PA-II, about 3 years old now. Is this considered a big discrepancy in sensors that I should do I thorough cleaning on? I did try vacuuming and using air to blow it out but not much has changed in terms of AQI value/discrepancy. Wondering if I need to disassemble and do a more thorough cleaning. Thanks for the help!
hope PurpleAir responds to you on this. I’ve always wondered about that myself. If accuracy is a major concern, then the most practical solution may be to replace the sensors entirely since they are swappable and available for purchase separately.
I took the housing off and pulled the sensors out, it wasn’t very dirty, at least with anything obvious. I blew everything out with a bike pump (all I had) but not much has changed in terms of discrepancy between channels. Its possible I need actually take the lasers apart and clean inside but that makes me nervous. I had the same thought as you, I’m thinking of buying a replacement PMS5003 laser (~$20 on amazon) and swapping out channel B (im comparing my results with other sensors near me and B seems to be on the higher side).
Thanks for your reply!
Hi wooper,
Thanks for the post! This is certainly a sizable discrepancy, and I’d generally recommend following our sensor maintenance guide to address this. I understand that you performed a cleaning with your bike pump, but were you able to target those four collinear holes in the unit as outlined in that guide? If there hasn’t been an improvement after doing so, you can take them apart as you’ve mentioned, and that step is mentioned under the “Optional Steps” section of our maintenance guide.
If you’d prefer not to perform a deeper cleaning, a replacement is a perfectly reasonable way forward as Tinashe has mentioned above. You can of course purchase them from a third party if you’d like, though the benefit of getting replacements from us is that we test them in our facility.
Additionally, if you’d like to let us know the device ID of your sensor at contact@purpleair.com or in a direct message to me, I can take a look at its readings and apply downgrades to erroneous channels if necessary.
Happy to help with any additional questions or need for clarification on this!
Hi @ShawnBoyle , tysm for your reply.
I’ve vacuumed and blew out the lasers with special attention towards the collinear holes but the discrepancy between lasers still persists. I’ve taken my sensor down temporarily while i’m troubleshooting and will likely pursue sourcing a replacement sensor. I’ll shoot you a dm to discuss what my next options are. Thanks again!