Home Air filters (AC/Heater)

[DallasTexasEx]

Any experts out there on home air filters? I typically buy the cheap ones at Home depot, but since our kids are developing allergies, I am considering buying the more expensive 3M filters or something similar. Are the more expensive ones really that much better? Also, anyone know of a website to order the expensive ones at a discount price?

Any info would be appreciated.

Thanks.

 

[GhostOfTomJoad]

Definitely use the 3M Filtrete versions. I use the Ultra-Allergen (purple packaging) myself as my wife is very sensitive to allergens. I've recently seen 2 packs of them @ Costco but only in a few of the more common sizes (fortunately one was our size). It was like $25 for 2 which was a pretty good deal.

 

[I Am Texas]

The Filtrete type filters do a pretty good job of trapping allergens, but are not so good for your AC/Heater. They will cause your unit to work much harder/less efficiently, as they restrict the air flow much like a clogged cheap filter would. They can even cause the unit to completely ice over in the summer time...

 

[14tokihorn]

For my next purchase, I've bookmarked this-The Link

Haven't priced the stores lately, but may just order them to save some coin... they carry all the 3M filters as well as others.

 

[GhostOfTomJoad]

In reply to:

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[I Am Texas]

I couldn't disagree w/ this more, & in fact when I had a brand new HVAC system installed in October one of the first things I was told by the installers was to invest in high quality filters like Filtrete. The 3M filters aren't so much thicker (we're talking microns) that they'll strain a system. Filtrete's advantage is the electrostatically charged particles that pull the allergens from the air. What the HVAC techs told me is that high quality filters trap a large amount of the dust & crap that would otherwise eventually work its way into the motor housing inside the blower unit thereby causing it to run less efficiently. A good filter is not going to cause your AC unit to freeze up. I just spent 7 grand on my system & the 2 tips the guys gave me were to keep the outside AC unit clean & use high quality filters on the furnace.

Ha! Go remove that Filtrete filter and see how much more is pushed through your registers.

 

[brntorng]

The best quality Filtrete filters are very effective. However, they do restrict air flow just like all filters. The question is whether it's excessive. The answer is it depends on the design of your HVAC system. The only way to know for sure is to measure the air pressure drop across the filter with a manometer (they're cheap). Chances are if you replace the Filtrete filter 4 times a year you'll be fine. Better yet, if your thermostat monitors HVAC run time it will tell you when it's time to replace the filter since it varies by season.

If an HVAC tech is really on top of it, they will recommend a 4" filter canister rather than the 1" 3M filters. 4" filters can be just as effective as the Filtretes and typically only need to be replaced annually. Also, since they have much more filter surface area they don't restrict air flow nearly as much as 1" filters.

 

[Seattle Husker]

Anyone know of a good site to buy the 4" filters? They are ~$25-$40 (each) at Home Depot. We change ours every 3-4 months (I have 3 young sons and a dog) so I'd love to find a cheap site to buy from.

That filtera site only carries the 1" filters.

 

[brntorng]

I order my 4" filters from Shorty.