat!

That's certainly true, because a 1" fiberglass filter does nothing more than take out rocks and sticks. There is no system in operation today that cannot operate with, and benefit from, a 1" pleat, as long as its changed out per the recommendations.

Filters come in a variety of MERV ratings because they DO improve IAQ and don't just protect equipment. Although Filtrete doesn't put MERV ratings on their residential filters (they should!) there's a reason they have different grades, with called Micro-allergen, Ultra-Allergen, etc.: they're improving IAQ!

Filters are not a 'necessary evil'. They provide a benefit, for your equipment, and your customer's air quality. Why would you not want to be looked upon as their air quality expert and not just their mechanical contractor? It's a tremendous opportunity for your business.

[Kevin O'Neill]

Do you have the instruments needed to measure air flow? Do you have the instruments needed to measure pressure drop across filters? Do you use those instruments? If not, then you should be careful about the uninformed statements that you make. I measure air flow and air pressure drop almost every day. 1" Pleated air filters do more harm than good in most cases. Read the article I uploaded for more information.

If you are not measuring, you are just guessing.
-Rob Falk, National Comfort Institute

[samtheman]

That's certainly true, because a 1" fiberglass filter does nothing more than take out rocks and sticks. There is no system in operation today that cannot operate with, and benefit from, a 1" pleat, as long as its changed out per the recommendations.

.

Are you aware that HVAC air handling equipment is engineered to have a certain volume of air flowing though it? That a restrictive filter will reduce the volume of airflow and affect the performance of the system, sometimes to the point of doing damage?

I have seen plenty of cooling systems that could not meet demand simply because a filter that was too restrictive was installed. It is a simple matter to test this if you have the proper equipment and knowledge.

[meBNme]

So the pleated filter is slightly more restrictive than the fiber. The fiber is slightly mroe restrictive than no filter, big deal. The question is not "is the pleated filter more restrictive?"

The question is. does it matter?

Systems are desighned to operate with some restriction, so the question is how much?

so the pleated 65% filter is slightly more restrictive than the fiber 6% filter.

Your point is? Can the system really not handle the slight drop considering it is desighned for some restriction in the first place?

With all the modern efficiencies and indoor air quality products, are you saying that all those units just cant handle anything more than a fiber filter?

So obviosly, measurements are neccesary.

But is there a mistake being made here?

Are we measuring the drop in airflow and saying "Yep, its dropping mor ewith the pleated than the fiber, so the pleated is bad, remove it."
When instead we should be saying, "sure, there is more resistance, but what can the system truley handle? Is that increased restriction more than the unit can handle?"

Sure, we have all seen abuseive filtration systems and dirty clogged filters. But thats true with ALL filters including the fiber ones.

[Kevin O'Neill]

So the pleated filter is slightly more restrictive than the fiber. The fiber is slightly mroe restrictive than no filter, big deal. The question is not "is the pleated filter more restrictive?"

The question is. does it matter? YES

Systems are desighned to operate with some restriction, so the question is how much? It depends on the equipment and ducts. Many systems do not deliver the correct air flow even with just a cheap fiberglass air filter installed. Half of the systems I have measured over the last 20 years are running at 50% of required air flow or less.
so the pleated 65% filter is slightly more restrictive than the fiber 6% filter. It is WAY more restrictive than the 6% filter. By the way, the fiberglass filter is probably only about 3% efficient. It is there to protect the equipment, not improve air quality. For that you need a duct mounted filter, properly installed and TESTED!
Your point is? Can the system really not handle the slight drop considering it is desighned for some restriction in the first place? Usually not.
With all the modern efficiencies and indoor air quality products, are you saying that all those units just cant handle anything more than a fiber filter?

That is generally the case. Many times even the fiberglass filter is too restrictive because of poor system design.

[meBNme]

That is generally the case. Many times even the fiberglass filter is too restrictive because of poor system design.

ahhhggg.... you caught me in the middle of an edit. sorry.

Please revisit my post. I value your opinions on it.

[meBNme]

Also, have you tested the different results between 1 inch pleated filters and 5 inch duct mounted ones like say.... the aprilaire or honeywell media filters?

[Kevin O'Neill]

Yes. The Aprilaire is the way to go.

[Kevin O'Neill]

The 6-inch duct mounted filter listed at the bottom of the table is the Aprilaire Space-guard 2200. Up to 3 tons it is just fine. Systems larger than 3 tons should usually have 2 installed in parallel.

[meBNme]

Yeah, thats what I sell is the the AA 2210 and 2410 (as well as the 4000 and 5000 series) But while I know they are better in every way and have seen the results. I honestly have not seen test results with direct comparison to the competing filtration systems or to any 1 inch filters in regards to restrictiveness, and more importantly, what the systems are desighned to handle.

[Kevin O'Neill]

I believe the Aprilaire 2200 is MERV 12. Pressure drops listed in "Table 1" in the article. One of the 1" pleats was a 3M, red package.