Topic: PurpleAir PA-II vs AirVisual Pro vs Ambient Weather PM2.5 vs Ecowitt WH41 vs

[WeatherEnthusiastNZ]

PurpleAir PA-II vs AirVisual Pro vs Ambient Weather PM2.5 vs Ecowitt WH41 vs EdiGreen AirBox AI-1001W V3 vs GAIA A12

Background Information
Just in the last few days, I've realized there are a whole heap of neat things that there are sensors for which can be monitored that I previously hadn't realized, an Air Quality sensor being one of them. I had assumed that the all-in-one Weather Station sensor arrays collected data on everything available that their was to collect data on, temperature, humidity, pressure, wind speed/direction, UV and rain.

To my pleasant surprise, I was delighted to find that there are other things that one can monitor as well. A sensor for Lightning, Soil Temperature/Moisture and an Air Quality Sensor. Currently lightning sensors bought independently of a Weather Station are rather expensive, and the ones that can go with Weather Stations are not compatible or included with most Weather Stations. Soil sensors (although cheap) have limited compatibility, as they can't be used with most Weather Stations. Air Quality Sensors however, have more widespread compatibility and can be bought for under $300 (all $ will be in USD). Plus they can be bought independently of a Weather Station with Purple Air, AirVisualPro or EdiGreen/Edimax for about $200-$300. 

I noticed that there isn't nearly as much interest or posts about Air Quality Sensors as there is about Weather Stations and all the other cool things on WXForum. But I'm sure in time, as they become more compatible and or integrated with current & future Weather Stations, there will be growing interest in them. Interest in "Air Quality Sensor" or "Air Quality Monitor" has been growing since 2013 based on Google Trends. https://trends.google.com/trends/explore?date=all&q=air%20quality%20sensor,air%20quality%20monitor
I find Air Quality Sensors super interesting (but there isn't a ton of resources or interest in them as of 2020), so I thought I'd do a quick comparison of the main 6 Air Quality Sensors (that I'm aware of) that can upload their data to a public map (without the user needing any knowledge of API, etc) as at 5 Jan 2020.

This is true example of, the more you research, the more you find and realize what you didn't know. You don't know what you don't know. I intended to have completed this article in about an hour. Well I've now been finding more and more info, and having been going for a few hours now (I'm now completing this on the next day, the 6 Jan).

These are the only 6 Sensors that I’ve found, that can automatically upload their weather data to a public map based on in-built capabilities. In the “Air Quality Sensors” section (this section) on WXforum, by far the Purple Air Sensors (PurpleAir PA-II & the PurpleAir PA-II-SD) are discussed the most (have the most articles about them). Currently there are 37 posts in the "Air Quality Sensors" section. 23/37 are about Purple Air (18/25 of the most viewed posts). 3/37 are about Ambient. 2/37 are about Ecowitt. 6/37 are other.


A few things to note regarding this comparison:

Just because the update interval/rate of an Air Quality Monitor is 10min (vs 10 seconds), is not necessarily bad for battery powered Sensors. Because of the longer update interval, the battery lasts longer.

I use the words sensor/monitor interchangeably.

When I write N/A on the comparison sheet it means "Not Available" not "Not Applicable". I love it when products have very detailed specifications. Once when I was deciding which device to buy between a few different similar electronics, I ended up choosing the one that provided the most specs. This was partly as a token of my appreciation to the company for being transparent with their product by them proving tons of specs.

All 6 sensors are suitable for outdoors.

Note that the large variance in price of $49.99 vs $295.00 is party because the Ecowitt ($49.00) and Ambient ($57.39) Air Quality Monitors are add-ons to existing devices like a Weather Station (which cost quite a bit in themselves). But the other 4, Purple Air, AirVisual Pro, AirBox and Gaia all work completely independently of any other devices.

If you already have an Ambient or Ecowitt device capable of supporting the according PM 2.5 sensors, I'd highly recommend you get it. It's a reasonably priced device that adds a allows for data collection on a whole new metric.


Ecowitt WH41
The Ecowitt WH41 sensor does not work independently, the sensor must be connected to a GW1000 WIFI gateway (http://www.ecowitt.com/wifi_weather/80.html) or one of the HP3500B/WH6006 Weather Stations in order for it to work.

One can buy Ecowitt WH0290 which is very similar to the Ecowitt WH41, except it comes with a console (for about $20 more). The Ecowitt WH0290 only has the 433 frequency.

Connecting the Ecowitt WH0290 to a Weather Station (and thus the internet) is much the same as with the WH41:
"...it can work with our HP3500B and WH6006 Weather Station(Should be at the same RF frequency).
And it can also work with the GW1000 WIFI gateway(Should be at the same RF frequency)."
commented Ecowitt Support in response to a question on amazon on the January 4, 2019. I'm sure their is now additional information since then.

The Air Quality information on the Ecowitt WH0290 can be viewed the on the console (without needing any other device), but it will not upload to the internet/a map unless accompanied with another product (such as above) that allows uploading to the internet. Both Ecowitt devices come with 2x rechargeable batteries. The sensor is not connected to power. It works off solar power as it has a solar panel located on top of it. On sunny days it charges up the batteries and stores the power in the batteries for when it's not a sunny day and thus will use the battery power on those days. If you do not get enough sun, the batteries can be charged ever couple of weeks using a power point (via a supplied charging cord).

Ecowitt has a separate similar ($59.99) device for measuring indoor Air Quality. This device does not use Solar, but instead a constant electricity connection. The Ecowitt WH43.

The Ecowitt WH41 and the Ambient Weather PM2.5 are the same device.


Ambient Weather PM2.5
The Ambient sensor does not work independently, it needs either the WS-2000, WS-5000 or an ObserverIP Module (WS-0800-IP, WS-0900-IP, WS-1200-IP, WS-1400-IP, WS-1550-IP, WS-1600-IP) weather station for it to work. It comes with 2x rechargeable batteries. The sensor is not connected to power. It works off solar power as it has a solar panel located on top of it. On sunny days it charges up the batteries and stores the power in the batteries for when it's not a sunny day and thus will use the battery power on those days. If you do not get enough sun, the batteries can be charged ever couple of weeks using a power point (via a supplied charging cord).
I am unsure if it is able to be used inside.


AirVisual Pro
The AirVisual Pro requires a constant power/electricity connection.
The AirVisual Pro can monitor either indoors or outdoors (I had thought that based on a display photo of the AirVisual Pro screen that shows "Office" & "Outdoors" side by side, it would monitor both indoor and outdoor, but you have to buy 2 AirVisual Pros in order for this to be possible).


PurpleAir PA-II
The PurpleAir PA-II requires a constant power/electricity connection.
The only difference between the PurpleAir PA-II & the PurpleAir PA-II-SD is that the latter one has an SD card (which adds $30.00 the cost).
The Purple Air sensor monitors outdoors, and a separate PurpleAir PA-I-Indoor for $179.00 can be bought to measure indoors.


GAIA A12
The GAIA A12 requires a constant power/electricity connection. On the website it says "The station comes with a 10 meters (33 feet) power cable (5V with DC3.5 connector), so the station should be located no more than 10 meters away from the nearest power source. If needed, we can provide longer power cable (contact us in this case)."


EdiGreen AirBox AI-1001W V3
I don't know what the difference is between the AirBox AI-1001W V2 & the AirBox AI-1001W V3. The specifications are exactly the same, except the V3 can operate in slightly harsher conditions (-10°C ~ 60°C ±1°C) vs V2 (0 ~ 50°C). Perhaps that is indeed the only difference in V2 vs V3. Not being able to operate below 0°C (freezing temperature) does seem like a big flaw, as in winter (depending on where you live) there are sometimes frosts.

The AirBox AI-1001W V3 is described a semi-outdoor. "Must be in well ventilated semi-outdoor spaces such as eaves of a house, verandah, balcony, porch, covered patios, etc". I tossed up between including the AirBox AI-1001W V3 as one of the 6 to compare as some of those placements are not fully outdoors. But I decided to include it, as you can still get a good outdoor reading by placing it in one of those spots such as a verandah.

The AirBox AI-1001W V3 sensor monitors outdoors, and a separate EdiGreen Home : 7-in-1 can be bought to measure indoors.

I could have done a comparison with every sensor such as the GAIA A11 (predecessor to GAIA A12), or the AI-1001W V2 (predecessor to the AI-1001W V3), but the differences were so marginal that I only compared the more updated sensors. The previous versions are still for sale for cheaper prices, but I figured that it made more sense to compare the latest versions.


Page Links Below
The information listed here is what is based off what listed on the product page for each item (there is additional information that I didn't include here as it was hard to do a comparison on due to only 1 or 2 of the 6 different sensors listing info about it. All the info can be found on the product pages listed below:

PurpleAir PA-II
https://www2.purpleair.com/collections/air-quality-sensors/products/purpleair-pa-ii (Info & Buy)
https://www.purpleair.com/map?opt=1/mAQI/a10/cC0#2.13/34.32/63.49 (Map)

AirVisual Pro
https://www.iqair.com/sites/default/files/documents/AVP_TS_INTL.pdf (Info)
https://www.airvisual.com/air-quality-monitor (Buy)
https://www.airvisual.com/air-quality-map (Map)

Ambient Weather PM2.5
https://www.ambientweather.com/ampm25.html (Info & Buy)
https://ambientweather.net/ which can upload data to https://www.wunderground.com/wundermap (Map)

Ecowitt WH41
http://www.ecowitt.com/Other_Sensors/83.html (Info & Buy)
http://www.ecowitt.com/Other_Sensors/11.html (Buy with receiver console)
https://www.wunderground.com/wundermap (Uploads to Wunderground Map, there is also a specific Ecowitt map that you can view if you create an account on www.ecowitt.net)

AI-1001W V3
https://www.edimax.com/edimax/merchandise/merchandise_detail/data/edimax/us/air_quality_monitoring_semioutdoor/ai-1001w_v3/ (Info)
https://www.pcstore.com.tw/i-buy/M28827962.htm (Buy)
https://www.bhinneka.com/edimax-smart-wireless-air-quality-detector-with-pm2-5-temperature-and-humidity-sensors-ai-1001w-v3-sku3328030037 (Buy)
https://www.amazon.com/Edimax-AI-1001W-Wireless-Detector-Temperature/dp/B07ZQSWQWQ/ref=sr_1_3?keywords=AI-1001W&qid=1578256042&sr=8-3 (Buy)
https://airbox.edimaxcloud.com/ (Map)

GAIA A12
https://aqicn.org/products/gaia/ (Info & Buy)
https://aqicn.org/air/view/sensor/spec/pms5003.pdf (Info)
https://aqicn.org/here/ (Map)

There are other places that you could buy them, I've just listed the direct supplier when possible. Some of these devices can be bought on Amazon, and some can only be bought directly through the seller. Also note that they may not be able to be shipped to your country. If you live in the USA, you should be able to get any of them without any issues.

I hope this article is helpful and provides some insight and clarity regarding your choice and decision between the different Air Quality Sensors. There are other Air Quality Sensors (I'll do a separate post about them), but the 6 I've compared here are the only ones that upload to a public map (to the best of my knowledge). And as always, if I've made mistakes in this article, which I'm sure to have done so. Please do let me know, and I'll be sure correct them.

If you are aware of any Air Quality models/monitors/sensors other than these 6 that upload the info to a public map, I'd be interested to know.

 [ You are not allowed to view attachments ]

6 Jan 2020
Updated to add updated/accurate attachment (was showing incorrect values for Ecowitt WH41)
Updated to include "As of 5 Jan 2020, Wunderground does not yet take data from the Ambient and Ecowitt sensors."
Updated to correct the incorrect statement "the AirVisual Pro includes sensors for both indoors and outdoor"
Updated to include GAIA A12 in the comparison thanks to the comment below from dupreezd. I added an updated comparison image, a GAIA section, and changed the references of 5 sensors to 6.
Updated to add in a map link for the AI-1001W V3
Updated the AI-1001W V3 section by removing the line "(only 3 places I could find it for sale)"
Updated the post to include the section "I could have..."

20 Feb 2020
Made the article easy to read by using bold headings
Updated a few details and added in new details

[WeatherEnthusiastNZ]

I've already made mistakes in it, even after an hour of proof checking. I wish I could delete it, and fix the mistakes then re-post it. Even the attachment is wrong.

[dupreezd]

If you are aware of any Air Quality models/monitors/sensors other than these 5 that upload the info to a public map, I'd be interested to know.

https://aqicn.org/products/gaia/
The price for the A12 is actually not bad considering the device have duplicate sensors.

This is what I use to check Air Quality near where I live.
New Years eve, we had an index of 297 at midnight and 172 7:00 am on New years day.
Normal index varies between 19 and 35

[galfert]

I've already made mistakes in it, even after an hour of proof checking. I wish I could delete it, and fix the mistakes then re-post it. Even the attachment is wrong.

You can edit your post. You can then expand the attachments section and uncheck the previous attachment. Then save the modified post. Basically unchecking and saving causes the attachment to be discarded from the post. Then edit it again and add new attachments.

[WeatherEnthusiastNZ]

Sadly, since I didn't post it correctly the first time it loses it's original authenticity, much the same that an edited YT comment does.
But thanks very much for that. It's fixed now!

[Mandrake]

Minor point, worth pointing out but the Ecowitt and Ambient AQM are in fact the same device.
Its just that the Ambient weather stations (WS2000 /WH2902 etc) are keyed to only see the Ambient version of the various sensor including the AQM.

The Ecowitt/Ambient AQM has a solar cell so if used inside will need more periodic recharging via the MicroUSB port

[WeatherEnthusiastNZ]

Good point.

[Glen]

ecowitt also have an indoor sensor wh43, http://www.ecowitt.com/wifi_weather/123.html
from what i can tell the main difference are

• no solar
• usb power on the side of the case, compared to inside the unit with the wh41
• samples at 1min intervals on usb power
• battery power with 2xAA instead of usb power, though sample interval increases to 10mins (same as wh41)
• may not be IPx4 rated? since indoor only

[WeatherEnthusiastNZ]

Interesting. I didn't realize it has so many differences to the main one. Thanks for your post.

[doubleohwhatever]

I've had no issues with my PurpleAir unit. I've had it for almost three years now. The wifi connection works well and you can access the data locally. There's also an extension for WeeWX.

[WeatherEnthusiastNZ]

Thanks for the feedback. It's great to know/hear that it's still working. Things like that will be very helpful for new people who are thinking about getting an Air Quality Monitor.

[Fabius]

Thanks for the great information. I have an Ambient Weather WS-1201 system and their PM25 was the first one I looked at but it's only on their network and only monitors 2.5  It seems to me that the Gaia A12 has the most capabilities for the dollar, redundant sensors PM 2.6 and 10 and has a dedicated air quality map. But my concerns are they seem to be a small operation based in China. How is the support and product quality? Will they still be around next year? I wonder if anyone on the forum is using Gaia A12? I'll post separately asking if anyone does.

[havtrail]

I hope you mean "separately" and not "desperately" as in your post. 

Rich K.

[Fabius]

I have had no success in contacting the Gala A12 people. Since they are in China maybe they are dealing with pandemic issues.