Innovation & Insights
EtaPro® Platform • Video • July 31, 2026
How to Monitor Turbine Inlet Filter Differential Pressure and Automate Alerts
Dirty inlet air filters reduce gas turbine performance, increase compressor losses, and can negatively impact plant efficiency if they are not replaced at the right time. Rather than relying on periodic inspections or operator observations, EtaPRO continuously monitors inlet filter differential pressure and automatically notifies plant personnel when maintenance thresholds are exceeded.
This short demonstration shows how easily a diagnostic can be configured within EtaPRO to monitor inlet filter differential pressure (DP) and generate an email alert whenever the specified limit is reached.
What This Demonstration Shows
In this demonstration, you'll see how to configure a simple diagnostic workflow within EtaPRO that:
- Monitors gas turbine inlet filter differential pressure
- Compares the measured value against an operator-defined threshold
- Determines whether maintenance action is required
- Automatically sends an email notification to designated personnel
- Includes the measured DP value directly in the notification
- Ends the workflow without generating alerts when conditions remain normal
No custom programming is required. The diagnostic is built using EtaPRO's intuitive graphical workflow editor.
Why Monitor Inlet Filter Differential Pressure?
As inlet air filters accumulate dirt and airborne contaminants, the pressure drop across the filters increases. Excessive differential pressure can:
- Reduce compressor airflow
- Lower turbine output
- Increase heat rate
- Reduce overall plant efficiency
- Lead to unnecessary maintenance if filters are replaced too early
- Increase risk if filters are replaced too late
Continuous monitoring allows maintenance activities to be scheduled based on actual equipment condition instead of fixed maintenance intervals.
How EtaPRO Automates the Process
Using EtaPRO's built-in diagnostics designer, users can create monitoring logic in just a few steps:
- Select the inlet filter differential pressure measurement.
- Define an operating threshold (for example, 4 inches of water column).
- Evaluate the measured value continuously.
- Trigger an automated email notification when the threshold is exceeded.
- Include the current DP measurement in the notification.
- Continue monitoring without operator intervention.
This enables maintenance personnel to receive timely alerts whenever filter loading reaches the desired limit.
Benefits
Condition-Based Maintenance
Replace filters when they actually require maintenance rather than on a fixed schedule.
Improved Reliability
Receive immediate notification when differential pressure exceeds acceptable operating limits.
Better Plant Performance
Maintain proper airflow through the compressor and minimize efficiency losses.
Reduced Operator Workload
Automated notifications eliminate the need for constant manual monitoring.
Simple Configuration
Diagnostics can be configured through EtaPRO's graphical interface without writing code.
Typical Applications
This diagnostic is useful for:
- Combined-cycle power plants
- Simple-cycle gas turbines
- Cogeneration facilities
- Industrial gas turbines
- Utility generating stations
- Reliability engineering programs
- Predictive maintenance initiatives
Frequently Asked Questions
What is inlet filter differential pressure?
Differential pressure (DP) measures the pressure drop across the inlet air filters. As filters become dirty, the pressure drop increases, indicating reduced airflow and the need for maintenance.
Can the alarm threshold be customized?
Yes. Users can define their own threshold values based on equipment specifications or operating practices.
Can notifications be sent to multiple people?
Yes. EtaPRO allows multiple subscribers to receive automated notifications.
Does EtaPRO continuously monitor the measurement?
Yes. EtaPRO continuously evaluates operating data and automatically executes the diagnostic whenever conditions are met.
Can similar diagnostics be created for other equipment?
Absolutely. The same graphical diagnostic builder can be used to monitor virtually any measured parameter within the plant, enabling automated condition monitoring for a wide range of equipment.
Video Transcript
How do you know when your inlet filters are getting dirty and how do you automate that notification?
First thing we're going to do is build a diagnostic in EtaPRO. So we're going to start with the start block, and then we're going to come up to a decision block and we're going to connect to them.
We open up the decision block and look at an EtaPRO value and the value we want to find is our inlet filter DP.
We select GT1 inlet air filter DP. We assign a variable A, and then we put in an equation to check if A is true or false. We want to know when A is greater than 4 inches.
Now, we have that decision. The next thing we're going to do is add an action. And within this action we are going to tell EtaPRO to send us an e-mail when inlet filter DP gets over 4 inches.
Who's going to receive the e-mail? And then here we can put the message and what it's going to say. In this instance, we might say inlet filter, DP climbing, and then we can actually show what the variable is.
Now we just simply bring in an end block and we connect these all together.
Lastly, if it's a no, it goes straight to the end instead of sending the e-mail message.
And this is how you can tell if your inlet filter's getting dirty and get an automated notification of when it is.
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See EtaPRO in Action
EtaPRO helps power producers transform operating data into actionable intelligence through continuous performance monitoring, diagnostics, and automated notifications.
Contact us to schedule a personalized demonstration or learn how EtaPRO can improve the reliability and performance of your generating assets.