Air purifier? - Part 2

[imacbie]

WIthout AP nor air con on, open 20cm window
HCHO reading is 0.081
TVOC reading is 0.743

WIthout AP , air con on, window closed
HCHO reading is 0.093
TVOC reading is 0.775

AX40 AP on , air con on, window closed
HCHO reading is 0.109
TVOC reading is 0.815

Don't know what's wrong, the air condition like even worse with the AP on.

HEPA filters will do a great job of capturing particles, but not the VOCs. To also remove formaldehyde and other VOCs, (off-gassing) you will need an air purifier with at least 6 lbs. of activated carbon combined with potassium iodide.

Maybe not enough ac in the samsung

 

[testerjp]

Now with the AP and air con on for a longer time.

HCHO reading is 0.121
TVOC reading is 0.847

what is worrying is the voc and formaldehyde in the air actually increased

 

[imacbie]

Now with the AP and air con on for a longer time.

HCHO reading is 0.121
TVOC reading is 0.847

what is worrying is the voc and formaldehyde in the air actually increased

Assuming window is closed and no air is circulating so the formaldehyde, since is released from furniture and the likes, got no where to escape thus trapping in the enclosed room bah

 

[WussRedXLi]

Very readable paper with good info on UFPs/Ultra Fine Particles.

http://publications.lib.chalmers.se/records/fulltext/165538/165538.pdf

 

[WussRedXLi]

Already mentioned before for that + CO2. Just leave a several mm gap. I have a CO2 meter, already measured and found to be great and works.

Previously in this and the 2015 Haze thread I and another guy discussed or rather argued about this. I mentioned that it's good to leave a gap and not use tape/foam to plug up each and every gap. His reasoning is that even with everything closed tightly, there will still be gaps, evidenced with Chuanz's measurement of PM2.5 increase even with all doors/windows closed and PM2.5 still rose due to high levels externally - ie no need to open gaps. Especially so that CO2 is a gas (gas molecues are measured in angstroms, vs 0.5 microns peak for haze in PM2.5 region).

In the end i bought a CO2 meter and found that we could hit 3000 ppm after like 4 hours of sleep with 1 pax in a small new BTO room.

Note the averaging period of 8-hrs.

http://image.slidesharecdn.com/indoorairquality-121216064710-phpapp02/95/indoor-air-quality-3-638.jpg?**=1355640582

 

[WussRedXLi]

Anyway, humans release some stuff that might be detected by such cheap TVOC meters. So if wanna measure, get out of the room.


Try 1 single drop of rubbing alcohol in your bedroom's table and measure it with the meter, go into the room after 10 mins. You will see that it shoots all the way up and sometimes goes over the meters' limit.

Hence while such TVOC/HCHO meters are probably way off in accuracy, they are still "sensitive", which is good enough for home use

I am not sure if the meter measures TVOC specifically and does a simple conversion for HCHO, based on rough "assumptions". Still would work for general rough use i guess.

Don't worry too much, the levels are not high. And even so, the ASHRAE gives have huge margins.

PS. But the nDIR CO2 meters are pretty accurate, measures the atmospheric CO2 to be nearly correctly vs scientific numbers. More than good enough for home use coz there is always a geographical difference and altitude aspect (they measure on mountains etc).

 

[WussRedXLi]

Bro plastiplotica posted a lasert particle counter + nDIR CO2 + Formaldehyde meter. Uses the UK DART sensor. Search for it. That'd be better for finer resolution responsive readings.

Or search TB for DART sensors

 

[sehsuan]

I think he mentioned he is coming with some new version or something

yes, but because i've yet to get requests for 10 units, it doesn't make sense to order upfront and cough up almost 800 dollars for something that i may end up stuck with.

the earlier generation units i got, are still pretty reliable by any means.

just sharing:

29 march 2016: 442pm Serangoon Central

29 march 2016: 440pm Fernvale Link (70 PM1 /87 PM2.5/97 PM10)

 

[mindgamey]

Ok i got it, posted in post #378 9th Dec.

http://forums.hardwarezone.com.sg/98522765-post378.html


On uncalibrated phone SPL app. Distance @ 1m approx.
(Note : it is uncalibrated, so take the levels on a relative basis, ie 10dB on the phone is not 10dB in real life)

Phone was placed on a chair, unmoved static position

MFresh M8088A
Speed 2 (326 m3/hr) = 36 dB
Speed 3 (520 m3/hr) = 47dB (yes, it's pretty loud)

Xiaomi 2 330 m3/hr = 49dB No it's not a typo. It's very loud.
Xiaomi Auto (presume it's low speed coz it's green LED) = 34 dB

Samsung AX40 high speed (323 m3/hr) = 38dB (official spec = 45dB)


As some of you would recall, previously there was some discussion/debate with bro Mindgamey with regards to the Mfresh M8088A and Xiaomi ver 1 AP's noise levels. Coz I mentioned quite a few times that I would personally not recommend ver 1 esp not in the bedroom due to the noise. There is a lower mode at 271 m3/hr and bro mindgamey measured with a calibrated SPL meter at 54dBA @ 1m (A weighting)

Seriously, with what I have played with the XM2, I would still make the same conclusion though bro mindgamey's opinion is that it's all cool and of coz I'd respect that as with anybody else's opinion as well. But do note that a few folks here and qoo10 reviews have already mentioned that even the Samsung AX40 in HIGH (323 m3/hr) needs a bit of getting used to in the bedroom as well.
The XM version 2 is supposed to be a fair bit less noisy.

I haven't got the chance to access the medium speed coz I believe the app will let you access all the modes, and I don't have time to install and pair up the device. This medium speed at low to mid 200 m3/hr would probably be the speed that you'd be opting to be at for 99.9% of the time. From the button on top, first mode is Auto (beginning of the video above), after that is Sleep mode, after that is the High speed mode (330m3/hr). Jet mode probably is to be selected via the Xiaomi app.


^^^
Edit - Auto fan speed first. Then sleep mode. Then Favourite mode, the icon of a pax with a heart. This fav mode is fan speed settable.

As stated xiaomi High speed is too loud for bedroom or even study room.

Medium speed is good for study room and might be an issue in The bed room for very light sleepers.

I am a light sleep and medium and sounds light white noise.

 

[eriol125]

After messing around with the XM1 n Mi Home app for a few days I still couldnt get it to connect despite the machine have the waiting for connection blinking. Zzzz... tried everything liao

Sent from Motorola NEXUS 6 using GAGT

 

[sehsuan]

After messing around with the XM1 n Mi Home app for a few days I still couldnt get it to connect despite the machine have the waiting for connection blinking. Zzzz... tried everything liao

Sent from Motorola NEXUS 6 using GAGT

Only use 2.4 GHz wifi, and use Mainland China for the app location.

Press and hold the Power + rear button together until you get a BEEP! so that you can try to link it up again.

remember, ONLY use Mainland China as the location for the app! it's hidden in the Android version, and for iOS, i removed the app and reinstalled so that it would ask me again.

 

[eriol125]

Only use 2.4 GHz wifi, and use Mainland China for the app location.

Press and hold the Power + rear button together until you get a BEEP! so that you can try to link it up again.

remember, ONLY use Mainland China as the location for the app! it's hidden in the Android version, and for iOS, i removed the app and reinstalled so that it would ask me again.

Ya, i using 2.4ghz. But the app only have SG, TW n India. Cannot find China leh. Got other version for the app isit?

Sent from Motorola NEXUS 6 using GAGT

 

[sehsuan]

Ya, i using 2.4ghz. But the app only have SG, TW n India. Cannot find China leh. Got other version for the app isit?

Sent from Motorola NEXUS 6 using GAGT

the Mainland China option eventually comes up.... i'm an iPhone user, so i don't have answer for you. but managed to "taiko" do it for my Sis and BIL's Android phones for them before.

 

[eriol125]

the Mainland China option eventually comes up.... i'm an iPhone user, so i don't have answer for you. but managed to "taiko" do it for my Sis and BIL's Android phones for them before.

How u taiko for it lol!

Sent from Motorola NEXUS 6 using GAGT

 

[testerjp]

Ran a few tests, still showing that formaldehyde in the air increase after turning on from 0.81 to 1.21, that's 50% increase. I wrongly assumed that the carbon can decrease such VOC.
My previous recording done in the afternoon actually went up to 1.33.

It's like choosing which way to die from Lung cancer., from dust particles or carcinogen.

 

[mindgamey]

Only use 2.4 GHz wifi, and use Mainland China for the app location.

Press and hold the Power + rear button together until you get a BEEP! so that you can try to link it up again.

remember, ONLY use Mainland China as the location for the app! it's hidden in the Android version, and for iOS, i removed the app and reinstalled so that it would ask me again.

On iOS the location is at bottom when you login.

To change location just log out and login again.

For Android the location is in the settings of your profile.

 

[testerjp]

When i put the device on the AP directly, the formaldehyde reading is 0.045, VOC .585

That's the amount released by the AP?

If add together, the number match

 

[testerjp]

I went for a walk at the park also read 0.06x something. This device spoilt or what.

I've a pantry with high amount of formaldehyde, almost 0.2

Whaf can I do to effectively reduce the amount?

 

[joej]

so its just a matter of taking out the existing cable and plug in the BS1363? the same cable we power up monitors and desktops?

it's the cable that usually comes with laptop power adapters.

 

[joej]

Am still waiting for my XM2 to be delivered but can I confirm if the same 3-pin notebook cable also be used for the XM2?

absolutely. that is all you need