4 ms·

There doesn't seem to be good control tests to say what difference the filters really make - seems one was added in in the comments, but it's missing important

There doesn't seem to be good control tests to say what difference the filters really make - seems one was added in in the comments, but it's missing important details (is the control with everything off? What happens if the fan is running on medium or high, etc.? And, of course, it's not really practical in that most people really don't want to be sticking stuff on their ceiling, but it could be an interesting experiment with more details provided.

sdflhasjd 4y ago
It's not clear how this performs over having no fans and filters at all.
- flybrand 4y ago
  Agreed - and another wish list item would be a basic room air purifier “RAP” off the shelf, sitting in the corner. OP will also want to track performance over time. How long does it take the filters to load.
  - jefftk 4y ago
    The first chart in the post compares performance against a RAP (Coway AP-1512HH Mighty, the Wirecutter's top pick): https://www.jefftk.com/mighty-vs-ceiling-decay-big.png https://www.jefftk.com/mighty-vs-ceiling-decay-big.png
  - jefftk 4y ago
    > How long does it take the filters to load This is basically the same question as "how long does a filter cube last". See https://www.texairfilters.com/testing-the-efficiency-of-merv-13-corsi-rosenthal-boxes-in-use/ https://www.texairfilters.com/testing-the-efficiency-of-merv... where they found performance was still good at 6m, though decreasing at 10m.
SamBam 4y ago
I was thinking the same thing. He has graphs for how quickly the pm2.5 levels reduce compared with a commercial machine, but not compared with running the fan alone, without filters. I believe that it is quite possible the majority of the air is not going through the filters. It seems that much of the air might spill out down the insides of the filters, rather than being forced through. In that case, the graph could be equally explained by the fan causing outside air to be sucked in.

sdflhasjd 4y ago

It's not clear how this performs over having no fans and filters at all.

flybrand 4y ago
Agreed - and another wish list item would be a basic room air purifier “RAP” off the shelf, sitting in the corner. OP will also want to track performance over time. How long does it take the filters to load.
- jefftk 4y ago
  The first chart in the post compares performance against a RAP (Coway AP-1512HH Mighty, the Wirecutter's top pick): https://www.jefftk.com/mighty-vs-ceiling-decay-big.png https://www.jefftk.com/mighty-vs-ceiling-decay-big.png
- jefftk 4y ago
  > How long does it take the filters to load This is basically the same question as "how long does a filter cube last". See https://www.texairfilters.com/testing-the-efficiency-of-merv-13-corsi-rosenthal-boxes-in-use/ https://www.texairfilters.com/testing-the-efficiency-of-merv... where they found performance was still good at 6m, though decreasing at 10m.

SamBam 4y ago

I was thinking the same thing. He has graphs for how quickly the pm2.5 levels reduce compared with a commercial machine, but not compared with running the fan alone, without filters. I believe that it is quite possible the majority of the air is not going through the filters. It seems that much of the air might spill out down the insides of the filters, rather than being forced through. In that case, the graph could be equally explained by the fan causing outside air to be sucked in.