How to Calibrate a Hygrometer

Getting the correct reading on your humidor is fundamental to keeping your cigars in the right shape. That said, you should ensure your hygrometer is well calibrated and functioning properly before you can use it to measure the humidity level in the humidor.  In this guide, Bottle And Ash comes to your rescue. Here is how to calibrate a hygrometer for accurate readings.

There are many how-to tutorials you can find on the internet to guide you on how to calibrate your humidor. However, not all the guides you find on the internet are the best, and you want to use them carefully.

Why it is important to calibrate a hygrometer 

There is no high-end hygrometer that comes with a high-quality hygrometer to back it up. A hygrometer is one of the most important aspects of any humidor you should look out for when shopping. 

When you have a humidor, you want to ensure the hygrometer you are using is well calibrated so that it gives you the most accurate readings on the humidity level. 

Your cigars are made of natural ingredients, and as such, they are more sensitive to temperature and humidity changes. To prevent mould growth, moisture, and dryness, cigars need to be stored in a controlled environment.

You won’t be able to take care of your cigars if you don’t have a device that can help you test and monitor the level of humidity and moisture in the humidor. 

Calibrating a hygrometer is not that difficult. All you have to do is expose the hygrometer to relative humidity for at least 24 hours and then adjust the readings accordingly.

You can now be confident about the reading on your humidor once you have calibrated the hygrometer. If you run into any abnormal reading, you can tell that it is your storage with a loophole and not the hygrometer.

Calibrating a Hygrometer with Salt Test 

The salt test is one of the most popular methods of calibrating a hygrometer. 

The method consists of placing the hygrometer in some airtight container with salt diluted in distilled water, creating an environment for 75% Relative Humidity (RH).

For the salt test, you will require these items:

  • Distilled water
  • Bottle cap
  • Airtight Container 
  • Pure Salt

You will follow these steps if you want to calibrate a hygrometer using the slat test method.

  • Place an empty airtight container on an empty bottle cap
  • Use the pure salt to fill the cap 
  • Add enough distilled water to dissolve the salt 
  • Add the hygrometer and seal the container for the next 24 hours 
  • Adjust your hygrometer to get the 75% RH 

If you want to obtain the most accurate readings, you should try and get the smallest container and always ensure it has an airtight seal. 

The salt test may not be the most convenient method because of the many drawbacks. It may not give the most precise readings when you calibrate your hygrometer. 

Calibrating a Hygrometer with Boveda

In this calibration method, you have to get a Boveda kit for the job. Boveda kits make it easy for you to calibrate a hygrometer and get some accurate readings. Boveda kits can be used in any hygrometer that you can calibrate. 

Once you’ve bought your Boveda kit, you can proceed with the following steps to calibrate the hygrometer. 

  • Open the calibration kit
  • Put your hygrometer inside the bag
  • Leave the hygrometer to rest for the next 24 hours
  • Adjust your hygrometer 

With Boveda kits, you can perform a two-point calibration for your hygrometer. This process involves using the 75% calibration kit for the next 24hours, making all the required adjustments, and repeating the process once more.

In this method, the hygrometer is calibrated by simply taking the high and low levels into account. This ensures the reading is more accurate across the full spectrum. It is important to note that once you have used the Boveda kits, they won’t be useful or accurate for the next calibration.

How you can adjust and calibrate a hygrometer 

You can adopt multiple methods when calibrating a hygrometer –and all the methods may yield different results. So how do you ensure you get the most accurate results for your hygrometer calibration? Is it possible to adjust the readings on your hygrometer to give accurate readings on humidity?

You can adjust the reading on the hygrometer itself if it comes with a feature that enables this. However, only a high-end hygrometer will have this feature in them. If you are shopping for a low-quality hygrometer, adjusting the readings may not be easy.

Having and hygrometer that is easy to adjust make your work easier. You can opt for brands like Xikar Purotemp hygrometer. It is accurate and can be easy to tune.

When buying a hygrometer, you want to ensure it comes with a dial or anything that you can use to adjust it once you have exposed it to the required humidity. For instance, in the Boveda kit, you can use the tune to turn it to a reading of 75%, after which it will be accurate on all levels. If you want to confirm the accuracy, you can perform a two-step calibration.

In most hygrometer kits, you can simply adjust the reading from a dial found at the back or front. An analogue hygrometer comes with a screw on the rear, turning the needle to the required reading.

How regularly should you calibrate a hygrometer? 

Calibration of a hygrometer is not a one-time thing. You must calibrate and re-calibrate your hygrometer periodically for accurate readings. Your hygrometer requires tuning, and how often you calibrate them depends on the type of technology and brand kit you are using.  

For instance, an analogue hygrometer is made of sprigs and fibres, which will fall out easily and require re-calibration. This is one reason why most people don’t go for analogue hygrometers – the calibration is just too much, which makes them unreliable.

 If you like using an analogue hygrometer, you should calibrate it at least once every six months, so it gets the most accurate readings for your humidor.

A digital hygrometer will tend to last longer between calibrations. You can use a digital hygrometer for years without having any issues with readings. However, it is recommended that you maintain your hygrometer annually to boost its accuracy.

Set a reminder so you can tell when the right time to re-calibrate your humidor is. For convenience, you should buy and digital hygrometer that sets a reminder.

Final Thoughts 

If you are a cigar lover, you want to ensure you store your cigars in the right environment. If you decide to store your cigars in a humidor, you should ensure the moisture, temperature, and humidity level inside is within the required level.

You can only tell if your humidor is at the required humidity level by getting a well-calibrated and tested hygrometer. Apply some of the methods highlighted in this article to calibrate your hygrometer and ensure it gives the most accurate reading on your humidor. With an accurate hygrometer it is easy to keep your cigars in perfect shape and taste.

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