Does air conditioning reduce PM2.5 ?

[OneMoreFarang]

4 minutes ago, KhunLA said:

Were they in the same room before ?  Do you smoke ?

 

Is one closer to cooking area or bathroom, (shower/moist air) ?

 

I smoked a doobie with AQI meter next to me, and it shot up to 600  

 

Smoking weed isn't harmful to your health ... really, trust me 

 

I noticed the effect of cigarette smoke.

 

Before I never used them together anywhere near each other. After testing them now together I guess I will move on of them near to my computer desk.

 

 

[SiSePuede419]

No.

 

Air filters and the much feared "Fauci Mouth Diaper" can help however . 😘

 

While a standard AC alone may not significantly reduce PM2.5, models with advanced filtration or air purification capabilities can help. To ensure effective PM2.5 reduction, consider an AC system with HEPA or similar filters.
 

[ricklev]

On 1/25/2025 at 6:40 PM, StephenD said:

If you have an old aircon unit that doesn't filter PM2.5, then you can buy a roll of 3M Filtrete paper and stick it to the mesh filter inside your unit. This will filter out most of the PM2.5.

This works!  I have a PM2.5 meter and I know.  It doesn't reduce it to 2 ppm as my air purifier does but it does get down to 10 ppm from 80 ppm in an hour or so.  You have to follow the directions it comes with.  However, I do have an old fashioned giant floor type split unit mounted on my ceiling so a lot of air is passing through. 

[brfsa2]

On 1/26/2025 at 7:42 AM, msbkk said:

Just to show the change of 3M filter colors within around 3 weeks in the center of Bangkok.

 

Yep, I've been doing the same for the past 8 years.

many years ago was just the same as today, but I never seen as bad as 2024-2025 has been, back then that nobody really realized back then how bad it was already.

 

I started adding an extra Pm2.5 filter to all my air-cons was to save money from washing them every 4 months, with the filters on, I hire the team to wash once a year, 6 air-cons used to cost at least 3000 baht to wash. It's more now.

 

I dont recommend 3M filters, first it's way over priced for such a small amount, and it's full of holes! It doesn't catch everything as good as the other PM2.5 sheets that are more uniform and leaves no holes.

 

 

 

 

[digger70]

The experimental results showed that household air conditioners have a purification effect on particulate matter. Under the refrigeration mode of maximum air volume, the concentration reduction efficiency of PM2. 5 and PM10 reaches 60.99% and 57.47% respectively.

[motdaeng]

i recommend everyone buy a simple pm2.5 meter. good air quality should be below 10 µg/m³ for pm2.5! 

 

i did some tests a few years ago, got rid of the air conditioner filters, and now use only air purifiers, which keep the pm2.5 levels inside my house consistently low. convincing yourself, putting the air con a 3m filter alone is enough to tackle high air pollution might be a solution, but it’s not an effective one.

 

 

[SunsetT]

On 1/25/2025 at 11:11 PM, NativeBob said:

Clean AC working in closed room/flat will reduce amount of any particles. Basic physics.
But air purifier is the better choice as it is intended to "purify" air. And less electricity 

Can anyone recommend a good compact air purifier please?

[OneMoreFarang]

11 minutes ago, SunsetT said:

Can anyone recommend a good compact air purifier please?

 

Xiaomi Smart Air Purifier 4 Lite - Xiaomi ประเทศไทย

https://www.mi.com/th/product/xiaomi-smart-air-purifier-4-lite/

 

I have the previous model 3. It does a good job.

[motdaeng]

air purifiers usually indicate the recommended room size in square meters. from my experience, the air circulation capacity (m³) should be at least three times the room's volume. factors like the room's air tightness and the severity of maximum air pollution can influence this value.

when buying an air purifier, also consider the availability of replacement filters. even simple and inexpensive air purifiers can do their job well, but they are often quite noisy. do not forget to buy also a pm2.5 meter ....

 

 

 

[Nemises]

Simply place a piece of PM 2.5 filter cloth behind a portable fan. Watch it turn black in a few hours. Thank me later!

[buick]

39 minutes ago, OneMoreFarang said:

 

Xiaomi Smart Air Purifier 4 Lite - Xiaomi ประเทศไทย

https://www.mi.com/th/product/xiaomi-smart-air-purifier-4-lite/

 

I have the previous model 3. It does a good job.

 

i've been using a 2s model from Xiaomi for a couple years (only use during the bad air months).  it works great.   i've recommended their models to others and they've been happy with theirs.

[msbkk]

2 hours ago, brfsa2 said:

 

Yep, I've been doing the same for the past 8 years.

many years ago was just the same as today, but I never seen as bad as 2024-2025 has been, back then that nobody really realized back then how bad it was already.

 

I started adding an extra Pm2.5 filter to all my air-cons was to save money from washing them every 4 months, with the filters on, I hire the team to wash once a year, 6 air-cons used to cost at least 3000 baht to wash. It's more now.

 

I dont recommend 3M filters, first it's way over priced for such a small amount, and it's full of holes! It doesn't catch everything as good as the other PM2.5 sheets that are more uniform and leaves no holes.

 

 

 

 

Regarding the price I always buy the 270cm rolls which is cheaper, not the precut version. I cut my own sheets. But ok, probably

worth to check out other brands as well.

[Will B Good]

1 hour ago, Nemises said:

Simply place a piece of PM 2.5 filter cloth behind a portable fan. Watch it turn black in a few hours. Thank me later!

 

Just being reading up on that.....apparently sticking a HEPA filter anywhere near the intake of any kind of room fan is quite effective!!!!

[Nemises]

19 minutes ago, Will B Good said:

 

Just being reading up on that.....apparently sticking a HEPA filter anywhere near the intake of any kind of room fan is quite effective!!!!

Thanks, and as evidenced in my photos!

[Will B Good]

1 minute ago, Nemises said:

Thanks, and as evidenced in my photos!

 

Just ordered some sheets.....will try them on a pedestal fan and/or the air-con intake.....or a % of the intake??

[Nemises]

Just now, Will B Good said:

 

Just ordered some sheets.....will try them on a pedestal fan and/or the air-con intake.....or a % of the intake??

I use a % on a ped fan. The % depends on how hot it is as the cloth obviously reduces the air flowing out. 
 

I cover ALL of the air-con intake when the AC is needed when air temp/humidity gets too high for the ped fan. 
 

As mentioned above by another, the 3M HEPA cloth is over-priced. Lazada has much cheaper cloth options which work just as good. 

[Will B Good]

5 minutes ago, Nemises said:

I use a % on a ped fan. The % depends on how hot it is as the cloth obviously reduces the air flowing out. 
 

I cover ALL of the air-con intake when the AC is needed when air temp/humidity gets too high for the ped fan. 
 

As mentioned above by another, the 3M HEPA cloth is over-priced. Lazada has much cheaper cloth options which work just as good. 

 

Did you notice any change in the functioning of the air con? Motor straining etc?

[OneMoreFarang]

3 hours ago, buick said:

 

i've been using a 2s model from Xiaomi for a couple years (only use during the bad air months).  it works great.   i've recommended their models to others and they've been happy with theirs.

 

I guess at the end of the day it's a filter with a fan. If the filter is good, then it should work.

[Nemises]

44 minutes ago, Will B Good said:

 

Did you notice any change in the functioning of the air con? Motor straining etc?

Good question, nothing noticeable. Probably worth researching though. 

[Callmeishmael]

On 1/25/2025 at 12:30 PM, fvw53 said:

I live in an apartment opposite Bangkok Golf Club in Pathum Thani where according to AQAir.com the PM2.5 was 180 at 12 noon.

I keep my air conditioner operating the whole day at a setting of 28 C

Recently a bought an Air Quality Detector and it indicates in my apartment a PM.5 value of 29 (also at 12 noon)

Does air conditioning reduce PM2.5  and keep the dust in the filter?

 

I hate to be pedantic, (actually that's a lie, I love being pedantic!) but you are comparing two different things.  The map is showing the local AQI or Air Quality Index, while your Air Cleaner is showing PM2.5 in ppm. 

 

AQI is a composite figure that includes particulate matter (PM1, PM10, PM2.5) as well as CO2 levels, NOx levels, SO2, etc...  If the AQI is 180, the PM2.5 will typically be anywhere from 20 to 80. 

 

If you click on the 180 figure, you should be able to see more detailed information from that reporting station, including the actual PM2.5..

[KhunLA]

@OneMoreFarang Got me thinking so did a test, let the outside air in for more than a few hours.  Impressive, and spot on with local reading.  We're just a couple kms from that tambon, I think.  Where ever they source the info from, pretty damn accurate.

 

 

 

The state they source it from radar ???

https://www.accuweather.com/en/th/ban-thung-khlet/436192/air-quality-index/436192

 

 

15 minutes later, and we're back to heathy, just the purifiers on.

 

[motdaeng]

different readings on your own pm2.5 meter compared to the various measuring stations available online depend on several factors. for example, whether waste is being burned nearby, farmers are burning fields, or even the wind direction, etc.

 

my simple tip: invest in your own pm2.5 meter and keep it running 24/7. what matters most is the reading inside your house, not the one from a measuring station 30 km away ... 

 

edit: don't get confused between the AQI numbers and the pm2.5 µg/m³ values ... 

 

[KannikaP]

On 1/25/2025 at 1:13 PM, Raindancer said:

Surely running the fan increases power consumption.  But does indeed stop the compressor running.

 

https://breathebetterair.org/all-post/fan-mode-on-ac/

Fan only = 30 watts, aircon on = 500/1000 watts.

[KannikaP]

4 minutes ago, motdaeng said:

different readings on your own pm2.5 meter compared to the various measuring stations available online depend on several factors. for example, whether waste is being burned nearby, farmers are burning fields, or even the wind direction, etc.

 

my simple tip: invest in your own pm2.5 meter and keep it running 24/7. what matters most is the reading inside your house, not the one from a measuring station 30 km away ... 

 

And if your personal indoor meter says 100, then what?

[motdaeng]

3 minutes ago, KannikaP said:

And if your personal indoor meter says 100, then what?

 

then you're busted ... 

[KannikaP]

1 hour ago, motdaeng said:

 

then you're busted ... 

If I leave the kitchen door open whilat cooking, it can go up to 300 or more. Quickly goes back down though.

 

[BE88]

 

Only some newer air conditioners do this like my newer TCL while two others don't because they are older

[steven100]

Your AC has a built in filter system that will eliminate PM 2.5 ....

It will automatically filter the air while running.

 

mine is the same ....

[SanSaiExPat]

On 1/25/2025 at 12:30 AM, fvw53 said:

I live in an apartment opposite Bangkok Golf Club in Pathum Thani where according to AQAir.com the PM2.5 was 180 at 12 noon.

I keep my air conditioner operating the whole day at a setting of 28 C

Recently a bought an Air Quality Detector and it indicates in my apartment a PM.5 value of 29 (also at 12 noon)

Does air conditioning reduce PM2.5  and keep the dust in the filter?

 

How often do you all have a guy come out and clean your A/C unit and what to you pay?  500 baht?

[outsidetrader]

On 1/25/2025 at 12:30 PM, fvw53 said:

I live in an apartment opposite Bangkok Golf Club in Pathum Thani where according to AQAir.com the PM2.5 was 180 at 12 noon.

I keep my air conditioner operating the whole day at a setting of 28 C

Recently a bought an Air Quality Detector and it indicates in my apartment a PM.5 value of 29 (also at 12 noon)

Does air conditioning reduce PM2.5  and keep the dust in the filter?

 

Yes indeed it does :)