Topic: Has my VP2 humidity sensor failed?

[bjp]

Hi there,

This forum has been a great help for me before and I'm hoping I can lean on the group's collected experience again.

I believe the humidity sensor on my VP2 has gone out. I'd like to know if there is a way to test and confirm that, and if so which sensor is the correct one to buy to replace it.

Symptoms:

Early this morning my humidity and dewpoint readings began acting strangely. We had some light rain (my rain tipper MAY be undercounting and that may be a related or separate issue) and the temp/humidity/dewpoint readings (as pulled from Weather Underground, exported by my WifiLogger) appeared correct at 70.9F temp, 100% humidity, 71F dewpoint, until 9:05AM this morning.

At 9:10AM reported humidity dropped to 45% and a dewpoint of 48.0F (it definitely still felt like 100% humidity outside).

These numbers remained until the 9:35AM reading.

Since 9:40AM, humidity and dewpoint both report blank (--- dashes).  My reported temperature reading continues to appear correct.

Since then I rebooted the console with no change. I have no values reported for outside humidity, dewpoint, or THW index.

I am guessing this is an issue with the SHT31 sensor, but I believe that sensor also reports temperature so it does not seem to have completely failed. This is quite an old unit with manufacture code A50725A96 which I believe indicates built in 2005, so it is not clear to me if the replacement sensors available at Scaled Instruments (for example) are compatible as they reference post-2006 models.  Can anybody offer some guidance here? Is there a way to clean or otherwise inspect the humidity sensor, or are there replacements available for such an old ISS?

Thank you very much!

[EDIT to add: it appears the moment I posted this, I began to receive humidity/dewpoint readings again. Some quite incorrect ones at 11:20AM of 44% humidity and a dewpoint of 50F; but now shows a realistic 96% and 71F dewpoint. I definitely suspect the sensor is going out so if a replacement is available I am still very interested.]

[davidmc36]

The sensor is the Temp and Hum in one unit. If it is acting like that it sounds done-for. No repair would be possible unless it is simply a poor connection at the ISS SIM Board.

The only issue of pre or post 2006 is you will need to put a 0.5 degree offset in the console for temp if putting newer sensor in older ISS.

[weatherdoc]

With my first VP2 (2005-20015) I had to replace the temp/humidity sensor twice because the humidity sensor would get "stuck" at 100%. It would be intermittent at first and then just stay at 100%. It's easy to swap the sensors out and it was also a good opportunity to take the "beehive" apart and clean everything up.

[ocala]

With my first VP2 (2005-20015) I had to replace the temp/humidity sensor twice because the humidity sensor would get "stuck" at 100%. It would be intermittent at first and then just stay at 100%. It's easy to swap the sensors out and it was also a good opportunity to take the "beehive" apart and clean everything up.

Beehive is a good description.
I had to wrap my shield in vinyl screen because wasps kept getting inside and setting up shop right on top of the sensor.

[weatherdoc]

Yes, when I lived in Florida (I moved to Virginia in 2015), I put a "paint can strainer" over the beehive. The net is fine mesh filter cloth with an elastic band that you put over a paint can to filter out any debris that may get into the can after it's been opened. It not only kept the wasps out but also the Anoles (https://www.bing.com/images/search?q=anoles&qpvt=Anoles&tsc=ImageHoverTitle&form=IGRE&first=1), otherwise known as those little Florida lizards.

[bjp]

Thanks all.

In my case, it's serving more as an anthill than a beehive; once I got out to take the rain cup apart and inspect things the whole unit was crawling with ants.  No additional drop outs on the humidity sensor yet, I'm wondering if ants may have caused a temporary short. But it is very helpful to know that I can use the new/current sensor on my old VP2 with an offset so I will probably get a replacement as a backup. This old one is at least 17 years old at this point so it can't have too much service life left.