[Steve1506]

I now have my AQM working but I am getting a very high CO2 reading around 2000 when operating in my workshop. Is this to be expected ??

Seems a very high value even when working indoors.
Please check in the software if the selected model corresponds to the model of your CO2 sensor. There are two models, A and B.

Werk,
Thanks for the reply the label on the sensor says its a MH-Z19B but I have tried changing the software and get similar results. Reading the serial monitor it seems ti be fine then gives a high reading and stays that way. See data below. Do you think the sensor is faulty.

set as MH-Z19

Code:

 WeatherDuino 4Pro Air Quality Monitor v8.0 b001 Please wait 30s Configuring CO2 Sensor Setting measurement range to: 5000 FF,99,1,0,0,0,0,0,66, 66,66 Measurement range changed! Disabling ABC Funtion Reseting Sensor EF,AF,29,FE,0,0,0,1,0, Calculated crc: 29 Wrong reply from CO2 sensor! FF,86,1,9A,3B,0,0,0,A4, Calculated crc: A4 CO2 read: 431 - Temp: 19 FF,86,1,9A,3B,0,0,0,A4, Calculated crc: A4 CO2 read: 431 - Temp: 19 FF,86,1,9A,3B,0,0,0,A4, Calculated crc: A4 CO2 read: 431 - Temp: 19 FF,86,1,9A,3B,0,0,0,A4, Calculated crc: A4 CO2 read: 431 - Temp: 19 FF,86,1,9A,3C,0,0,0,A3, Calculated crc: A3 CO2 read: 431 - Temp: 20 FF,86,1,9A,3C,0,0,0,A3, Calculated crc: A3 CO2 read: 431 - Temp: 20 FF,86,1,9A,3C,0,0,0,A3, Calculated crc: A3 CO2 read: 431 - Temp: 20 FF,86,5,AC,3C,0,0,0,8D, Calculated crc: 8D CO2 read: 1526 - Temp: 20 FF,86,5,9B,3C,0,0,0,9E, Calculated crc: 9E CO2 read: 1508 - Temp: 20 Init MH-Z19 Ended Waking up the dust sensor... Reading will be done 40s later. Reading the dust sensor... PMS7003 readings: PM2.5: 2.39 ug/m3 PM10 : 2.39 ug/m3 PM2.5_1H_Avg : 2.39 PM2.5_NowCast: 2.39 FF,86,4,FE,3D,0,0,0,3B, Calculated crc: 3B CO2 read: 1302 - Temp: 21 Set as MH-Z19B  WeatherDuino 4Pro Air Quality Monitor v8.0 b001 Please wait 30s Configuring CO2 Sensor Setting measurement range to: 5000 FF,99,1,0,0,0,0,0,66, 66,66 Measurement range changed! Disabling ABC Funtion Reseting Sensor 21,10,1C,FC,0,1,0,71,0, Calculated crc: 66 Wrong reply from CO2 sensor! FF,86,1,9A,3E,0,0,0,A1, Calculated crc: A1 CO2 read: 431 - Temp: 22 FF,86,1,9A,3E,0,0,0,A1, Calculated crc: A1 CO2 read: 431 - Temp: 22 FF,86,1,9A,3E,0,0,0,A1, Calculated crc: A1 CO2 read: 431 - Temp: 22 FF,86,1,9A,3E,0,0,0,A1, Calculated crc: A1 CO2 read: 431 - Temp: 22 FF,86,1,9A,3E,0,0,0,A1, Calculated crc: A1 CO2 read: 431 - Temp: 22 FF,86,1,9A,3E,0,0,0,A1, Calculated crc: A1 CO2 read: 431 - Temp: 22 FF,86,1,9A,3E,0,0,0,A1, Calculated crc: A1 CO2 read: 431 - Temp: 22 FF,86,3,ED,3E,0,0,0,4C, Calculated crc: 4C CO2 read: 1056 - Temp: 22 FF,86,3,E7,3E,0,0,0,52, Calculated crc: 52 CO2 read: 1050 - Temp: 22 Init MH-Z19 Ended Waking up the dust sensor... Reading will be done 40s later. Reading the dust sensor... PMS7003 readings: PM2.5: 0.00 ug/m3 PM10 : 0.68 ug/m3 PM2.5_1H_Avg : 0.00 PM2.5_NowCast: 0.00 FF,86,3,FE,3E,0,0,0,3B, Calculated crc: 3B CO2 read: 1038 - Temp: 22

Steve D

I have now fixed the problem by changing the resolution to 2000ppm in the software . I now get a reading of 399 outside in the air and 430 in my office. The AQM has been running for a few hrs. Not sure why this fixes it as the sensor does say it is good for 0 to 5000ppm

Steve D