Understanding Differential Pressure

In Tip of the Month Video by IAC

You may have heard of differential pressure. Maybe you’ve used or monitored differential pressure in one way or another. However, do you really understand differential pressure?

Well if not, then keep reading.

When you turn the fan on in a baghouse system it creates negative air which results in suction. The two areas where the negative air is present are located in the clean side of the system (above the filter bags) and the dirty side of the system (below the filter bags) as depicted in the illustration below.


As you can see in the above illustration there is tubing equipped to the baghouse which contains two columns of water. When the negative air is present one of the columns of water will rise, while the other will lower; creating a difference in the two columns. The difference in water levels is known as differential pressure.

Why is this information useful?

Knowing the ideal level of differential pressure for your system is key to troubleshooting many maintenance issues. For example, if your filters contain large amounts of dust, this will cause the differential pressure to be greater which may mean it’s time to swap out the filters. The greater distance in water levels could also indicate there is a problem with your cleaning system in your dust collector, or a potential leak in your baghouse. While differential pressure doesn’t tell you exactly what’s wrong with your baghouse, it’s often the first indicator that there is a problem.

Make sure to check your levels frequently.

Because of the importance of knowing the water levels in your system, it is necessary to check them frequently. Differential pressure can be checked using a gauge that is equipped to your baghouse. Be sure to install the gauge in an easily accessible area so that the reading can be viewed often.

If you have any questions about checking your system’s differential pressure or want to know the right level for your baghouse, call and speak with one of our engineers today.

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