Relative Humidity almost always 99%

[Gina]

Done it again today - even worse! I'll probably be checking it out this afternoon. It was very damp and misty all night and early this morning so I would have expected to see 99%. Very heavy dew - enough to register on my newly modded, extra sensitive rain gauge.

[Gina]

I've brought the tx unit indoors and put my spare in it's place. Of course, the interference measures I added to the old unit are not on the new one but that didn't affect the humidity. The changeover was timed at about 13:45.

I'll be examining the old tx unit later but meanwhile time will tell how well the new one is working. Must admit, the humidity readings (old one) have sometimes made me wonder if the sensor was alright. Though it was a lot better with a better Stevenson screen.

[Gina]

Just had the tx unit under a high power magnifier and carefully examined it particularly around the humidity sensor. I thought the solder joints on the pins connecting the sensor daughter board to the main board looked suspect and when I applied the soldering iron the solder flowed away from the pin - it was dry! I applied some fine solder and the pin surface eventually wetted. I found the same on some of the others too. So I may have fixed it. If it's fine tomorrow I'll swap them back again to see.

Meanwhile, the new tx unit seems to be working fine - the humidity sensor seems to be giving sensible readings.

[wd40]

Gina, I assume these are wave soldered boards, could be some of the parts could be hand inserted and possibly contaminated.

Hard to say what happens over there.

Good information to know.

[Gina]

Yes, I think some of the joints may be hand soldered though the majority are wave soldered. I've found lots of dry joints - seems quite common

Here's the latest plot. New unit from 13:45.

[wd40]

Is it just me or the times two of the three graphs have similar times and the third is inside the margins of the other two.

What about bringing the unit indoors and see how it compares with the console indoor reading for the day.

[Gina]

Is it just me or the times two of the three graphs have similar times and the third is inside the margins of the other two.

The 3 graphs each cover 24 hours and are in time order with a few hours overlap. They could do with the date added to the x-axis really - something for my wish list.

What about bringing the unit indoors and see how it compares with the console indoor reading for the day.

Yes, that's an idea though the indoor humidity doesn't vary much.

I have 2 consoles running on separate PCs one with G-Weather and the other with Cumulus. They agree with each other.

[Gina]

Here is today's last 24hrs worth of outside humidity (from 09:00 yesterday). Very wet in the early hours - torrential rain for a few hours. I would expect the humidity to be in the 90s % but not the continuous 99% (the max) I was getting with the old sensor.

[NarrowAcres]

So I got the new monitor today, but guess what, I'm still at 99% most of the time.
Either I got another faulty unit, or it's a problem with the outdoor unit.

[Gina]

I'm 99% certain it's the sensor not the console. My new outdoor sensor seems to be working fine - much as I would expect the humidity to be. I haven't got round to trying the old one again yet, since resoldering the dry joints.

[NarrowAcres]

So I got the new monitor today, but guess what, I'm still at 99% most of the time.
Either I got another faulty unit, or it's a problem with the outdoor unit.

So it turns out that it was the outdoor sensor giving me the 99%. I ordered a whole new set and set it up and it works with all 3 monitors. It's weird though, all 3 monitors sitting next to one another, I get different indoor readings, but only by a few % humidity or a degree in temp. I guess each one can't have the exact same reading for $100. I find I'm picking up the atomic clock now that the outdoor unit is working, not at all times during the day, but 1/2 the day.
I'll be returning the faulty set to Costco tomorrow. Thanks for the help everyone.