Gas turbines don’t usually fail dramatically. There’s no explosion, no warning siren. More often, it’s a gradual slide — a small drop in efficiency here, an odd vibration there — until one day the machine forces your hand. By then, the damage is done and the cost is real.
After 27+ years of working alongside maintenance teams across power utilities, oil & gas plants, and industrial facilities worldwide
“The turbine doesn’t care about your maintenance schedule. It only cares about what you actually did.”
Issue 01 — Clogged Air Inlet Filters: The Silent Efficiency Killer
Turbine breathes. Thousands of cubic meters of air per hour. And when that air has to fight its way through a blocked filter, the engine is already losing the battle before fuel even enters the picture. Output drops. Fuel consumption creeps up. Compressor blades start collecting grime.
The tricky part? It happens slowly enough that technicians often miss it until a performance review flags the numbers. By then, compressor fouling has set in — and now you’re dealing with two problems instead of one.
Issue 02 — Compressor Fouling: The Performance Drain Nobody Talks About
Even perfect inlet filters don’t catch everything. Fine particles still slip through and slowly coat the compressor blades. Aerodynamics get disrupted. The compressor works harder, the compression ratio falls, and fuel efficiency takes a hit. Over time, it’s not just fouling — it’s erosion and corrosion.
Water washing helps, but doing it wrong — wrong chemicals, wrong timing, wrong intervals — can cause thermal shock or accelerate corrosion. The wash itself becomes the problem.
Issue 03 — Lube Oil Degradation: The Hidden Threat to Bearings
Here’s the uncomfortable truth: lube oil looks fine long after it’s stopped doing its job. It oxidises quietly. It picks up metal particles. It turns acidic. And bearings running on degraded oil don’t fail loudly — they fail slowly, expensively, and at the worst possible time.
Changing oil on a fixed schedule without testing it is guesswork. The only reliable approach is regular oil sampling and analysis — knowing the actual condition of what’s inside the machine.
Issue 04 — Actuator & Control Valve Failures: When Precision Goes Wrong
Gas turbines operate within very tight parameters. Fuel-air ratios, speed, load — all managed by actuators and EHC (Electro-Hydraulic Control) valves. When these components wear or fail, the turbine doesn’t just run less efficiently. It trips, or worse, it runs outside safe limits without anyone realizing.
The early signs are subtle: a slightly sluggish load response, a minor fluctuation in speed. By the time it’s obvious, you’re already in reactive mode.
Issue 05 — Exhaust Back-Pressure: The Problem at the Wrong End
Most maintenance attention goes to the front and middle of a gas turbine. The exhaust end gets overlooked — until blocked flue gas filters start increasing back-pressure across the system. The turbine has to push harder to exhaust gases, temperatures rise in the hot gas path, and efficiency drops across the board.
In industrial and high-particulate environments, exhaust filters can degrade faster than expected. It’s not exciting maintenance. But neglecting it is quietly expensive.
“Proactive maintenance isn’t a cost. Unplanned downtime is.”
None of these issues are mysteries. They’re well-understood, predictable, and — with the right program in place — entirely manageable. The difference between a turbine that runs reliably and one that becomes a maintenance nightmare usually comes down to how early problems are caught, and how well the team is equipped to handle them. That’s exactly what ATTS Inc. has been helping operators do for over two and a half decades.
Frequently Asked Questions
How do I know when to replace gas turbine air inlet filters?
Differential pressure across the filter housing is your best signal — more reliable than visual checks or fixed time intervals. In harsh or coastal environments, inspection frequency may need to increase significantly compared to clean-air sites.
What’s the difference between online and offline compressor washing?
Online washing is done while the turbine is running and helps maintain performance between planned outages. Offline washing is done at standstill and is more thorough — it removes heavier deposits that online washing can’t reach. A good maintenance program uses both strategically.
How often should lube oil be tested in a gas turbine?
Gas turbine lube oil is usually tested monthly for running turbines and quarterly for standby turbines. The schedule should be changed if test results show contamination, oil degradation, or abnormal wear.
What are early warning signs of actuator or EHC valve wear?
Watch for slow or inconsistent response to load and speed controls, minor hydraulic fluid seepage near the actuator, or unexpected trip events without a clear cause. These are the subtle signals that get ignored until they become an emergency.
Why does exhaust back-pressure affect turbine performance?
When the exhaust path is restricted — usually by blocked flue gas filters — the turbine has to work harder to expel gases. This raises temperatures in the hot gas path, increases fuel consumption, and puts additional stress on components. It’s one of the most overlooked efficiency drains.
Need support for your turbine maintenance program?
ATTS Inc. supplies precision turbine parts, specialty chemicals, filtration systems, and on-site maintenance services — globally, for over 27 years.
Email: sales@atts-inc.com Phone: +1-856-810-0006
Website: atts-inc.com