Topic: WH32 humidity reading drifting over time

[genius2_2]

I buyed a Ecowiit GW1002 station in July 2021 and I globally very happy with the performance of every sensor. However I noticed that WH32 humidity reading seem to drifting over time...

For average humidity level (like 40-60%) the reading seem to according to nearby official weather station. But for rainy days, the humidity level must be around 99-100% (like others stations) but I have humidity reading around 88-90%.

If I look back archived data from the firsts months of my station, I had 98-99% humidity reading, but I can't reach this level anymore...

The temperature reading from this sensor continue to be very accurate.

The sensor is in a radiation shield (Ambient Weather SRS100LX Temperature and Humidity Solar Radiation Shield).

Is it that this sensor is aging and became faulty or it need some cleaning where some dust prevent some amount of humidity to reach the internal sensor of the unit?

Maybe I must use the calibration function in the WSView Plus App but this calibration is linear? Because the humidity reading drift is maybe not linear and only appear in high humidity condition?

[Gyvate]

Hi
we had a similar post recently in this forum ....
Humidity means the content of water vapor in the air, which is not necessarily close to 100% when it rains. It's more complex. Temperature and air pressure play a role, whether it is misty or foggy etc. Also the place where your WH32 is located, the air circulation at that place, also inside a protective shelter etc. plays a role. Also, your microclimate there can be quite different from what a nearby (=how far ?) official weather station may measure.

Many protection shields only look good but don't have a good performance (apart from being a shelter against direct humidity, debris (e.g. leaves) etc. One of the main issues is proper air circulation.

This can have negative effects in different ways
- having too high temperatures due to air congestion as compared to an open space
- the congestion will have an impact on the humidity measured as compared to an open space
(i.e. lower or higher humidity is kept in the micro-space of the shelter while it already has changed outside or that value was never or no longer reached inside the shelter - both versions are possible)

Very likely your WH32 outdoor sensor works and reads properly.
If you happen to have a WH31 extra temperature sensor (T/H), you could place it near to your WH32 but only under some rain protection - otherwise in an open space and then compare.

[Platokidd]

I buyed a Ecowiit GW1002 station in July 2021 and I globally very happy with the performance of every sensor. However I noticed that WH32 humidity reading seem to drifting over time...

For average humidity level (like 40-60%) the reading seem to according to nearby official weather station. But for rainy days, the humidity level must be around 99-100% (like others stations) but I have humidity reading around 88-90%.

If I look back archived data from the firsts months of my station, I had 98-99% humidity reading, but I can't reach this level anymore...

The temperature reading from this sensor continue to be very accurate.

The sensor is in a radiation shield (Ambient Weather SRS100LX Temperature and Humidity Solar Radiation Shield).

Is it that this sensor is aging and became faulty or it need some cleaning where some dust prevent some amount of humidity to reach the internal sensor of the unit?

Maybe I must use the calibration function in the WSView Plus App but this calibration is linear? Because the humidity reading drift is maybe not linear and only appear in high humidity condition?

Today is misty and we've had .25" of rain. My high humidify was 99% and now reading 92%. I have the SRS100LX and wh32ep https://shop.ecowitt.com/products/wh32_ep

The SRS100LX in my opinion has worked good with this sensor.