How to Choose a Filter for Healthy Home HVAC: Capturing Particles vs. Chemicals with Aprilaire

Explained using the three most available high quality filter types (MERV 11, 13 and 16), I offer a quick tour through the size range of the invisible stuff you don't want to breathe. The black carbon filter is an Aprilaire 213CBN (shop.aprilaire.com/collection....
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[@geraldhenrickson7472]

It is worth mentioning that the original reason for a HVAC filter was to protect the equipment. Even a MERV 5 today will do this just fine. If you want to make you indoor air healthy for humans...be sure your HVAC system can handle the additional back pressure created by a high MERV rating. Consider going to a 4-5" thick filter to preserve what airflow your heating system is capable of. The AprilAire filter system shown here is a good one. Thanks for the video.

[@joeshmoe7899]

Got the "fan on" set on my central air, 24/7. With merv 8, it is reducing 0.5 micron particles by 75% or more from outside air. Measured with Dylos particle counter. Ventilating so that 3 adults never go higher than 900 ppm co2. Typically 800ppm co2.

[@vanhalenman60]

i love those april air filters. they have the best seal around the edges from what ive used over time.

[@HomePerformance]

Agreed

[@briansantistevan1026]

I live in a mobile home, the heater/ac is electric. I also have several birds in my home. What is the best filter for the situation?

[@dannyg751]

Can you explain why we shouldn’t buy ionizers? I don’t keep up with the modern research or testing on them

[@cemprotecta]

Thanks. Quite informative. Do you think such filters can cope with graphene nanoparticles?

[@abel5925]

Im using a 4 inch deep Merv 13 filter, 1 IQair system and an extra 4 hepa filters in rooms. The house is small 1400 sqft. I took this approach due to your videos a few years ago, my asthma is su much better. My dream setup is a hepa filter but that’ll have to wait

[@HomePerformance]

Great to hear, Abe!!!

[@abel5925]

@@HomePerformance thanks! I may get one of these filter systems shown in the video. The surface area looks great.

[@dianeibsen5994]

There are many choices one can make re. The house hold products used in our homes. especially washers/dryers. The EPA does not regulate the toxins coming from scented, lab-made chemicals..ie dryer sheets, Tide, plug in "air fresheners" febreeze etc🙏🌎🌸🌿

[@lee-johnson]

People should be careful going too high on the MERV scale. Many HVAC systems were not designed to move enough air flow due to filter grille sizes. I’ve seen many systems iced up due to poor air flow from high efficiency filters. The higher the MERV, the higher the pressure drop. Great video

[@HomePerformance]

Absolutely, Lee. Partly why I used the Aprilaire filter caninet for this example, rather than a set of filters that could feasibly be crammed in there.

[@jefflebowski918]

That's true, most HVAC systems work best with a 8 MERV/ 5 FPR filter. Some newer HVAC systems can handle higher MERV/FPR filters.

[@HomePerformance]

Dude

[@oldmech619]

Higher the filter number, the harder the blower works. That’s costing you money. Also, it will burn out your motor sooner. I just had to buy a new motor.

[@HomePerformance]

That’s why we upsize the filter, or turn it on the diagonal.

[@Mystprism]

Hi Corbett, it's my understanding that those pleated filters that are "carbon infused" simply don't contain enough carbon mass to effectively eliminate chemicals for any sort of extended time. Do you have any research or data contrasting pleated carbon filters to something that contains larger carbon pellets in a thicker kind of honeycomb structure? Or more broadly, is there any sort of certification for carbon filter effectiveness?

[@HomePerformance]

You will love the video coming soon on wildfire effects- you’ll get your answer then

[@thebigdoghimself]

What about UV lights? I have a Honeywell unit in each of my mitsubishi air handlers. Also can most hvac units deal with the resistance of merv 16 filters?

[@HomePerformance]

If the filter has enough surface area, a cheapo air handler could handle a MERV 1000. Surface area and pressure drop is the thing to aim for.

[@HomePerformance]

Also, IF the UV light is only for prohibiting growth on the coil itself, that’s fine. Anyone trying to sell you on disinfecting the AIR is selling snake oil.

[@carlwindnagle6194]

How do you know if your furnace blower will still work ok with a higher MERV level filter? Don't the higher MERV levels create more back pressure?

[@HomePerformance]

Yes they do- but filter manufacturers calculate the pressure drop of each of their filters- you can find those tables published.

[@shelbytollett7119]

Air purity meters, i know you were testing different meters, have you changed which ones you use now?

[@HomePerformance]

Right now I’m mostly interested in our Airthings Wave Plus.

[@WayneSleight]

Thank you for this video, Corbett. Would you consider the Air Scrubber by Aerus (the model that does NOT produce ozone) as one of those devices to stay away from?

[@HomePerformance]

YES, Wayne, I would 100% advise avoiding anything that sprays disinfecting chemicals ‘into every nook and cranny’ of your home, as they claim. Chemistry is what they’re using as the solution there, and they cannot possibly predict the side effects since they don’t know what chemicals are in your home to start with.

[@WayneSleight]

@@HomePerformance I greatly appreciate your answer!

[@cupbowlspoonforkknif]

You teased ozone and now I want to learn more! Do you have a video on it?

[@HomePerformance]

kzbin.info/www/bejne/n3XdlZ-qbtqZjc0

[@stevepailet8258]

Around here with my leaky house. The little bit of carpet does a fair amount of filtering LOL. Because this house is almost as old as dirt I only keep a pleated filter in the AC to semi keep the coil clean. Wish I had a place tight enough that a chemical filter would be effective. Now going out on a limb. Figure most houses built even today still would not find a chemical filter worthwhile. With all the crazy KEMIKALs people introduce into homes, we need them. Dealing with the fines I have working doing sharpening At most I only go down to .025 micron particles. I could deal with a nice fan in my van with a merv 16 to really cut down on the metal flying. So lacking that I keep the doors open and let the air blow thru

[@dianeibsen5994]

A regular fan in your van or filter?

[@stevepailet8258]

@@dianeibsen5994 just a fan in a box where I could put a real merv filter would be nice but all I have is a $10 12 volt plug in fan

[@breakingberta7220]

Is there a website to get a quote on your advisory services or project with someone you recommend for my new house?

[@HomePerformance]

Of course- BuildingPerformanceWorkshop.com

[@DennisMathias]

But my furnace company wanted me to buy an ionizer that fits right in the furnace. Bad? Also, what happens to a filter that gets dirty. Does it filter more? Can furnaces be retrofitted with larger higher filter products?

[@grantvogel759]

Yes as someone who has sold them in the past, I wouldn’t recommend them going forward. Ionizers have been shown in recent peer reviewed research to increase the levels of certain chemicals in the air. They also haven’t been proven to reduce particulate levels in the air and their evidence for viral removal is suspect at best. Yes filters that get dirty are actually more effective at capturing particles than when new. With that said you have to ensure that you are still moving a good amount of air through the filter for that to actually be true in practice. Google CADR (clean air delivery rate). I have a MERV 15 filter in my home and after a year (it looks filthy) the pressure increase was very small so I left it in and will continue testing. The smaller the filter, the sooner it will need to be changed. Furnaces can be retrofitted with assortment of different filter products. To be able to use a Merv 15 or 16 effectively, the filter needs to have a lot of surface area. Otherwise the pressure can be too high even before it gets dirt. The one I use is a Daikin filter and it is 28” x 24”. This is much larger than the usual 20 x 25” or 16” x 25”.

[@Beastphilosophy]

It's not the furnace that you need to retrofit: it's the return duct. The furnace is hopefully designed to handle volume of airflow that your house needs. If you can get a filter with enough surface area into the return, it can handle a higher MERV rating. If you're using a one inch filter, and you already have undersized ducts (which most houses do), good luck.

[@Balticblue93]

@@grantvogel759 28" x 24" x ?? What thickness? 1" is a vast difference to a 4"-6" thickness filter. Merv 15 in a 1" filter is worthless as nearly no system is setup to run that, but if it is a 5" filter that can flow proper CFM/FPM, that is a different story all together.

[@grantvogel759]

@@Balticblue93 It’s 5” or so. The cabinet is 7.5”. The static pressure readings are virtually the same as new after 18 months. Never seen anything like this before. Other MERV 16 products (MERV 15 is uncommon) are toast within 6 months.

[@Balticblue93]

@@grantvogel759 That is awesome to hear! I bet that baby can move and clean fantastic. I would love to find something like that for one of my doctor clients offices. 18 months with real static pressure increase is amazing in itself. Yeah, I haven’t seen a Merv 15 in my career as a tech or business owner but I am not shocked by that. You are right, Merv 16-up are gone in 30-90 days usually. Thank you for the response!!

[@dorhocyn3]

What about mr cool mini splits ? Can you retrofit something good onto them?

[@HomePerformance]

That would be a stretch. Separate powered filter unit would be a better way to go I think.

[@dorhocyn3]

@@HomePerformance ok, thank you...

[@dorhocyn3]

I like to use blue tape on my filter doors.

[@mikelittle1797]

I have a hard time with this video because you are not addressing the pressure drop issue. In the comments you replied that any system can handle a MERV 1000 filter if the area is big enough. I guess theoretically that is true, but your return would have to be bigger than the house? If you are advocating for use of MERV 16 in an existing system, then your wrong. The cost involved in retro-fitting for a 5" filter, along with the cost of the the filter and the increased energy consumption from the blower motor (200-300% at least) positive pressure, plus wear and tear on the equipment which will cause early failure, comfort issues due to low airflow. Most systems are designed for 0.5 IWC. A 3 ton system with a high quality 20x25MERV13 filter will have about a 0.3 pressure drop (I think most MERV13 are actually much higher some are 0.7). You are using at more than half of the recommended system allowance before the distribution system. Not only that, but when you start changing airflow, you affect humidity levels in the house and when you get out of the 45-50% sweet spot, you actually promote the growth of airborne pathogens. In the Atlanta house you are installing an IAQ system with HEPA filter. The house is at 0.5 ACH. Why would you need a MERV 16 for your recirculating HVAC system as well? I am not an expert, but I do know it is VERY difficult to design and install a system that operates at these pressure levels, let alone installing in an existing. Despite how... rude? I might sound, I do enjoy your submissions, and watch them all the time. I also subscribed to offset the negative comments, but the HVAC filter thing really bugs me. P.S. I watched the infiltration video where you pressure washed the house and looked for leaks. There is a product called Aero Barrier that might interest you

[@Sub-Zero-Homes]

If you want to see the dust shine a bright light in the room and move it around until you can. We have our own filters by the way of eyelashes and nose hair plus our ears so that shows how important it is to control such a thing. It's a shame filters don't work like a reverse osmosis water filter in that it removes the unwanted part but then dispses of it because a filter can't hold the vast amount of airborne particles for very long before you have to clean/replace it. Bit like nasal hair which blows the dust out again rather than collecting it. All the meters on the market seem to measure down to PM 2.5 but if it's 0.3-1 you're interested in then are they useful. We know the air is filled with dust etc so we don't really need a meter for that and we can guess what it comprises of too. I guess we need an extraction fan to the outside and a fan to bring in fresh air after being filtered and then an internal filter to clean the air but neither removes nor brings air in from the outside.

[@HomePerformance]

Good point on the RO, I like it

[@Level-333]

I just place a piece of wood in there. Blocks everything

[@HomePerformance]

Million dollar idea I’d say