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BTHR918N displaying consistently low RH reading

Discussion specific to Oregon Scientific weather stations
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Posts: 35
Joined: Tue 03 Jan 2017 8:12 pm
Weather Station: OS WMR928N
Operating System: OPi Armbian 5.75 Ubuntu Bionic

BTHR918N displaying consistently low RH reading

Post by SunDial » Tue 03 Jan 2017 9:00 pm


I have WMR928N weather station, which I've owned from new for many years. I've had it running all that time and the RH reading is significantly lower than my other devices with hydrometers, but it seems worse than when I first installed it. I've never really had time to look into it until now. At present, it's reading 23% RH indoors when my other thermos/hydros/baros are reading 49%-51% in the same location (sitting side by side). Barometric pressure and temp seem to have always been accurate enough, and are currently reading 1024mb and 21.4C respectively. I've opened up the sensor and can see a potentiometer soldered to the PCB. Does anyone have a schematic for this sensor or know what sensor the potentiometer controls? I can see the hydrometer sensor, which looks like a HR202L. Could the tracks on this have deteriorated over time?


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