MH-Z19C CO2 sensor differs with MH-Z19B
Posted: 26 Nov 2022, 12:56
I use a MH-Z19B sensor for about 2 years connected to a Wemos D1 mini.
Configured in ESP Easy Mega version 20220809-57b0c0c
Serial Port: SoftwareSerial
GPIO<-TX: GPIO-14 (D5)
GPIO->RX: GPIO-12 (D6)
Auto Base Calibration: Normal
Filter: Skip Unstable
Checksum (pass/fail/reset): 43/0/1
Detected: MH-Z19B
Data is send to Domoticz V 2022.2
The above system runs very stable and I trust the values!
Since yesterday I got another sensor. But the new generation, a MH-Z19C...
I build exactly the same system as above. Same board, a Wemos D1 mini. Same version of software, same settings as above.
The conditions of the sensors are the same. They are not in a case, close together, 5 cm from each other, on my desk.
I see different values on the new device, compared to the older one.
It's values on the new sensor are about 250 to 350 ppm higher. The temperature is most of the time the same compared to each.
What to do?
Q1: Is it possible to force calibrating the new one? How to do that?
Q2: What is the meaning of the U-value? It is 0 on the old, around 25850 on the new one..
Configured in ESP Easy Mega version 20220809-57b0c0c
Serial Port: SoftwareSerial
GPIO<-TX: GPIO-14 (D5)
GPIO->RX: GPIO-12 (D6)
Auto Base Calibration: Normal
Filter: Skip Unstable
Checksum (pass/fail/reset): 43/0/1
Detected: MH-Z19B
Data is send to Domoticz V 2022.2
The above system runs very stable and I trust the values!
Since yesterday I got another sensor. But the new generation, a MH-Z19C...
I build exactly the same system as above. Same board, a Wemos D1 mini. Same version of software, same settings as above.
The conditions of the sensors are the same. They are not in a case, close together, 5 cm from each other, on my desk.
I see different values on the new device, compared to the older one.
It's values on the new sensor are about 250 to 350 ppm higher. The temperature is most of the time the same compared to each.
What to do?
Q1: Is it possible to force calibrating the new one? How to do that?
Q2: What is the meaning of the U-value? It is 0 on the old, around 25850 on the new one..