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Smoke has caused temperature forecasts to go crazy

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Re: Smoke has caused temperature forecasts to go crazy

#281

Post by mehrzad »

BoiledCabbage wrote: post #166
jschwartzi wrote: post #146

Earlier quoted context omitted.

If you have central heat you can sometimes configure the thermostat to run the blower separately from the heating element. This creates a nice positive pressure environment. If you have a MERV 10 or better filter installed on the furnace then it's actually pulling in filtered air, as any high enough MERV filter will filter PM2.5 with a decent efficiency. I think they start filtering PM2.5 at about MERV 10, and by MER…

MERV Table with filtration amounts - https://www.lakeair.com/merv-rating-explanation/ I'm guessing the table lists filtration for a single pass through the filter. But through constant circulation a greater reduction in air particulate can be achieved. Anyone know this for certain?

I would like to know this as well but the way the products are advertised, it would seem that this isn't a single pass-through measurement (see The Wirecutter)

Re: Smoke has caused temperature forecasts to go crazy

#282

Post by koolba »

ALittleLight wrote: post #153
Qub3d wrote: post #112

Earlier quoted context omitted.

The University of Michigan made an instructional video showing how you can easily make an air purifier out of a box fan and a HEPA-rated furnace filter for $25: https://www.youtube.com/watch?v=kH5APw_SLUU It won't be as good as a purpose-built machine, but it will be far better than nothing at all. TheWirecutter found it reduced particulate matter in a room by 87%, if you do it right. They also make clear important c…

I have two of these running right now. According to my air quality meter, PM 2.5 has fallen from about ~250 indoors to ~40. (My meter shows ~600 outside, which is about 3x what the government website shows for my area)

What do you use to measure air quality?

Re: Smoke has caused temperature forecasts to go crazy

#283

Post by ComputerGuru »

jschwartzi wrote: post #146
hguant wrote: post #91

Earlier quoted context omitted.

>I'm not looking forward to any smoke now my dad has COPD, IPF, is on oxygen, and he's elderly. If we get any amount of smoke here it will be the end of him. It's hard enough trying to keep him from contracting SARS-Cov-2 and developing covid-19 Seriously, get a HEPA rated air filter. Speaking as someone who has some serious lung issues, it's literally life changing/saving. Honeywell sells a number of models, cost is…

If you have central heat you can sometimes configure the thermostat to run the blower separately from the heating element. This creates a nice positive pressure environment. If you have a MERV 10 or better filter installed on the furnace then it's actually pulling in filtered air, as any high enough MERV filter will filter PM2.5 with a decent efficiency. I think they start filtering PM2.5 at about MERV 10, and by MER…

Where is the positive pressure element coming from? Most residential HVAC systems are closed and do not have an intake (note: not commercial, which are typically in the USA required to include an air exchanger or other fresh air ventilation component).

Your typical 1980s construction home likely does not have mechanical ventilation, the only inlet would be for fresh air to facilitate the combustion in the furnace (alongside an exhaust for carbon dioxide and carbon monoxide).

Re: Smoke has caused temperature forecasts to go crazy

#284

Post by axaxs »

ComputerGuru wrote: post #283
jschwartzi wrote: post #146

Earlier quoted context omitted.

If you have central heat you can sometimes configure the thermostat to run the blower separately from the heating element. This creates a nice positive pressure environment. If you have a MERV 10 or better filter installed on the furnace then it's actually pulling in filtered air, as any high enough MERV filter will filter PM2.5 with a decent efficiency. I think they start filtering PM2.5 at about MERV 10, and by MER…

Where is the positive pressure element coming from? Most residential HVAC systems are closed and do not have an intake (note: not commercial, which are typically in the USA required to include an air exchanger or other fresh air ventilation component). Your typical 1980s construction home likely does not have mechanical ventilation, the only inlet would be for fresh air to facilitate the combustion in the furnace (al…

AFAIK, most new construction houses for the past decade or so have some amount of air intake, because houses are built too 'tight' now, but this might be somewhat location dependent.

Re: Smoke has caused temperature forecasts to go crazy

#285

Post by proee »

y-c-o-m-b wrote: post #179
blendo wrote: post #164

Earlier quoted context omitted.

Even easier: just place the 20”x20” filter BEHIND the box fan. The vacuum will keep it in place nicely. Be sure to note the airflow direction arrows on the filter.

I put it behind the fan as well, but now I'm curious if there a difference in air quality between the two methods?

Putting the filter behind the fan ensures you have clean air contacting the fan blades. This prevents contaminants from accumulating on the fan blades over time and reduces cleaning.

Re: Smoke has caused temperature forecasts to go crazy

#286

Post by nthj »

kiddico wrote: post #280
bfuclusion wrote: post #271

Earlier quoted context omitted.

I use these guys to have them shipped. Comes in a few days, but this is going to last a while https://www.secondnature.com/

I realize that air filters are the perfect candidate for a subscription service... but it's just insane the that every product in existence has a business prepared to ship some of it to you monthly.

As long as the markets value ARR at a 3-10x multiple, subscription businesses will continue to appear :)

Re: Smoke has caused temperature forecasts to go crazy

#287

Post by DoofusOfDeath »

bcbrown wrote: post #275
DoofusOfDeath wrote: post #181

Earlier quoted context omitted.

Why is that? Sap content? I just started reading Hoadley's "Understanding Wood" [0], which has gotten me interested in wood's characteristics. [0] https://www.amazon.com/gp/product/1561583588/ref=ppx_yo_dt_b...

Some species are specifically adapted to either be able to survive frequent brush fires, and some even require them for seedlings. Douglas-fir trees have very thick, insulative bark that prevents the live tissue from dying as readily when there's fire. Sequoia trees have cones that are glued shut by resins that only melt after a hot-enough fire, so they can then land and germinate in burnt-over ground. https://en.wik…

Thanks for explaining! Trees are amazing.

Re: Smoke has caused temperature forecasts to go crazy

#288

Post by joe_the_user »

reissbaker wrote: post #198
ALittleLight wrote: post #157

Earlier quoted context omitted.

This propublica story has a lot of detail on the fires. They estimate that there are ~20 million acres overdue for burn and the fires this year are burning about a million acres. If I understood it correctly a million acres burning a year is about what's required for stasis, but the 20 million acre backlog will need to be burned too. https://www.propublica.org/article/they-know-how-to-prevent-...

At this point over 3 million acres [1] have burned in CA alone. So, seems like some of the 20 million acre backlog is getting burned through this year. 1: https://www.fire.ca.gov/daily-wildfire-report/

OK, so in three equivalent years, 50% of what needs to go will be gone - and that will give "herd immunity" to the unburned parts - 'till those get large again, say in 5 more years.

Re: Smoke has caused temperature forecasts to go crazy

#289

Post by kirillzubovsky »

bfuclusion wrote: post #271
kirillzubovsky wrote: post #239

Yup. It's been a fun weekend. Everyone in the family is feeling the cabin fever, but outside (Bellevue, WA) smells like inside of a fireplace. We put a few boxed fans with HEPA filters around the house and they are now black. In hindsight, should've bought more filters, but all the stores and Amazon are sold out for the near future. Speaking about the future, this puts planning in perspective. With the climate changi…

I use these guys to have them shipped. Comes in a few days, but this is going to last a while https://www.secondnature.com/

Smart idea. Whatever filters I picked up come with a little bluetooth chip on them and require an account with the manufacturer to get air quality information. I didn't bother for privacy reasons, but judging by 40k reviews on Apple Store, there are plenty of people who are subscribed to their air filter delivery. It makes a lot of sense.

Re: Smoke has caused temperature forecasts to go crazy

#290

Post by kirillzubovsky »

chris1993 wrote: post #255
kirillzubovsky wrote: post #239

Yup. It's been a fun weekend. Everyone in the family is feeling the cabin fever, but outside (Bellevue, WA) smells like inside of a fireplace. We put a few boxed fans with HEPA filters around the house and they are now black. In hindsight, should've bought more filters, but all the stores and Amazon are sold out for the near future. Speaking about the future, this puts planning in perspective. With the climate changi…

Be sure to have a bypass on your rain system to flush the smoke precipitates off your roof before they get into the tank. My parents water used to taste of tar over winter when they were lighting their fire.

Good to note! One thing I definitely want to do when I have the means is built a cabin/house with the latest and greatest efficiencies. Not in a hippy-earth-loving way, but more in a curious engineer way.

Did you know there are these things called Earthships in New Mexico? It's a bit too hippy for me, but on the right track.

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