Go way back to step #1 and do a short test to see if the hygrometer is telling you the truth in the first place. It could be off by quite a bit. Copy/Paste theft follows-
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Author: SteveRCBid Date: 12/22/2004 11:36 AM Reply
A more accurate method for calibrating your hygrometer is the salt test:
- Take a bottle cap filled with a teaspoon of salt, and add 4-5 drops of water to it. You don't want to saturate the salt, simply wet it.
- Place this inside the Ziploc bag with your hygrometer and seal it up. Let this sit at room temperature for 8 hours.
- After the 8 hours is up, look at the hygrometer, and remember the reading. It should read 75%. If not, you will need to make adjustments.
- Remove the hygrometer from the bag, and allow it to sit long enough to give an accurate reading of the room.
- Adjust according to the reading you remembered. If it read 70% inside the bag, turn it up 5%. Likewise if it was too high.
I usually do a salt test 2-3 times a year.
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Above courtesy SteveR, thank you.
Welcome to the boards ...well worth the price of admission.
Art