Have you ever calculated the dew point or the relative humidity for the compressed air system? If no, you’ve come to the right spot. Therefore, you can rest assured about developing an understanding of these measures here and how they will have an impact on the performance of the compressed air system.

Simply put, if you want to remove the condensation problems in the system, you need to calculate the moisture in the air is how much the compressor is capable of holding. Therefore, once you begin to calculate the humidity and dew point, you can rest assured about getting rid of a plethora of problems.

Here, in this feature, we will shed light on how you can maintain the dew point and the different ways you can fix it.


What is the Connection Between the Dewpoint and Relative Humidity?

Although they are staunchly related to one another, still they are both not the same. Simply put, you need to understand each of these terms and see how you can draw a strong connection with each of them.

What is the Dew Point?

Unless you have been living under the rock, you will know that the dew point is the temperature rating at which the water vapor begins to condense into a liquid. Therefore, when the dew point is concerned, everyone is looking forward to measuring moisture in the air. Therefore, if you come across a high reading, it implies that the quantity of moisture in the air is very high.

For your information, the amount of water, which is held in the air volume is related to its current temperature. The warmer air can easily hold more water vapor. So when the air is cooled at a certain pressure for a long time, it will eventually get more saturated.

On the other hand, when the temperature begins to drop, the excess water will quickly transition into a liquid. Therefore, the temperature at which these changes occur is known as the dew point.

This action can be witnessed at atmospheric pressure. The warm air can easily hold an impressive quantity of moisture. However, as the temperature cools down, few are formed on the grass and the other surfaces around. Contrary to this, when the humidity in the air is high, the higher temperature will cause condensation to start. On the other hand, the low humidity will not cause condensation to form until the temperature is below water’s freezing point.

What is Relative Humidity?

Now that you have understood the concept of dew point, you need to develop a strong understanding of relative humidity. It measures how much the air is saturated. Simply put, it will measure the moisture in the air against how much it can hold.

Don’t forget, this is known as a relative measure, so you need to be mindful when measuring it. The RH alone will not educate you about the moisture in the air but rather how close you are to the saturation point.

So when the RH is 100%, the air is fully saturated. If even a single point of saturation enters the atmosphere, it will create an issue. At a rate of 50% RH, the air will continue to absorb more moisture without condensation occurring.

Just like the dew point, relative humidity is directly proportional to the temperature. So at 40 degrees F with around 100% humidity, it has less moisture in the air. This Is why, when you set out on the cooler days, the air will feel much drier. Despite the RH rate being the same, you will still experience drier air. So when the temperature hits the RH at 100%, you will hit the dew point easily. Therefore, you need to be wise enough when understanding the calculations fully in the beginning.  This is why the manufacturers are using the reciprocating air compressor for best results.

The Calculation of the Relative Humidity and Dew Point for Compressed Air

Depending on how much humidity is outside your home, the moisture in the air will vary as well. Simply put, the more moisture, the more I’ll be the quantity of water vapor, which will eventually become a strong part of the compressed system. As explained earlier, the dew point is one on which the system is currently operating. For better understanding, the Dew point is at the PSI at which the system operates. On the other hand, the RH and dew points are in coherence with the air pressure; therefore, when the air is pressurized, excess moisture will quickly be squeezed out. Simply put, the example is equivalent to the water getting out of the sponge quickly.

If you want to visualize this, you can remember that water can easily hold a capacity of air, which is strongly dependent on the current temperature. This means, if 1 m3 of compressed air and 1 mp3 of intake air is done simultaneously, it will eventually hold the same amount of water. However, when compression occurs, a lot of air is squeezed. Therefore, when the temperature is increased by even a single bar, you will eventually squeeze around 1 m3 of air intake and 1/8 m3 into space.

Therefore, it is essential for the manufacturers to have a perspective on the relative humidity and dew point for the current temperatures. Unless they don’t know the operating temperature, it will be hard for them to measure the efficiency of the system.

In other words, they should know about the quantity of moisture in the air and how close they are to the dew reading.

Today, most of the air dryers have dew point sensors that will continually keep a track of the dew points of the system. So now that you have understood the difference between the two, you must have realized how important  they are. No wonder, the dewpoint and relative humidity have been the talk of the town ever since inception. So the next time you are asked about them both, you can educate them.


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