Air purifier? - Part 2

klarklar

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Sorry, this thread is very long. I can't read all the posts.

Lately, the air is bad because of our neighbouring country. I think my health is suffering as a result. Can't sleep well at night. Woken up by bad air.

Can experienced folks here recommend good air purifiers? Are they effective in the first place?

I don't mind paying high price for quality air purifiers as long as they really work.
 

WussRedXLi

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Sorry, this thread is very long. I can't read all the posts.

Lately, the air is bad because of our neighbouring country. I think my health is suffering as a result. Can't sleep well at night. Woken up by bad air.

Can experienced folks here recommend good air purifiers? Are they effective in the first place?

I don't mind paying high price for quality air purifiers as long as they really work.

Last 3 pages more than sufficient be it haze or recent Sungai Kim Kim VOC "scare". All info posted liao. Won't take you > 30 mins to digest.
 

WussRedXLi

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To bring the 352 X83C Plus in, go to the TB thread and contact bro MRC. He can handle for you. Basically sensitive sea shipping. I reckon 0.2 cbm is sufficient, or SGD 60.
Get 1 set of extra filter to standby, is enough to last you pretty long.
 

WussRedXLi

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Seems like Xiaomi 2S is a good purifier to buy. Can't go too wrong.

Very small footprint, easy to buy and cheap filters, performance is decent. You just scale it up with multiple units. Only issue is that for 300m3/hr of airflow from the X83C Plus, the 3pcs of Xiaomi 2S in med-low speed is still going to be slightly noisier. I think 3pcs of Xiaomi 2S foot print = 1 pc X83C Plus or close to it. 3 pcs Xiaomi filters might still cost half that of 1 set of X83C Plus, and filter capacity ought to be close with the X83C Plus a bit higher.

Basically the X83C Plus is a 600 m3/hr formaldehyde machine, if basing yr needs on Sungai Kim Kim/Pasir Gudang "risk".

Pro with the 2S is that multiple units give you the flexibility of moving the units around the house.

Of coz you still can do that with the X83C Plus multiple units if there is a need coz you are living in a huge condo or what. You can't really buy 1 dozen units of cute Xiaomi 2S, very difficult to manage. :D
 

klarklar

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Very small footprint, easy to buy and cheap filters, performance is decent. You just scale it up with multiple units. Only issue is that for 300m3/hr of airflow from the X83C Plus, the 3pcs of Xiaomi 2S in med-low speed is still going to be slightly noisier. I think 3pcs of Xiaomi 2S foot print = 1 pc X83C Plus or close to it. 3 pcs Xiaomi filters might still cost half that of 1 set of X83C Plus, and filter capacity ought to be close with the X83C Plus a bit higher.

Basically the X83C Plus is a 600 m3/hr formaldehyde machine, if basing yr needs on Sungai Kim Kim/Pasir Gudang "risk".

Thanks for recommendation. X83C Plus is a bit hard to get approval from wife because of the price tag. It seems for value-for-money, Xiaomi 2S doesn't look too bad a choice.

I live in HDB. Not high-SES big property, so perhaps cheaper air purifiers that cover small areas good enough for me.

Can ask you which one you bought or consider buying? Can ask whether you live in >=4-room HDB or big house?
 

WussRedXLi

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That day my purifiers also auto became offline. :s22:

Tried the usual setup few times cannot detect. Reset purifier—> Add purifier in app —> Toggle to phone settings to change to purifier wifi —> Toggle back to app to continue setup. :(

So I go try the other way. Reset purifier —> Goto Phone settings first and select purifier wifi —> Launch the app to add purifier ... somehow it works. :s22: :s13:

Xiaomi expert, you got the 2S's CADR for formaldehyde with the formaldehyde filter? Can't really find it via google.
 

WussRedXLi

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Thanks for recommendation. X83C Plus is a bit hard to get approval from wife because of the price tag. It seems for value-for-money, Xiaomi 2S doesn't look too bad a choice.

I live in HDB. Not high-SES big property, so perhaps cheaper air purifiers that cover small areas good enough for me.

Can ask you which one you bought or consider buying? Can ask whether you live in >=4-room HDB or big house?

I live some 30km away from Malaysia PG so i think the VOC risk @ toxic levels is not high. So i am just operating pretty normal stuff for indon haze risk, Samsung, Sharp, and one odd-ball called MFresh coz it's damn cheap @ rmb 899 then in 2015 and weighs only 8kg so it was cheap to ship over (capable of 580 m3/hr) at ~ $4.5 per kg via 4PX official forwarder then.

Just a normal HDB here.
 

WussRedXLi

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BTW one more thing, you cannot buy a unit and operate it at full fan speed mode.
Some units' medium fan speed mode is also a wee bit on the noisy side, even if the airflow isn't particular high. ie not all APs are the same.

When there is a bout of pollution or when you wanna close windows and switch on the AC (for those who needs filtration to combat dust mite allergens, mold allergens from the aircon coz you don't DIY wash it properly etc), you'd close windows and then you set the fan speed to max/high. If the air is screwed up, it takes longer to filter.

After that you kick into medium or even medium low speed. For sleeping.

That's why i operate 3 APs in my room. I need to achieve approx 250 m3/hr at near-silence levels. Family members are all moderate to light sleepers. Heavy sleepers can get through max fan speed i guess, white noise. :o
 

WussRedXLi

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This is how you size for the room typically.

4 x 5m room, 3m ceiling. Volume = 60 cu metres.

Airflow 300 m3/hr. Air change per hr = 300/60 = 5 ACH Air change per hour. That is fine even though it's at the lower-end for very susceptible/sensitive allergic rhinitis suffers needing extreme low allergen loads in the air. I usually ask people to spec 8 ACH for those.

Note - it's always best to cut down on the source putting out the allergen. eg if it's due to black mold, then you go to the Do you DIY clean your aircon thread and tackle the issue 2 prongs.

You cannot expect 3 big units of X83C Plus @ max fan speed to give you AQI 10 air with just a single lit cigarette in the 5m x 4m room. Won't work that way, coz these air purifiers are not operating in a smooth and turbulent free laminar airflow that is happening in a H14-U15 filtered Class 1000 cleanroom or hospital operating theatre.

Of coz there would be furnitures, bed etc. But it's always good to over-spec. No need to be super exact.

In order to get 300m3/hr airflow and still be able to sleep soundly, you'd need multiple units. Though a single Samsung AX40 might get quiet enough at max fan speed and still achieve ~ 300 m3/hr on the original filter (abut low 200s with the Taobao DIY 25mm x 320mm x 289mm filters and at a lower 2-3dB SPL due to reduced airflow)
 
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WussRedXLi

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Why people say Air purifiers do not work is coz they buy a unit, set it to max for 1st 20 mins, then kick it down to low fan speed coz gotta sleep. Medium/high fan speed cannot sleep.

Low fan speed is like 5-15% airflow only.

What happens then is that the indoor allergens source in the room is still a constant. Aircon FCU spewing out spores/black mold particles at a steady rate. The bed is still being churned and dust mite droppings flying around.

That 5-15% fan speed means that the ACH is way below 1 ACH esp if the air purifiers is under-sized to being with. Don't have to bother with reviews or other posts and wonder liao, i can also confirm and guarantee for you right here right now that the air purifiers is not going to work.


They think that 1st 20 mins clean the room = ok liao. That might help a fair bit with external haze, but for internal source, sorry.

Then you see postings on Facebook, other forums, qoo10 rewviews, EDMW saying these MLM-style gimmicks do not work......Sinkie's money very easy to earn. But issue is really a user problem.
:)

BTW, these allergens are way above 1 micron in size. Taobao H11 filters work work no issue, the difference vs H13 is noticeable but performance hit in CADR (% efficiency and airflow) is ok after factoring in the $$$. TB filters would also work for 0.3 microns at a decent efficiency, measured and verified already by multiple pax.
 
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klarklar

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When using air purifier, is it advisable to close window? But if sleep at night and too low SES to use air-con, how can close window just to use air purifier? Close window means no ventilation.
 

Lucky177

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I have 5 Xiaomi pros. One at each room / area. Decent coverage running at acceptable No smell when operating during the recent burning hazy occasions at night.

Didn’t really closed all windows. Most of the windows closed except kitchen - left open slightly. Still able to keep pm readings down and no smell noticed in living hall and bedrooms.

There’s no hard and fast rule. Sometimes have to close all windows. Sometimes you leave slightly open still able to achieve what you want.
 

WussRedXLi

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When using air purifier, is it advisable to close window? But if sleep at night and too low SES to use air-con, how can close window just to use air purifier? Close window means no ventilation.

Leave a 5mm gap at the window so that there is some incoming/outgoing wind, in addition to the door gaps or MBR toilet door/window helping the exchange.

This keeps CO2 concentration from building up > 2000ppm and making you feel irritable in the morning or have headaches.

Need to close the windows. The next question is, can you tahan the heat even with a fan. I'd bet 99.9% of the pax here cannot do that without AC.
 

WussRedXLi

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I not expert la.

I don’t have either. :)

So what's the CADR for formaldehyde with the green filter for other stuff? Xiaomi never give any figures, they no test? Basically a lot depends on the filter, the AP model is just a part of the "engine".

Maybe need to go dig the private agencies (shanghai, beijing, GZ) and see if they got side info.
 

WussRedXLi

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Some ex info that i could dig out. In short, very few, if not none of the regular air purifiers are very effective if you are talking about a sudden VOC future "attack" aka accident, that is similar to 2013's PSI 401 kind of intensity, just that instead of Particulate matter, we change it now to VOCs.




88HogMt.jpg


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lJNObXJ.jpg



Blueair
TB2AuN4aYVkpuFjSspcXXbSMVXa_!!2347781444.png
 
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WussRedXLi

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WussRedXLi

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Seen this at Robinson's before. Super big. Not sure about Formaldehyde performance though.

TB2U4brcpXXXXbTXXXXXXXXXXXX_!!1792057911.jpg

TB2MDrvcpXXXXaDXXXXXXXXXXXX_!!1792057911.jpg
 

WussRedXLi

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The 352 X83C Plus CADR for Formaldehyde and price/performance ratio is very difficult to beat.

That said, i think at this moment, we can just take the green Xiaomi formaldehyde filter to be 67 m3/hr thereabouts in the Xiaomi 2S.

So 3 units is sufficient for a sudden "attack" for VOC. All pax move into the MBR to sleep, all 3 units move there.
Else 2 units in 2 bedrooms normal days would be nice and doable as well. You can shift 2 units into the MBR in an emergency.

$300 for 134 m3/hr CADR 甲醛 performance?
 
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