How to Calibrate a Hygrometer
A quality humidor is essential when you’re starting a cigar collection, or you’ve decided to buy a full box from a brand that’s become one of your favorites. Now you can buy your cigars when they’re on sale and keep them fresh until you’re ready to smoke them. Plus, many great-tasting cigars taste even more amazing with the bit of extra aging they’ll receive in your personal humidor.
The key is in keeping your cigars fresh, and any well-made, well-maintained humidor will accomplish that task. Monitoring the conditions in your humidor is an important part of the process and a reliable hygrometer lets you know your humidor and reservoir are functioning correctly.
Do You Need to Calibrate a Hygrometer?
A hygrometer is either a digital or analog gauge that measures the humidity. There are differences between analog and digital hygrometers, but they are designed to perform the same essential function. A number of digital models also feature a reading for temperature. Many humidors come with a hygrometer, but not all. The ideal conditions for storing cigars are 70% humidity and 70 degrees Fahrenheit. You can maintain optimal conditions for storing your cigars by refilling the reservoir in your humidor at a regular interval.
A hygrometer essentially lets you know when it’s time to replenish the reservoir by giving you a humidity reading. When the humidity dips down under 65% humidity, it’s likely a good time to refill the reservoir. The conditions in a humidor will fluctuate depending on the number of cigars you’re storing, the season, and the climate you live in. For example, you’ll need to refill your reservoir more frequently during a cold, dry winter than a warm humid summer. Calibrating your hygrometer ensures that you’re getting an accurate humidity reading.
If you don’t calibrate your hygrometer, you won’t know if your humidor is maintaining enough – or too much – humidity for your cigars. Your reading will be faulty, similar to driving a car with a broken speedometer – you don’t know how fast you’re actually going.
With few simple steps below, calibrate your hygrometer using a simple salt test and rest assured that your humidity readings are spot on.
Calibrate Your Hygrometer with the Salt Test
#1 - Take a clean plastic bottle cap from any standard bottle of water, soda, juice, etc. Make sure the cap has been cleaned and rinsed out. Pour a teaspoon of table salt in the cap.
#2 - Add a few drops of water to the salt in the cap – not enough to completely dissolve the salt, but just enough to create a pasty mixture.
#3 - Carefully place the bottle cap inside a ziplock bag with your hygrometer and zip the seal shut.
#4 - Let the bag sit for 6 to 8 hours. When you return, take note of the reading on the hygrometer before you open the bag. The hygrometer should read 75%. If your hygrometer is reading below or above 75%, you will need to adjust the reading to register 75%.
For most analog hygrometers, simply adjust the needle to read 75% on the gauge by turning the screw on the back of the hygrometer with a small screwdriver. Many digital hygrometers can be adjusted with a button.
#5 - Now your hygrometer will display an accurate reading and you can place it back inside your humidor. Remember to leave the hygrometer in your humidor for several hours before taking a reading, and take note of the humidity reading you get when you first open the box, as the hygrometer will begin to factor in the conditions outside your humidor when the lid is open.
Besides knowing what a fresh cigar feels and looks like, a hygrometer is your first line of defense to make sure your humidor is keeping your cigars in perfect shape. We recommend performing a salt test on your hygrometer once every six months.