Faulty humidity sensor?

[profzarkov]

Hi
I'm really enjoying my new weather station.
The Ecowitt HP2551 is a great replacement for my aging maplins one.
The only niggle now is the outdoor hygrometer seems to be stuck or just not working.
It was on 90+% for days and so I placed the internal one next to it, waited a bit, then used that value to recalibrate it from the console - a great facility but it still seems wrong.
Ecowitt emailed me to, rather oddly, set it to the default 62%....ok.
The indoor, now outdoor one reads 82% and outdoor one is stuck on this 62%....
I'll give it a few more days ...as it's raining here in Wales!
Anyone else had a sticky hygrometer?
Steve

[profzarkov]

Well the rain has pushed it to 99%..... we'll see.

[water01]

I am wondering if the humidity sensor is in the bit under the Rain Collector which it seems to suggest in Page 14 Figure 5 of the HP2551 manual and if it being affected by rain tips.

I say this because in heavy rain like we have had in the last two days during the rain it will go from 99% to 1% and backup again (1 one off spike that I have eradicated using CumulusMX Spike detection). Other than that mine works OK.

2021-10-28 21:56:22.813 Spike removal: Humidity difference greater than specified; reading ignored
2021-10-28 21:56:22.813 Spike removal: NewVal=1 OldVal=99 SpikeHumidityDiff=50.0

[HansR]

I have my Ecowitt station now running for almost a week and I have the following remarks related to the humidity:

1. The humidity sensor is not in the rain sensor according to the WH40 manual.
2. My observation with my humidity sensor - I configured it all inside where it was a few days - was that it very slowly adjusted itself to the outside humidity. It climbed up from roughly 60% to 98% in the morning in more than twelve hours (humidity where I am is always around 95-100% in the morning and rarely less then 70% in the afternoon in this time of year, actually almost all year). But it adjusts slowly. After several days it became a bit faster but still slow.

So my guess is it is best to have a known hygrometer (a neighbouring station?) and if both are within 4 - 5% of each other (not calibrated) it should be OK.
I don't know what sensor Ecowitt uses, but it is definitely slower than the Davis one which sank deeper and rose faster (I have both stations now in parallel, nice comparison).

[philpugh]

On the HP2551 there is a sensor in the slatted cylinder under the rain gauge. You should be able to remove this cover by unscrewing the two small Phillips screws. I have the WH65 which is very like yours. The sensor (temp/humidity) is enclosed in a protective sleeve. A check to see if this has been damaged wouldn’t do any harm but I would caution against removing it.

[profzarkov]

Ok
It's gone hinky again
Despite shed loads of rain, it's stuck for days on 1%
Looks like I'll have to get the ladder out, remove station and investigate.
Thanks for your suggestions

[profzarkov]

Yes, you're right. The temp & humidity sensor is in a kind of nylon sheath under the rain sensor. Not that good an idea!
I've gently dried it with the hair dryer and have placed the indoor unit adjacent.
Waiting for the two to agree before reinstating.
Not sure how I can make the shielding any better?

IMG_20211226_121713.jpg

Steve

[water01]

See also viewtopic.php?p=159068#p159068

[profzarkov]

Thanks for that. The two sensors seem to agree.
So I've put it all back ...last chance ..then I'll contact the manufacturer

[Gyvate]

That picture shows the outdoor temperature / humidity sensor of the WH65/WS69 outdoor array.
Water flowing out of the rain gauge would (normally) not enter there.
Anyhow, during long rains the humidity is usually very close to 100%.
I guess the pierced cover is meant to dissipate humidity more easily for better measurement and to avoid droplets being created on the sensor surface.
Humidity has to go there in order to be measured though.

A replacement comes together with it !! (sensor only, see below, not the T/H/rain set/kit, which will contain the same sensor and its cover).

WH65_T-H_sensor_replacement.JPG