Air purifier suggestions

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From what I’ve read it takes years and years of exposure to give you cancer from radon. So at least we have that going for us. Been in our current house for less than a year. Before that was an RV for a couple years. We’ve actually moved around a bit in the recent past.
 
A couple thoughts.

I started with some of the aesthetically pleasing air filter units that had good wife approval factor. When it was time to replace the filter elements in the fancy units the replacement filter element price had very low wallet approval factor.

HEPA is for sick people. On the MERV scale HEPA level filtration starts at MERV 14. The MERV scale was developed by ASHRAE, an HVAC industry group. If you have good MERV 13 filtration in your home and are still having issues, then look at HEPA. If you are an organ transplant recipient, sure, maybe start with HEPA level whole house filtration.

As above, the various symptoms associated with radon so far in this thread are concerning for lung cancer already having developed in the victim. However, there is another possible explanation. The RV had a ceiling vent fan, so good air turnovers. The house has no HVAC system (like mine), so relatively poor air turnovers. Besides the animals, how much carpeting do you have?

If you go reading up on carpeting, you will likely find they give off nasty chemicals for a year or two, and by then they are saturated with dust and pollen. If you want a dirt floor, put in wall to wall carpet. If you want clean air in your home, take out all the wall to wall, and buy the display version of various throw rugs that has been offgassing into the flooring showroom on a hanger system, but not picking up dirt. Wash the throw rugs on the driveway every spring with soap and a garden hose...

With all those animals - and probably some carpeting - the sustainable way to git 'er done is (as previously mentioned) is to duct tape a 20x20 furnace filter on the intake side of a 20 inch box fan and let it rip. I am also active on a woodworking forum, this is a probably safe step for most home owners in most situations. There are lots and lots of woodworkers who have been doing this in the garage to keep dust down in the house for decades and decades. You may purchase an infrared thermometer if you like to keep track of your fan motor's temperature while it is sucking through a filter. If you find more than 1 degree Fahrenheit temperature change between ambient air and motor temperature in this scenario I would very much like to hear about it.

I find the Lasko fan (home store team blue) is noticeably quieter than the black sexy similar item at home store team orange. For MERV 13 filtration you are looking for team orange "level ten" filters. On the 3M filtration scale, both the 1900 and 2200 Filtrete fall inside MERV 13 parameters. I buy the 3M 2200s by the dozen from that big online place, size 20x20x1.

With a geriatric long haired cat and a hard working woodstove I go through about 3 filters per year on one 20" Lasko.

My existing thread about indoor air quality is here: https://www.hearth.com/talk/threads/homemade-air-filters-good-indoor-air-quality-cheap.188986/
 
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We ordered one of the Blueair purifiers. Yeah I’m not looking forward to changing the filters in it. I’m sure they aren’t cheap.

The last place we lived in with an Hvac system, we changed out the filter monthly. And it needed I’d for sure. That was a 16x20 filter in an 1100 sq ft house. I remember reading about the Merv numbers back then.
We had some indoor air quality concerns and switched to a better filter. It made a difference.

I know the single purifier I bought won’t be enough. So I’m tempted to just get another box fan and use a filter with it like you say. The ole “ask for forgiveness instead of permission” type thing. It doesn’t work every time, but it’s worked in the past :)

I can always use another box fan, so it won’t be a waste regardless. I just so happen to be going past a Lowe’s later today.

I’m thinking I’ll pickup a radon monitor online. To watch the long term levels in the house. If it does have a high radon level, we’ve only been exposed to it for about 6 months. If you combine all the time when the house has been closed up.
 
I think I found the source of my air quality issues. There is some yellow mold growing in the crawl space.
Basically the crawl space is a not very well ventilated area. And when I use the woodstove or dryer I can feel air being drawn into the house from there in a few spots.

Guess I need to get rid of the mold, and then either ventilate the crawl space better, or totally insulate it. I do have plumbing down there, so probably adding insulation is the way to go. I need to put plastic over the ground as well.

I did get the Blueair air purifier. It’s pretty nice. And I’m also running a box fan with an air filter for now also. Until I can fix my problem under the house.

Also I’ve added two more temporary vents so I can get more airflow under there for now. And have a fan setup to pull air out of the crawl space to vent outside.
 
Thanks to the suggestions here I purchased a blueair unit last night. Best buy has a good sale going on now, about 130$ cheaper than normal price

purifier.jpg
 
nice unit looking at you pic the size is what holds be back from getting one.. Frigging thing is huge
 
nice unit looking at you pic the size is what holds be back from getting one.. Frigging thing is huge
It's really not as bad as it looks. The WAF is also very high, which helps.
 
Since you mentioned box fans and furnace filter, check out a corsi-rosenthal box. https://cleanaircrew.org/box-fan-filters/

I make them with two 10x20” filters cut in half and taped together and a 10” box fan, and then I use a blueair 211 pre-filter over top for aesthetics. I came up with this method because I have a blueair 411 (and like it and wanted more) but thought there had to be a cheaper and similarly effective solution. Ymmv on how “attractive” you think that is- but as about a 10” cube I put them in a corner and they seem innocuous enough to me.
 
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Hi All. Has anyone tried the Mila air purifiers? I gave them a try and they are not able to clean the air in my house. We burn the wood stove insert 24x7, about 5-6 cords a season. I recently read an article about how wood stoves pollute the air inside your house and how it is bad for your health. We have a 1 year old and I want to make sure the air is clean for him.

I purchased 2 Milas to see what my air quality is and to clean it. They showed me the air is bad with PM1 levels 100, PM2.5 averaging 150 and PM10 averaging 180. After a week of running the two Milas on full speed non stop, they have not made a dent.

So i am returning them and searching for an air purifier that actually works. They are also incredibly loud and you cannot hold a conversation with them running. One is in kitchen and one in living room (open concept).

I read this thread and also there's only a couple other threads on hearth about Purifier options. I can't find much on Google about which is best for combating wood stove air. It looks like the Allen 75i with Fresh filter works for someone above so I will give them a try and report back how they compared to the Milas to potentially help someone else in the future.
 
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I have not seen any studies that indoor air filtration will significantly impact home radon levels. Radon is a gas, HEPA filters are not designed to remove gases. Radon comes from three places, from the ground being pulled up from soil by the house sucking it in from the basement, from the source of household water (usually deep drilled wells) and to lesser amount from granite aggregate used in large concrete structures. The usual approach to ground based is subsurface slab ventilation where holes the basement edges, cracks and sumps are sealed, then new holes are drilled and vented to the outdoors with fans. Water based radon is usually air stripped with blower arrangement or in some cases multiple activated carbon filters.

Water based radon is arguably the most hazardous as it comes out of solution from the water best when its hot. When someone takes a shower, they are getting a higher dose right into their lungs versus household radon from the ground. Radon is heavy and tends to collect at the lowest elevation like a basement. It can bind to particulates so a filter can indirectly help by capturing the particulates.

Industrial operations on occasion use deep bed activated carbon filters to remove contaminants and radon would probably be removed but not very practical. I had a couple of them at my mill. One of them used to protect a 20 by 30 room had a 18" deep charcoal bed while the other one protected a house sized area with a 4' deep charcoal bed.
 
I have not seen any studies that indoor air filtration will significantly impact home radon levels. Radon is a gas, HEPA filters are not designed to remove gases. Radon comes from three places, from the ground being pulled up from soil by the house sucking it in from the basement, from the source of household water (usually deep drilled wells) and to lesser amount from granite aggregate used in large concrete structures. The usual approach to ground based is subsurface slab ventilation where holes the basement edges, cracks and sumps are sealed, then new holes are drilled and vented to the outdoors with fans. Water based radon is usually air stripped with blower arrangement or in some cases multiple activated carbon filters.

Water based radon is arguably the most hazardous as it comes out of solution from the water best when its hot. When someone takes a shower, they are getting a higher dose right into their lungs versus household radon from the ground. Radon is heavy and tends to collect at the lowest elevation like a basement. It can bind to particulates so a filter can indirectly help by capturing the particulates.

Industrial operations on occasion use deep bed activated carbon filters to remove contaminants and radon would probably be removed but not very practical. I had a couple of them at my mill. One of them used to protect a 20 by 30 room had a 18" deep charcoal bed while the other one protected a house sized area with a 4' deep charcoal bed.
Hello, Just to clarify my house does not have radon.
 
I recently read an article about how wood stoves pollute the air inside your house and how it is bad for your health. We have a 1 year old and I want to make sure the air is clean for him.
What article was that? I originally thought the same thing. Turns out our wood stove does absolutely nothing to pollute the air inside our house. The only time my purifier will ever speed up is if I make a mess cleaning out hot ashes and some fly in the room (fine dust).

Cooking on the other hand is terrible for our indoor air. I had no idea that it would pollute the air so much. I am very happy with our blueair unit, posted a picture of it above
 
What article was that? I originally thought the same thing. Turns out our wood stove does absolutely nothing to pollute the air inside our house. The only time my purifier will ever speed up is if I make a mess cleaning out hot ashes and some fly in the room (fine dust).

Cooking on the other hand is terrible for our indoor air. I had no idea that it would pollute the air so much. I am very happy with our blueair unit, posted a picture of it above
There's a handful of articles out there if you Google however here's a direct source of a recent study:


I found it to be accurate because the PM1, PM2.5 and PM10 levels are measured by the Milas and increase with the wood stove burning and remain high. If I move them to another room I can see the drastic decrease.
 
There's a handful of articles out there if you Google however here's a direct source of a recent study:


I found it to be accurate because the PM1, PM2.5 and PM10 levels are measured by the Milas and increase with the wood stove burning and remain high. If I move them to another room I can see the drastic decrease.
Interesting. It doesn't seem like the study differentiates between open fireplaces and stoves, they're combined. That ruins the validity of the study IMO. I did not read the whole thing, so I might've missed something. If the door is closed, there's just no way of anything getting in your house. The stove is working in a negative pressure zone, so if there is a leak air will get sucked in versus smoke coming out. Some people experience smoke rollout during reloads. For me, that's never been an issue. Any smoke gets sucked in the chimney.

I think there's simply too many variables eg. wood burning habits, dryness of wood, experience level of operator, draft strength, and other variables on indoor air quality to really make a point. My purifier is in the living room, far away from the kitchen. It never speeds up when the wood stove is burning. My wife can fry an egg in the kitchen, or use some hairspray in the bathroom (also far away) and the thing goes bananas.

My case may be an isolated one, but I know that my stove does not affect my indoor air quality like I thought it may have
 
On the other hand, the measurements by commguy35 can't be disregarded either - for his situation.

I have wondered whether an outside air kit would help, because all the air you're sucking into the stove will be replaced by air coming in thru gaps in the home. I know that my walls (which are unfortunately not very well sealed, '77 home), are rather dusty. So anything leaking in from there would be dirty air.

Not saying that is the cause of the air quality in commguy35's place (indeed, it could be simply the stove, especially if draft is not strong enough) - all I'm saying is that it's easy to miss parts of a complex system that could affect what is measured.

Regardless, it's good to be aware of potential issues, and mitigate them as much as possible. @Poindexter has done some measuring (and filtering) as well.
 
The main I have learned about wood burners in the UK is they are very small fireboxes, typically with a non-catalytic reburn chamber above the firebox and those little guys are finicky to reload because of the shelf between the fire box and upper secondary burn chamber. It is just super easy, at that small scale, for rolling smoke to come into the room instead of going around the lip and up the chimney.

I have had no response from the UK guy with the youtube channel I had put at the end of my air filter thread. In general I discount air quality editorial from the UK because I don't live in the UK and I really have to take my time on a hot reload, like stop and pee with the loading door open, to get the kind of indoor particulates they routinely publish in the media over there.

At my house, with a BK 30 sized box (it would be a monstrosity in the UK), I can get a little smoke rollout on reloads, but typically not measurable with an air sensor in the same room as the stove. My BK was installed in May 2014, so I am coming right up on 9 years experience with it.

I do agree with a previous poster a correctly installed stove should not be leaking smoke into the home with the loading door shut. If you do have smoke leaking into the house you need a chimney sweep or warranty work from your installer, not an air filter.

There was a multi-university team up here looking at indoor air quality lately. I think ALPACA working group. Pretty fascinating stuff, there is a youtube that runs about an hour....here:



good stuff. One of the data tables (quoting another study) found that length of ownership/ operation correlates strongly with reduced indoor particulates. That is to say, someone with a research grant found that the longer you own and operate the same stove, the less smoke rollout you get on reloads.

My previous thread about indoor air quality is in I think the DIY section here: https://www.hearth.com/talk/threads/homemade-air-filters-good-indoor-air-quality-cheap.188986/

Good luck and best wishes.
 
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Hi again. I see there are opposing studies on whether or not a wood stove pollutes air inside the house. I can confirm it does, unless 2 different Mila air purifiers and an Allen 75i air purifier are all incorrect.
I've attached some photos for refence showing the air quality in my house while the wood stove is burning 24x7, and then after letting the stove die on Tuesday (March 21). You will clearly see the mass improvement and stabilization in air quality without the wood stove burning.

For refence I have the Pacific Energy Sumit insert, about 1 year old now. Also worth mentioning I have been burning wood stoves for over 25 years, and am very careful when opening the door to reload and empty ash.

With wood stove burning:

9DD89919-5B13-4015-B8BE-52E51BE37012.png7258B450-0419-434D-93A2-A1FA65503508.png




Without wood stove burning:

FDE0A8A3-6647-4936-B811-3C905769D25F.png
 
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"whether or not a wood stove pollutes air inside the house. I can confirm it does".

No, you confirm it can because it does in your case.

That does not mean it does so in other cases.

Nevertheless, good for you for being on top of the air quality in your home, and taking measures to mitigate it.
 
Correct, my case is consistent with that of the study above, some facts from the study quoted below;

"In total, the study was based on 260 log burner uses.""Results from the study revealed that when the stoves were being used regularly - for approximately four hours - the level of harmful particulate matter pm1 and pm2.5 inside the homes were three times higher than the levels recorded when the stoves were not in use."

I have also found the $400 Mila air purifier vs the $800 Alen purifier (with filter intended for smoke) do not make a difference in the air quality while burning, neither is able to combat it while wood stove is in use. FYI I decided to return the Milas and stick with the Allen's. The Milas have a much better, more informative app however they use more power, and are ridiculously loud. Also the Allen has lifetime warranty whereas Mila is only 1 year.

I have burned wood stoves for decades in all of my 5 houses and never thought about or investigated the air quality until now, since we have an infant in the house.

I'm not sure where to go from here, perhaps the installer shop can double check their work but there is no visible smoke at any time in the house, the draft is strong, we do not even have a smell of smoke. Not sure how the air quality drops when stove is burning even though we cannot see or smell smoke, and I can see smoke stong pull up and out the chimney.
 
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I ended up with a Blue air 311 for the room the wood stove is in. I also have a box fan that I use with an air filter sometimes if the dust is really bad. Like when I clean out the woodstove, or when we clean the bird cages.

We have 4 green cheek conures and they do alright with this setup.

I run the air purifier on low 24/7 during burning season.
 
So I am still thinking about air purifiers mainly because I am in New York and the air quality is poor right now. I am kind of freaking out for my little sun conure.

Here are my questions, and please provide answers if you can.

1. I have heard Levoit is a good brand of air purifiers because I know they use a HEPA filter and don't have an ionizer. Does anyone use one.
2. How many air filters do I need? Her cage is in the family room, but she sleeps in a small upstairs bedroom.
3. How long do you keep the purifier running? How often do you need to replace filters?

I am trying to research this stuff and I still am not understanding this stuff
My my, youcertainly get around. UK, Canada, NY.
 
I have wondered whether an outside air kit would help, because all the air you're sucking into the stove will be replaced by air coming in thru gaps in the home. I know that my walls (which are unfortunately not very well sealed, '77 home), are rather dusty. So anything leaking in from there would be dirty air.
I have been thinking about this idea for coming up on a year, and I just can't let it go.

The home I had the big BK stove in was a 1980 build with 'vapor barrier' under the drywall and no hats on the jiffy boxes on the exterior walls, and the whole building was contractor grade execution.

When I installed the first wood stove, I think in 2012, and then upgraded to a BK in 2014, there was no outside air kit. I was, and continued, to suck make-up/ combustion air through all the leaks in the insulation envelope. I was in a pitched battle against incoming dust and mold spores the entire time. I actually got pretty good at replacing interior window trim, because every one of them leaked. I think I was able to salvage and reinstall something like 1:12 of the interior window trim.

But if I had started out with an OAK, would I maybe have been pumping heat out through my leaks instead of sucking pollutants inside the house from all the leaks? How nice it would have been to walk around the exterior every April and see where my big air leaks were evidenced by mold and dust on the exterior paint instead of loose inside the home.

I don't know if it would have worked, but I can tell you sucking combustion air through (uninsulated) 30 year old window margins introduces a bunch of junk to the interior spaces.
 
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