Humi-Care digital hygrometer problems

[megladon8]

So I bought this Humi-Care digital hygrometer off CI.


However I'm having a helluva time calibrating it.

I'm using the Boveda calibration kit with the 75.5% packet inside. The instructions were to place the hygrometer in the bag for 24-36 hours until it gets a stable reading, then calibrate the hygrometer accordingly.

It was in the bag for 36 hours and had a reading of 72%, so I turned the adjustment knob 3 clicks clockwise to make the adjustment, then pressed the "set" button.

However, this resulted in it jumping to 81% RH.

I placed it back in the bag to let it settle down and now, 3 hours later, it still says 81%.


Has anyone else had this problem, or know of a way to deal with it?

Is it a faulty hygrometer? Am I doing something incorrectly?

 

[Jfire]

Dont know the solution but I have three of these exact same ones and they have always read 74 or 75% right off the bat with the calb. packet. How about leaving it in the bag w packet over night and see what it reads?

 

[r3db4r0n]

I would follow Justin's advice, let it sit in the bag for another 24 hours, if there is no change then just turn it back the required number of clicks and then wait another day to see the result. Calibrating hygrometers can be a real pain at times but if you don't take your time with them, you'll only infuriate your self (Believe me, I've done it.

Perhaps it could be that the hygrometer, or even the testing kit (although I don't know of anyone thats ever had an issue with a humidipak, but I can't imagine they are ALL fault free). If all else fails you could either first get another testing kit, return the hygrometer or simply note the difference.

 

[stroke]

well, you turned it three clicks and it went up 9%. Maybe one click is 3%? May be wrong, but it's worth a shot!

 

[megladon8]

I'm starting to think that this style/brand of hygrometer is just incredibly inaccurate.

I have two of these - the one I bought a couple of days ago, and one (without the Humi-Care logo, but the same hygrometer in black) that I've been using for a few weeks.

The black one I had calibrated without issue. Using the Boveda kit it went to 75% RH and stayed there for 2 days, so it was accurate.

However, I put it in the bag again just as a foil, and low-and-behold, after 24 hours it is now reading 78% RH.

So I'm thinking these will have to be used simply as "ball-park range" hygrometers, and not to think that they're accurate to a T.

 

[r3db4r0n]

You may need to let it sit for the full 36 hours to get an accurate reading, its certainly worth trying if nothing else is working. Also take into consideration the temp at which you are calibrating, cold/warm temps can cause a variation in the rh.

 

[Jfire]

I just calibrated these again yesterday(all 3) and after 20 mins they all read 72% w a 72% packet. I think they are very good for the price. At least to me................

 

[Dr. Xikar]

I got this one!

I have three of those hygrometers, they always stay accurate for me... However, the adjustment knob is touchy, that's the only problem! Generally one click is one degree, but sometimes you'll turn it three-4 clicks and it'll jump 5-12 %.

The trick is to calibrate it within a ziplock baggie, that way you can adjust it without removing it from the stable environment. Let it sit in the baggy for 2 days so you know the RH is stable, then adjust and readjust the dial until you're at the right number (75 in this case) and let it sit for a few hours to make sure it stays right.

Other than a finicky dial, it's a great hygrometer, once you get it dialed in, it's set.

 

[Gokian]

100% agree with Dr. Z That is excatly how I do it. They are really really touchy sometimes. You think you turned it one click but it moves 4%.

Try to adjust it through the bag.

 

[r3db4r0n]

Solid advice from someone in the know

 

[Dr. Xikar]

I went through a 3 week period where I thought the thing was crap until I figured out that process... Leave it in the bag for a few days and zero it out to 75% IN THE BAG. (I do salt tests, so it's 75% for me)

That's all it takes