What options for CO2 sensor?

Hardware
21

ESPHome supports the MH-Z19 CO2 sensor. Currently waiting for module to arrive from AliExpress right now. Less than $20 USD.

1 Like
22

did you get it to work with ESPHome? all the cheap ones I can see are the Z19B variant and from the ESPHome docs it’s unclear to me if it would also be supported.

23

Yes, it works very well with ESPHome and Home Assistant

MH-Z19 CO2 Sensor Graph

esphome:
  name: co2sensor
  platform: ESP8266
  board: d1_mini_pro

wifi:
  fast_connect: true
  domain: .local
  power_save_mode: NONE
  reboot_timeout: 5min
  ssid: "mySSID"
  password: !secret
  use_address: co2sensor.local

# Enable logging
logger:
  level: debug

# Example configuration entry
uart:
  rx_pin: D3
  tx_pin: D2
  baud_rate: 9600

sensor:
  - platform: mhz19
    co2:
      name: "MH-Z19 CO2 Value"
    update_interval: 30s
    
# Enable Home Assistant API
api:
  password: !secret

ota:
  password: !secret
3 Likes
24

I suck at soldering. Are there any modules that just clip on or always soldering that has to be done?

25

There are modules that have pins already soldered to them. Search AliExpress.com for MZ-Z19 sensor and you’ll see them. Then you can use push-on Teflon jumper wires to connect them.

26

I checked Ali but only found with pins on one side. Sufficient? Also, what to connect it to? What is preferred? Esphome can be flashed to a couple of different devices or?

27

I used this. Works perfectly :slight_smile:

28

i went the easy way: ESPhome supports the SCD30 and MH-Z19 sensors.
I have the Grove version of the scd30.
$4 for the nodemcu
Takes less than 15 mins to connect and configure.
Instantly gives you sensor.* entities in HA with the esphome addon.

image
image1280×958 295 KB

3 Likes
29

Hi,

I am new to HA and also looking for an easy way to add a CO2 sensor to my house. Will any SCD30 sensor work, or must I stick with the Grove version? I did some quick search and the Grove version takes very long time to ship to where I live (Germany).

30

Any scd30 should work if you wire it correctly.
Just get an esphome mcu, like nodemcu, and wire it.
Then do software setup for esphome

31

many thanks for your hint, very much appreciated. I ordered nodemcu and scd30 on aliexpress, should get them in mid Nov.

Since all of HA, EPShome and nodemcu is new for me, it will certainly take me more than 15mins :slight_smile: If you happen to have a link to a guide, it would be great.

32

This is the guide I followed:

Copy-paste template for the scd30:

33

thank you, much appreciated.

34

What about this one? “Carbon Dioxide CO2 Detector Air Quality Tester Formaldehyde Detector”

35

hell no, that does not actually detect carbon dioxide it detects VOC and fakes a CO2 level

a functional CO2 sensor, literally just the sensor component, costs at least $20 usd, and those are the cheap chinese ones. The SCD30 is the really the best price you can get for an accurate sensor with auto calibration and temp/humidity compensation. Other quality sensors are $100 to $120 (I have checked them all)

For reasons to get the SCD30 over the cheap chinese ones, see this post:

1 Like
36

I found this awesome tutorial…

sensor all the things!

https://tinkerman.cat/post/sonoff-th10-th16-sensors-displays-actuators

37

This one Tuya compliant:
CHF 51.54 49%OFF | Tuya WIFI CO2 Meter CO2 Detector PM2.5 Temperature Humidity Sensor Multifunctional Air Quality Monitor Carbon Dioxide Detector


Someone tried?
38

The listed range of detection, combined with the price range, implies an MH-Z sensor for CO2

39

There is now a Zigbee 3.0 Co2 sensor.
I haven’t yet got it to work with Home Assistant.
It shows Temp and Humidity, but not CO2, I’m guessing it needs a quirks file creating.
(ZHA Handler for Zigpy)

I’ve requested it:

1 Like
40

quite expensive at £139 !