Air purifier?

[WussRedXLi]

****, I smell my just washed and wore once yesterday polo shirt, and it smells of smoke.

 

[mindgamey]

Long time ago when i was still playing with hifi, i know that every doubling of the speakers/2X increase in power = +3dB.


Lets not talk about the LG LA-Q379/Samsung AX40.

We talking about the A50 and Xiaomi, which you have measured as 50dBA and 61dBA. And we treat it simply that we put into a normal room and assume little phase cancellation since it is "white noise" (it's definitely not sine wave! )

1 x A50 = 50dBA
2 x A50 = 53dBA
4 x A50 = 56dBA
8 x A50 = 59dBA
16 x A50 = 62dBA

You can safely saw that 10 units of A50 clustered together, in real life in a real big room sited at one end, sounds nearly the same as 1 x Xiaomi

Wish you can do the same for the AX40, but i don't reckon that you have one.


May I shd get a SPL meter from TB. Old one spoilt liao.

You are right.
2 sources with same noise level when placed next to each other will add 3dbA to the combined noise level.

However I dont think anyone would place 2 AP next to each other, they would spread it around the house.

The xiaomi can't be compared with the Sharp A50 which cost me 50% more ($300 vs $450+ non haze period price).

For the same price for the xiaomi you can get AX40, which I wanted to buy at first but u it only has 2 speed modes is a deal breaker for me, the LG is probably better. I won't gun the xiaomi in jet/high mode or my A50 in high speed unless AQI reaches sub 300+.

So it depends on application, LG is a versatile AP and xiaomi can do a lot of thing you wish an AP can do (remote control, actual air quality reading

Anyway xiaomi can be scheduled to at specified time (eg. before reaching home after work day) is very useful.

On the side note, xiaomi uses sharp dust sensor for its reading.
Googling the model(GP2Y10) and found the sensor is an optical sensor.

 

[otacon]

The AX40 only consumes 0.14kWH of electricity after being powered on High mode for 6 hours straight; that translates into $.02849 (based on Oct's tariff of $0.02035/kWH).

Good info here

 

[Lucky177]

So far, my hepa filter in my small Hitachi AP also got smell now. But that's one year old haven't changed liao.

The other recently changed hepa filter in my Honeywell still no smell.

The other old hepa filter in my the other Honeywell still no smell. Think more than a year. Probably now I more "guai". Go changed my prefilter recently which was long long overdue. LOL

The living hall one I no go smell, so not sure.

This year no horse run. All the years I no experience chao tar smell from my APs despite usually "overrun" my filters. Hehe. Only this year got chao tar smell. Haha.

All above APs located in West region. Those got monitor will know what's the readings over there.

Ps: If those using AX40 etc, actually no issue...since filters at taobao so cheap. Buy a dozen and change also no problem. Still cheaper.

Sent from Android Mobile using GAGT

 

[ralliart12]

That means 0.023kWh...

How did you derive this 0.023kWh?

 

[nwh_sg]

****, I smell my just washed and wore once yesterday polo shirt, and it smells of smoke.

I avoided hanging out clothes during the past few heavy haze days. The thought of smoked clothes deters me. lol.

 

[Astro]

Qoo10 Daiso selling 5000gmd for 238 includes shipping

 

[derazor]

http://news.asiaone.com/news/asia/indonesian-government-confused-over-singapore-helps-haze-situation

 

[WussRedXLi]

For the same price for the xiaomi you can get AX40, which I wanted to buy at first but u it only has 2 speed modes is a deal breaker for me, the LG is probably better. I won't gun the xiaomi in jet/high mode or my A50 in high speed unless AQI reaches sub 300+.

Actually, especially in this 2015 haze season, airflow/CADR/whatever-you-wanna-call-it, output is king. I have currently 7 APs around my house (and 3 others in parents and grandma place) and I found with my meters that even with 7 APs in which 4pcs are 300+ m3/hr machines,then at 300+ ug/m3 (last Wed-Thur) concentration, high fan speed is barely sufficient. My house is not leaky type, but for normal living, you just cannot afford to keep all doors/toilet windows closed......and you need to air things every few hours.

For 2014 haze, Samsung AX40 in the living room is somewhat ok only.

Or maybe it's coz my standard is more like 10 ACH, for allergic rhinitis sufferers. But no matter what, do not go below 5 ACH.



The saving grace for the AX40 is that it's silent (45dBA) at high speed, and consumes very low energy at that speed (slightly below 30W), and still does 300+ m3/hr airflow.

The LG 459 or 379 in High speed (1 level below Turbo) consumes 20 watts, if I remember my measurements correctly. At an airflow output of 200 m3/hr and probably just 40 or 41dBA.

But its Turbo mode SPL is fairly noticeably higher than the AX40. I suspect it's about 47dBA.
It's also a bigger unit than the AX40. I've got 3pcs of those, is only coz they are so cheap. First one $220 brand new retail (display set), second set 379 is used at $60. Third set BNIB from carousell at $120.
Not because I like it better than the AX40. You can't find AX40 deals on gumtree/carousell or even SG retail.

On the side note, xiaomi uses sharp dust sensor for its reading.
Googling the model(GP2Y10) and found the sensor is an optical sensor.

Yeah I have one of those Sharp IR diode sensors for air quality readings, only used it for 2014 haze season. This year I am using laser particle counter based ones liao, much more sensitive for PM2.5 values.

But the Sharp is still ok, just that the lower-level ug/m3 sensitivity/resolution is not there.....and mainly it is sensitive above 1 micron so basically you are reading the PM10 readings, which at least in Singapore bears a pretty close curve to PM2.5. (check NEA 24-hr PM2.5 and PM10 values for N S E W C)
But if you are using for higher-level ug/m3 "haze application", that is fine.

Indon biomass haze in Singapore has a particle size range from 0.15 microns to 1 micron, and have a very large peak at 0.5-0.6 microns range.

I nearly got a Sharp 840 and 850 for just $100 for both.
Wanted to get a Shao C100, which is something like the A50, $70. But then I don't like the humidifier models due to their large size.

I have a 840.

 

[nwh_sg]

Err...This is the Air Purifier thread leh...how come its not the place to post such question? Not trying to be funny here lar..I am asking because I am considering getting another AP and so am considering whether to get the LG AP instead of the Samsung AP.

I recalled that you did a comparison and the Samsung AX40 AP came out to be the (slightly) better option compared to the The LG AP because the Samsung filter is more readily available and can be bought from TB.

Hence if the LG filter can really be washed and re-used, then LG AP would have been the better option right?

Just wanted to verify the claims made in the marketing materials against reviews from people (such as yourself) who have actually used the AP.

Bro,
This is the instruction for washing the LG filters (extracted from manual):

For Hepa filter, WRX and other bros advised that washing it will not help and may compromise its effectiveness/integrity.

For carbon filters, judge if it is really washable from googling (using keywords such as reuse activated carbon/charcoal) .. example:
How to Reuse Activated Charcoal
Most would require 'baking' the carbon at a high temp. So it would not be practical to do that to the filter.
That being said, to satisfy my own curiosity, I may wash it and sun it after its "COE expired".

 

[WussRedXLi]

Err...This is the Air Purifier thread leh...how come its not the place to post such question? Not trying to be funny here lar..I am asking because I am considering getting another AP and so am considering whether to get the LG AP instead of the Samsung AP.

I recalled that you did a comparison and the Samsung AX40 AP came out to be the (slightly) better option compared to the The LG AP because the Samsung filter is more readily available and can be bought from TB.

Hence if the LG filter can really be washed and re-used, then LG AP would have been the better option right?

Just wanted to verify the claims made in the marketing materials against reviews from people (such as yourself) who have actually used the AP.

Ok, I tried washing my Sharp 840/A40 HEPA just now.
It's a used one that I used quite a fair bit, that I kept in the storeroom, for unknown reasons. Sharp filters are not meant to be washed.

The water did not turn black, just slightly grey even after trying to "Destroy it in the basin". The filter is quite nicely used.

Hope that proves that HEPAs are not meant to be wash.
Even if you did not manage to destroy it, the PMs won't come out.

Morning bro wuss

I ordered the cheap hepa from TB going to arrive soon, and also the cheap filterate sheets since I can't the 3M anywhere

You have prob answered this before, pai sei confirm again:

For living room fans mine are all the type where the motor is a bump at the back, so I place the hepa on the front and secure it somehow? (The product page shows people tying it to the back of the fan, but impossible for mine leh)

The filterate piece better to place on the back or the front?

I'm thinking some fans use filterate, some fans use hepa... Experiment a bit

Edit: I just realized that since the hepa I ordered is the loose kind that can be cut, I can cut into smaller pieces and still cover the back of the fan around the motor... Brain a bit slow, haha

Think should work right?

HEPA at the front of the fan. 3M Filtrete can be front or back of the fan.
But after reading the particle count values on that particle counting tmblr blog, the CADR of the HEPA + fan is pretty low compared to a proper AP.

Even the cannon is not fantastic. It is also quite noisy and very energy inefficient.

But during hazy days like these, it'd do.

I'd recommend the 3M Filtrete, it works ok. But not exactly cheap.

 

[aCidz]

It's another seller. The 300 x 300 x 25mm one that costs RMB26, some 百姓 HEPA, or common people HEPA.

The main factories manufacture more than 100 million HEPA filters annually in such a size. The production lines are massive. That's why can be so cheap.

China air purification is a 14 billion USD market, from a source that read.
Now they have standards and test labs/agencies to try to give consumers a good unbiased source of reference, else it got messy a while ago.

Thanks. Found it

 

[WussRedXLi]

How did you derive this 0.023kWh?

Divide by 6. He mentioned 6hrs.

But just measure it with a DMM ba, VAC and current.

I measured 19W for the Samsung AX40 + 25mm depth HEPA, that 26rmb one. And at 240 m3/hr airflow.

With a more restrictive filter, the wattage drops, motor speed auto drops.

 

[Tryg2015]

Ok, I tried washing my Sharp 840/A40 HEPA just now.
It's a used one that I used quite a fair bit, that I kept in the storeroom, for unknown reasons. Sharp filters are not meant to be washed.

The water did not turn black, just slightly grey even after trying to "Destroy it in the basin". The filter is quite nicely used.

Hope that proves that HEPAs are not meant to be wash.
Even if you did not manage to destroy it, the PMs won't come out.



HEPA at the front of the fan. 3M Filtrete can be front or back of the fan.
But after reading the particle count values on that particle counting tmblr blog, the CADR of the HEPA + fan is pretty low compared to a proper AP.

Even the cannon is not fantastic. It is also quite noisy and very energy inefficient.

But during hazy days like these, it'd do.

I'd recommend the 3M Filtrete, it works ok. But not exactly cheap.

Just checked at amk hub fair price xtra. OOS... Salesman said check again on wed

 

[hOp3SoT]

Qoo10 Daiso selling 5000gmd for 238 includes shipping

tats the cheapest i had seen!

 

[sacredrays]

tats the cheapest i had seen!

but ship using qxpress.. not fedex/dhl

 

[WussRedXLi]

Ok, maybe I would share a paragraph about 2015 Haze here.

I have about 1900 m3/hr airflow from the 7 APs in my own house, including 3 x 3M Filtrete for the aircons which I'd estimate 3pcs = about 100 m3/hr clean air. Floor area = 95 sqm.

What I noticed about the 200 ug/m3 peak is that the PM load is really high and it really affects the air quality in the house. I mean, your toilet windows usually can't be closed (though I close them whenever it gets close to 300 ug/m3 external) and the yard door usually is left slightly ajar coz others need to do laundry and put dirty clothes.....hence if someone forgets to close properly, the internal ug/m3 concentration sky rockets. Or when you open the main door to throw the rubbish, or someone leaves the house.

What I noticed is that 1000-1900 m3/hr of airflow is just barely enough. I mentioned 1000 ug/m3 is when some of the machines would be operating in medium speed, due to noise. Barely, as in yes ..... after you clos the yard door and toilet windows properly, after 1hr the levels would go below 20 ug/m3. I can hit 5-10 ug/m3 after a period. But with regular acitivities, it usually hovers around the 20-30 ug/m3 range.

In my house, I have 1 x 18" fan and 1 big air circulator operating in low speed to circulate the air around.

 

[WussRedXLi]

After the haze season, if those folks are interested, you can also aim for the Midea KJ30FE-NV.

I got I on Sep 11th polling day for $100 Brand new in box, delivered. I regularly see folks selling for $99, before the haze season of coz.


The original filter on TB is just RMB99.

 

[WussRedXLi]

Bonus pic

This is the LA-Q37SB. The PS-R459 is silver edge.
(and also cannot switch off the LED lights)

 

[WussRedXLi]

小米

Noise (dbA): 61, 54, 46, 44, 43
Flowrate m3/h: 406, 271*, 174*, 93*, 68*


Ok I calculate the ACH for those interested.


5 ACH / Air Change per Hour. Don't worry about the furniture in your room taking up volume, just leave it and let it be....

2.9m HDB ceiling.

406 m3/hr. 61dBA
Supported area = 28 sqm

271 m3/hr 54 dBA
Supported area = 18 sqm (typical new BTO master bedroom)

174 m3/hr 46 dBA
Supported area = 12 sqm (typical new BTO bedroom)