Is washing the flux off with isopropyl alcohol suggested on both the pre-assembled boards and/or the DIY boards?
I used typical leaded 60/40 rosin core solder and then used isopropyl alcohol to clean the flux with a DIY Pro Kit 4.2 , but noticed the datasheets on at least the Senseair S8, SGP41, and SHT31 sensors mention that washing and cleaning agents should be avoided. Wondering if the sensors are damaged because they were exposed to isopropyl alcohol.
@krhainos You can wash the PCB first after the soldering then wait for a while then insert the sensors, it should be fine!
Hi @Alan_Ng – I’ve washed the individual preassembled PCB’s with sensors on them too (probably a bad idea in hindsight). Isopropyl alcohol probably has ingressed into the sensor modules themselves. Is it possible, that the sensors are compromised?
The reading appear to be fine, and I purchased a second pre-soldered kit just in case.
@krhainos I always clean the PCB with Contact Cleaner or PCB Cleaner which is specific for electronic PCB soldering. I also use Isotropy alcohol for cleaning but it looks like not so effective.
I have use the alcohol to clean the CO2 sensor case due to some finger prints on it before, now I use Wet wipes only.
Since I need to confirm the CO2 sensor is function normal, I will use software drink with CO2 for testing.
I do not find the sensor having problem during the Hi and Lo level CO2 is applied.
If you cleaning the PCB and the sensor outside only, I think it do not damage the sensor.
If the alcohol is going inside the sensor directly then it may be a problem.
Also the alcohol will be evaporated so quickly, so it should not be a problem.
Lat time I use High concentration of alcohol to check my TVOC sensor (no protection case )around that I was concerned.
After the testing the sensor is working fine with low concentration level of alcohol can be detected with low value reported normally.
If you do not physically contact the sensor itself, I mean the real sensor located inside the sensor case. I guess it is fine!
In my conclusion is that all sensor will be safe if the testing media is not directly contact inside the sensor components with a very high concentration that is okay. Since all the PM sensor and CO2 sensor have a ventilation to get the air in and out through the sensor hardware for the getting level data, so it should be fine!
@Alan_Ng Thank you very much for your thorough response! The sensors that may have had contact with isopropyl alcohol are the Senseair S8 (CO2), the SGP41 (TVOC/NOx), and SHT31 (temp/humidity). Since they appear to be working fine, I think I can conclude that the sensors are working just fine.
Thanks again!