PM 2.5 Air Purifier Recommendation

[OneMoreFarang]

Yesterday I think I learned an important lesson with my Xiaomi 3H.

 

A couple of days ago outside the PM2.5 was very high. When I had my 3H on Auto it was running on relative high speed and for me the air in my room seemed to be fresh.

 

Yesterday it was also on automatic. The 3H showed a relative low PM2.5 value. But the air didn't feel fresh. I think the reason was that at that time yesterday the PM2.5 value outside was relative low. So my 3H didn't have to work hard to reduce that. But the overall air quality outside was still bad. So the low automatic speed was not high enough to clean the rest of the dirt out of the air, not just the PM2.5.

I think now I will keep my 3H on manual to be sure it always runs fast enough to clean the air - even if the PM2.5 is not so bad. What really counts is the overall air quality.

[Golden Triangle]

Just been looking on Lazada, had a look at what's available, just ordered ( or the Mrs did on her phone) the 3H, probably be here Thursday, I can now make a judgement call on where to use it as the lounge & bedroom are pretty similar sizes, but I think it will mainly be in the bedroom.

 

I stopped smoking 4 years ago but due to the very poor air quality I sometimes still cough for the first few hours of every day, and if the AQI is really bad I will just wheel it into the lounge shut the doors & windows and be anti social ????

[TallGuyJohninBKK]

Just a word of caution re the Xiaomi purifiers.... Depending on which model you buy and the source you buy from, the units can come with different quality filter units inside.

 

Xiaomi makes several diffferent filter versions, some that are close to true HEPA filters, and others that have lower filtering capacity, down to 95% instead of the standard 99.97% rate that is True HEPA.

 

And from my experience with them, Xiaomi -- either intentionally or because of the CH language translation issue -- isn't exactly transparent on what quality of filters come with any particular unit.

 

[LukKrueng]

2 hours ago, lopburi3 said:

Many units available from both Lazada and Shopee sellers -  but be careful some trying to make a fast baht with very high price.

https://www.lazada.co.th/catalog/?q=hatari+ht-ap12&_keyori=ss&from=input&spm=a2o4m.pdp_revamp.search.go.53f9534b7SwLEq

 

https://shopee.co.th/search?keyword=hatari ht-ap12

do they only have 1 model?

[lopburi3]

13 minutes ago, LukKrueng said:

do they only have 1 model?

Was responding to question about the 3H model - but as pointed out above you need to make sure apples are really apples which may account for some of the huge price difference between sellers - but have not checked closely as am very happy with my Hatari unit.

[Pravda]

On 1/21/2021 at 4:45 PM, tomazbodner said:

Change mode to "heart" and it'll bring it down. Either in app or on the touchscreen.

 

Yes everyone is recommending these and I also have one, but when pollution is really bad, the only setting that will do is heart setting. The problem is its extremely noisy and you can't sleep with this thing on. It boggles my mind why this purifier is being recommended so much. 

[LukKrueng]

28 minutes ago, lopburi3 said:

Was responding to question about the 3H model - but as pointed out above you need to make sure apples are really apples which may account for some of the huge price difference between sellers - but have not checked closely as am very happy with my Hatari unit.

Seems like you are the only 1 with Hatari here, and I think I like the Hatari better than the Xiaomi, but there some info I can't find about it:

1. Can you switch on/off the ionizer? I understand that too much ozone is unhealthy. 

2. I think I saw somewhere that it's good for up to 32 SqM rooms, but I can't find anywhere the air replacement ratio (as in how many times per  hour it completely changes the air).

3. Noise level ?

4. Is there any indicator for current air quality? 

5. Cost of a new set of filters and how often do you replace them?

6. Any other important details I need to know?

 

Thank you ????

[dddave]

1 hour ago, TallGuyJohninBKK said:

Just a word of caution re the Xiaomi purifiers.... Depending on which model you buy and the source you buy from, the units can come with different quality filter units inside.

 

Xiaomi makes several diffferent filter versions, some that are close to true HEPA filters, and others that have lower filtering capacity, down to 95% instead of the standard 99.97% rate that is True HEPA.

 

And from my experience with them, Xiaomi -- either intentionally or because of the CH language translation issue -- isn't exactly transparent on what quality of filters come with any particular unit.

 

I was also going to comment along these lines.  One has to be vigilant when ordering replacement filters, especially online.  My experience is with Lazada.

As "TallGuy" said there are different filters.  There are also one part and two part units, the 2nd part being a core charcoal filter that is separately replaceable.  The cheaper, under B1000 filters are almost always single filters with no charcoal core.  Above B1000 and it's hit or miss.  It took me a while posting questions to the sellers (and trying to make sense of largely incoherent answers) to actually purchase a proper filter WITH the charcoal core included, about B1500. 

I have been told that the charcoal filter is reusable over a long period but I don't know how to evaluate that. 

A friend of mine washes his old regular filter yearly with a hose, dries it and reuses it.  He's done this for 4 years and claims he still gets the same level of purification.

Each to his own.

 

[tomazbodner]

3 hours ago, Pravda said:

 

Yes everyone is recommending these and I also have one, but when pollution is really bad, the only setting that will do is heart setting. The problem is its extremely noisy and you can't sleep with this thing on. It boggles my mind why this purifier is being recommended so much. 

If you had other brands you'd learn something... you buy a new box. 2 months later you think it might be a good idea to stock filters because you got burned before. Shop tells you "old model, contact manufacturer for filter, not sell anymore, you can buy new box". You contact manufacturer who tells you they'll need to import from Japan. Need to wait 2 months and will cost more than new box for each filter.

 

Xiaomi filters are available everywhere and compatible with nearly all the models. You just don't get this elsewhere. Nor do you usually get Wifi connectivity, and built-in air quality sensor. Certainly not at this price.

 

But yes - to your point - Xiaomi wants to keep air quality below 50. We would of course like to see it at 0 so we push it to work harder to bring it down as close to 0 as possible by cranking up the motor speed. It's not designed for that though.

 

Side comment. My previous air cleaners were on 24/7 but had no display with AQI reading. When I turned on Xiaomi it showed 80+. Brought it down to below 10. Turned it off, and waited till next day, and it was over 80 again. The other "TRUE HEPA" 4 stage filter did... pretty much nothing other than eat electricity.

[tomazbodner]

On 1/25/2021 at 1:22 PM, guzzi850m2 said:

I just received the 2 Mi 3C units.

 

I am surprised when plugging them in (one in the living room and one in my office next to the living room) that they both only shows 9 and dropped to 6 now (PM2.5 value) after app 30min running. Doors open to outside in the living room, door to the office/living room open but sliding door from office to garden closed. I am in Pattaya and according to the Air Visual app it's 77 currently?

 

I wrote earlier that 3C is a newer version of 3H, but the truth is that 3C is a bit more quiet and have slightly less capacity, so 3C is good for bedrooms and 3H for living rooms (2 units in larger rooms).

 

 

Mine bring it to about 10% of what outside air quality is at Auto setting. Heart setting (or increased airflow if you have 3H/Pro H) can bring it down further to close to 0 at full blast. But they get loud. Very loud.

[TallGuyJohninBKK]

4 hours ago, dddave said:

I was also going to comment along these lines.  One has to be vigilant when ordering replacement filters, especially online.  My experience is with Lazada.

As "TallGuy" said there are different filters.  There are also one part and two part units, the 2nd part being a core charcoal filter that is separately replaceable.  The cheaper, under B1000 filters are almost always single filters with no charcoal core.  Above B1000 and it's hit or miss.  It took me a while posting questions to the sellers (and trying to make sense of largely incoherent answers) to actually purchase a proper filter WITH the charcoal core included, about B1500. 

I have been told that the charcoal filter is reusable over a long period but I don't know how to evaluate that. 

A friend of mine washes his old regular filter yearly with a hose, dries it and reuses it.  He's done this for 4 years and claims he still gets the same level of purification.

Each to his own.

 

 

One of the things Xiaomi takes advantage of, apparently, was a change in the definition of what constitutes a true HEPA filter by European regulators some time back. They basically made their standard more strict, meaning that Xiaomi filters that used to be classed as HEPA (the E12 rated ones) no longer are.  I found I had some background info on this in my files. So ideally, you'd want an H13 or H14 rated filter using the European standard that Xiaomi uses, and not the somewhat inferior E11 or E12 versions:

 

 

 

Here's some examples of Xiaomi selling the Mi Pro and Mi 2S purifier units with inferior E11 grade filters:

 

 

 

And you'll notice in the 2S product listing above, whomever wrote it got a little bit sneaky by changing the filtering standard they list to a measurement of 2.5 microns in size (which is what the PM2.5 pollution measurement is all about) instead of the tougher and more exacting HEPA filtration standard, which aims to capture up to 99.97% of particles down to 0.3 microns in size.

 

All of the above is not meant to be any kind of recommendation against buying Xiaomi purifiers. The more recent models, especially, are good units for reasonable prices here in Thailand. But it IS a recommendation to be aware there are multiple filter types available that all work in most of their models, and make sure you're aware what you're paying for and what you're actually getting.

 

"Filters meeting the HEPA standard must satisfy certain levels of efficiency. Common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (European Standard)^[4] or 99.97% (ASME, U.S. DOE)^[5][6] of particles whose diameter is equal to 0.3 μm; with the filtration efficiency increasing for particle diameters both less than and greater than 0.3 μm.^[7]"

 

https://en.wikipedia.org/wiki/HEPA

 

Edited January 26, 2021 by TallGuyJohninBKK

[lopburi3]

10 hours ago, LukKrueng said:

Seems like you are the only 1 with Hatari here, and I think I like the Hatari better than the Xiaomi, but there some info I can't find about it:

1. Can you switch on/off the ionizer? I understand that too much ozone is unhealthy. 

2. I think I saw somewhere that it's good for up to 32 SqM rooms, but I can't find anywhere the air replacement ratio (as in how many times per  hour it completely changes the air).

3. Noise level ?

4. Is there any indicator for current air quality? 

5. Cost of a new set of filters and how often do you replace them?

6. Any other important details I need to know?

 

Thank you ????

1.  The ionizer can be turned on/off.  Ionizer itself is not a danger.  They do have a more powerful separate type that likely produces ozone and would be a danger and I never switch that on.

2.  Don't know and suspect that would depend on speed setting but on 2 of 4 setting will bring my 26sm BR down below 10 within 30 minutes on heavy pollution days here in Bangkok.

3.  Very little noise at 2 - about the same as a quite AC - just a little background noise which you only notice when it is off.

4.  No.  I bought a handheld unit that can use outside as well as inside to confirm operation - but it just runs with no issues - have had previous model and this over several decades and no failures.

5.  About 900 baht (it is a single filter with all elements within).  Change every six months although still seems to be working fine for removing dust (but expect good to have new charcoal for smells).

6.  Will turn off on a power outage - but short interruption remains on.  Has remote control but I cover control panel to not have light in BR.  Vac the filter about once a month.

 

[LukKrueng]

13 minutes ago, lopburi3 said:

1.  The ionizer can be turned on/off.  Ionizer itself is not a danger.  They do have a more powerful separate type that likely produces ozone and would be a danger and I never switch that on.

2.  Don't know and suspect that would depend on speed setting but on 2 of 4 setting will bring my 26sm BR down below 10 within 30 minutes on heavy pollution days here in Bangkok.

3.  Very little noise at 2 - about the same as a quite AC - just a little background noise which you only notice when it is off.

4.  No.  I bought a handheld unit that can use outside as well as inside to confirm operation - but it just runs with no issues - have had previous model and this over several decades and no failures.

5.  About 900 baht (it is a single filter with all elements within).  Change every six months although still seems to be working fine for removing dust (but expect good to have new charcoal for smells).

6.  Will turn off on a power outage - but short interruption remains on.  Has remote control but I cover control panel to not have light in BR.  Vac the filter about once a month.

 

Thank you for the detailed answer. This is very helpful ????

[guzzi850m2]

8 hours ago, tomazbodner said:

Mine bring it to about 10% of what outside air quality is at Auto setting. Heart setting (or increased airflow if you have 3H/Pro H) can bring it down further to close to 0 at full blast. But they get loud. Very loud.

I run my 3C in auto in the bedroom, can't hear it. My AC is an inverter type so it goes very quiet when set-point temp is reached.

 

When going to bed last night it was app 24PM when starting and it went down to 15 pretty quickly. When I woke up it was 8.

 

I got mine from some Lazada store for just around 3k a pop so the filters are likely one of the cheaper ones.

 

If I buy 2 more units for the living room it will be the slightly higher capacity 3H and I will get them from Lazada too, with 1 week return but not sure I need them since we live in Pattaya and it's seldom the air is real bad.

[TallGuyJohninBKK]

The other thing that can be done in many cases to increase the efficiency of any air purifier a person may be using is to better seal-off (polluted) air flow from outdoors being able to come inside.

 

There are rolls of adhesive weather stripping tape that can be bought cheaply at local hardware type stores and applied to both door and window frames, and on the lower edges of doors themselves, to limit the inflow of air from outside.

 

Doing that will make it easier on the air purifier(s) inside to keep indoors air at acceptable/desired quality levels.

 

[tomazbodner]

On 1/27/2021 at 9:05 AM, guzzi850m2 said:

I run my 3C in auto in the bedroom, can't hear it. My AC is an inverter type so it goes very quiet when set-point temp is reached.

 

When going to bed last night it was app 24PM when starting and it went down to 15 pretty quickly. When I woke up it was 8.

 

I got mine from some Lazada store for just around 3k a pop so the filters are likely one of the cheaper ones.

 

If I buy 2 more units for the living room it will be the slightly higher capacity 3H and I will get them from Lazada too, with 1 week return but not sure I need them since we live in Pattaya and it's seldom the air is real bad.

True, they are very quiet normally but not when you turn them full blast which is what that heart symbol does by default. When added to app, you can change the "room size" to adjust fan speed, but if you choose the largest (default), it'll sound like a plane taking off.