All Plantower laser counters are pretested in PurpleAir facilities.
Replacement laser counters are intended for when a sensor’s previous laser counters fail and cannot be repaired. Make sure to select the appropriate laser counters for your device below, as each type features unique mounting and connection methods.
Dual Laser counters verify each other. It is a great system.
M
Mark Camenzind PhD chemist
Drift of sensors over years
I bought PurpleAir.com PA-II about 2019 and have found very useful. Both Channels agreed well initially, but drifted slowly apart and noise developed over 5 yrs, and eventually data was not longer useful. Autopsied worst sensor B and no spiders, but black plastic photon stop had much white dust. Should use flat back electrostatically dissipative plastics or black anodized etc instead since would give less particle retention. New sensors are running, but about zero hits, AQI 0 for both channels for days in MERV 16 filtered home office. Wish PurpleAir had some statistic readout to estimate reliability
M
Michael Moy
Fast replacement (under warranty)
New counters work fine, hopefully will last longer than my previous set (replaced original after several years), which lasted ~300 days... thanks!
B
Bob Steventon
Excellent support
One of my counters was giving very high readings. After I tried the suggested cleaning routines, Purple Air offered to send replacement counters. I installed the new counters and now my unit is working properly. Great service.
D
Duane Percox
Replacing Laser Counters
I followed the video and the replacement went just as expected. Quality hardware and instruction.
