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Ceiling Air Purifier

jefftk.com

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Re: Ceiling Air Purifier

#111

Post by formerkrogemp »

titanomachy wrote: post #53
formerkrogemp wrote: post #45

Earlier quoted context omitted.

This is very similar to what hobbyist mushroom growers use in our setups to inoculate substrate in a 'sterile' environment. Other methods include using sterile, hot oven air, buying very expensive equipment, and making a still air box at home with a plastic tote box. Good times.

In college we used to work under a bunsen flame, is that not enough space?

I think a lot of those options are born out of creativity. Inoculation typically happens from jar to jar or from a jar to a block of substrate for instance. A Bunsen burner would probably work well for many applications in mycology. I only ever used one in cell bio, and only a mini Bunsen in my mushroom hobby.

Re: Ceiling Air Purifier

#112

Post by mxfh »

jefftk wrote: post #64
maxk42 wrote: post #57

Is nobody going to mention what a pain in the ass it would be to change all those filters regularly? I love in a somewhat dry and dusty area and need to change my filters (near the ground) every two to three months. I'd hate to have to climb up a ladder to change eight to nine filters that often.

Unless your ceiling is very high you probably wouldn't need a ladder to change the filters on a productized version of this. Reach up, twist something to unlock, old filter slides out, slide in new filter, twist to lock. Repeat for each filter going around. Ten minutes every six months?

Not to forget, you'll have a looming black octagon after 6 weeks or so already depending on your environment. At least a reminder, that the filters are doing something useful.

Re: Ceiling Air Purifier

#113

Post by Pxtl »

blagie wrote: post #52

I think people are missing the point. YES this is bad engineering for a finished product: - The fan is not designed for high static pressure. It won't do well pulling air through filters. - It's ugly. It will get uglier as filters get dirty. - It's expensive to replace filters. - Etc. But it's not a finished, industrial project. It's a prototype. Those sorts of issues are universal for prototypes. They're easy to add…

If we're looking for a finished product, we're leaving a tool on the shelf -- filters aren't the only option. Pipe the air through a duct flooded with deadly UV-C and sterilize the air instead of just filtering it.

Re: Ceiling Air Purifier

#114

Post by ev1 »

mrfusion wrote: post #99
atmartins wrote: post #95

Earlier quoted context omitted.

Yes. And it's on your home IP address. I see things based on what others in my household have done with Tok Tok

So how would the tracking work exactly? Does this website have trackers that other companies can access? Is there any way to block that?

yes, this website loads the full adtech parade.

Re: Ceiling Air Purifier

#116

Post by euroclydon »

sfteus wrote: post #97
sha256sum wrote: post #6

Great idea. What's worked for me is simply taking a 20"x20"x1" filter and sliding it into the back cover of a standard $25 Lasko box fan. Cheap, easy option for air filtration in the home.

I did this for a cheap dust filter when demoing a ~7 cu ft concrete shower pan in my house. Pretty incredible how much material it pulled out of the air; I ended up running through 3-4 filters total throughout the whole process.

I prefer to mount a high-power fan in the bathroom window for demolition.

Re: Ceiling Air Purifier

#117

Post by kube-system »

post_break wrote: post #42
bombcar wrote: post #5

If you have a whole-home furnace you can often make it run the fan even if cool/heat is off - and install a high power filter and change it regularly and it’ll filter the air reasonably well. The ecobee has a “minimum fan time per hour” setting - it can also help to balance the air temperature.

My dad worked in AC his whole life. Do not put a constrictive filter on your ac. He even recommends the cheap ugly ones as they are the least restrictive. The AC is not meant to filter air. The only reason it has filters is to keep large particles out of the evaporator coils.

You don't want to restict the total amount of flow, but with more media area you can have a tighter filter media with the same (or even better!) total flow.

A thicker filter and/or one with more pleats can filter better and be less restrictive at the same time.

https://www.youtube.com/watch?v=RkjRKIRva58&t=454s

Re: Ceiling Air Purifier

#118

Post by bityard »

foobarian wrote: post #38
malfist wrote: post #35

Earlier quoted context omitted.

I've always heard this, but I don't know that that's true. The thing that dies first on an HVAC system isn't the motor, it lasts a long damn time, it's the capacitor, or contactor or some other fault not really related to the motor work load. Plus, your "motor" isn't an engine, it's not variable speed, it only has one "hardness" that it works at. It might push less air with the thicker filter, but it's not going to r…

>Plus, your "motor" isn't an engine, it's not variable speed, it only has one "hardness" that it works at. This is incorrect - electric motors draw more current when under load. I would suggest researching this or playing with some toy electric motors run from a battery through a current meter.

> This is incorrect - electric motors draw more current when under load.

Which is a true statement but incomplete and therefore misleading. A fan motor is under the highest load when it is doing the most work. That is, moving the MOST air. If you restrict airflow (e.g. with a dirty filter), the motor is under less load and draws LESS current. A lot of people get this wrong because it's counter-intuitive on the surface of it.

You can test this very easily with a box fan and a kill-a-watt. Turn the fan on High in the center of the room and read the power. Now move it against the wall. You will hear the fan get louder because it is spinning faster, because it's doing LESS work. The meter will also show less power being drawn.

It is true that a dirty filter restricts airflow through the whole HVAC system. This extends the system's "on" cycle, which reduces the whole system's efficiency. But the popular claim that a dirty filter will burn out the motor is bunk.

Re: Ceiling Air Purifier

#119

Post by bredren »

alexpw wrote: post #71
kolencherry wrote: post #55

Earlier quoted context omitted.

Yes! This is the basis for the Corsi-Rosenthal Box [1]. Five 20"x20"x1" filters and a box fan, with duct tape to seal the edges. Not the prettiest, but it's effective. [1] https://en.wikipedia.org/wiki/Corsi%E2%80%93Rosenthal_Box

> An updated design, also known as a Comparetto Cube, [1] uses four filters and a cardboard base that can sit directly on the floor. I never understood the purpose of the bottom filter in the Corsi-Rosenthal Box, so it felt like a waste of a filter, but I'm a big fan of the Comparetto Cube (no put intended). And 4 packs of filters are readily available -- 20x20x2 is suggested for the Comparetto Cube. [edit] Also, tha…

I have been focused on HVAC / air purification recently.

Its amazing to me that these designs are less than two years old when the tech has been available for decades.

One of the biggest problems with the C-R and comparetto is that they are large and hideous to look at.

I have been working on a design that makes the C-R or comparetto or a smaller version than the 20" something that can be attractive enough to hang in the corner of a room as both an air purifier and room lighting.

Re: Ceiling Air Purifier

#120

Post by bredren »

hinkley wrote: post #91
sha256sum wrote: post #6

Great idea. What's worked for me is simply taking a 20"x20"x1" filter and sliding it into the back cover of a standard $25 Lasko box fan. Cheap, easy option for air filtration in the home.

Tends to burn out the motor though. Vornado used to sell an air filter that took two 10x20” house filters. Before I discovered that model I was trying to build my own using computer case fans (my intent was to hide the loud box under furniture). Home Depot used to carry those in the 1500 classification which was great, but those are getting harder to come by too, and even the regional chain that had them doesn’t as m…

> Tends to burn out the motor though.

Do you have data on this? Adding a fan shroud to the Corsi-R supposedly does not increase energy usage or motor temperature:

https://www.texairfilters.com/how-to-improve-the-efficiency-...

I'm looking for data on the power usage and motor temperature difference from a 20" Hurricane in normal operation, with a 20" merv 14 on the back, a C-R and a Comparetto.

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