Steam traps are essential components in steam and thermal fluid systems, responsible for removing condensate and non-condensable gases while preventing the loss of live steam. When functioning correctly, they maintain energy efficiency, protect equipment from damage, and ensure consistent system performance. However, like any mechanical component, steam traps can fail — and when they do, the consequences can include increased energy consumption, water hammer, corrosion, and even total system failure.
At ISIS Fluid, we supply and support reliable steam system solutions across industrial sectors. In this article, we highlight five of the most common steam trap failures and explain how to prevent them before they escalate into costly issues.
Applications and Benefits of Bimetallic and Thermodynamic Steam Traps
VALSTEAM ADCA UBS20 | BIMETALLIC STEAM TRAP UNIVERSAL STEAM TRAPS & CONNECTORS
VALSTEAM ADCA UDT46 | THERMODYNAMIC STEAM TRAP UNIVERSAL STEAM TRAPS & CONNECTORS
The VALSTEAM ADCA UBS20 Bimetallic Steam Trap is ideal for removing condensate and air in steam systems, ensuring efficient heat transfer. Its stainless steel, maintenance-free design makes it durable and easy to install, though it performs best in steady load conditions.
The VALSTEAM ADCA UDT46 Thermodynamic Steam Trap is perfect for high-pressure systems and steam tracing applications. Compact and energy-efficient, it offers reliable condensate removal but is less suited to low-pressure or light-load systems.
1. Dirt and Blockages
One of the most common causes of steam trap failure is the accumulation of dirt, rust, scale, or debris within the trap or upstream piping. Over time, these particles can obstruct the trap’s internal mechanisms or clog the built-in strainer, leading to performance issues. A blocked trap may prevent condensate from draining properly, resulting in waterlogging and poor heat transfer. In some cases, particles may damage internal sealing surfaces, causing the trap to leak steam continuously.
Prevention Tips: To prevent this failure, it’s essential to install strainers upstream of each trap to capture contaminants before they reach sensitive components. Regular cleaning of the strainer and inspection of drain lines should be integrated into routine maintenance schedules. Using high-quality piping and ensuring the steam system is flushed and treated before commissioning can also minimise debris build-up from the outset.
2. Incorrect Sizing or Installation
Steam traps must be correctly sized for the system’s pressure, condensate load, and flow rate. An oversized trap may cycle too frequently, increasing mechanical wear, while an undersized one might struggle to discharge condensate, leading to pooling or water hammer. Incorrect installation — such as poor orientation, back-pressure issues, or inadequate drainage slope — can also compromise the trap’s function, causing inefficiency and early failure.
Prevention Tips: Choose traps based on specific application parameters, including maximum and minimum load conditions. It’s also important to adhere strictly to manufacturer installation guidelines, ensuring proper positioning, pitch, and orientation relative to the condensate line. Pipework layout should support effective drainage and avoid the creation of pockets where condensate can accumulate.
3. Mechanical Wear and Tear
Over time, continuous exposure to high pressures, temperatures, and cycling causes internal parts of steam traps — such as valves, floats, seats, and thermostatic elements — to wear down. This wear can result in the trap becoming stuck in an open or closed position. If stuck open, it wastes steam and energy; if closed, it traps condensate, reducing heat transfer and potentially damaging downstream equipment.
Prevention Tips: Invest in high-quality steam traps suited to the specific demands of the system. Establishing a preventive maintenance programme — with scheduled inspections and part replacements — will help catch signs of wear early. Using diagnostic tools such as ultrasonic detectors or thermal imaging can assist in identifying malfunctioning traps without shutting down the system.
4. Water Hammer
Water hammer is a severe form of hydraulic shock that occurs when condensate accumulates and is suddenly pushed by steam, creating a high-velocity surge. This can damage trap internals, pipework, and valves. Steam traps exposed to water hammer can fail abruptly due to cracked housings or misaligned components.
Prevention Tips: To avoid water hammer, ensure that condensate is removed promptly and that the steam system is designed to avoid rapid pressure changes. Use appropriate pipe gradients and avoid sudden directional changes in the layout. Installing pressure-reducing valves and silencers, or employing traps designed to withstand hydraulic shock, can also protect the system.
5. Condensate Contamination
In some systems, poor water treatment or leaks in heat exchangers can cause the condensate to become acidic or chemically aggressive. This contaminated condensate corrodes the internal components of steam traps, leading to early failure, leaks, or even structural damage to the valve body. Corrosion may also create particles that contribute to further blockages downstream.
Prevention Tips: Proper water treatment, including deaeration and pH balancing, is essential for long-term steam trap performance. Regular testing of condensate samples will help identify contamination early. Where contamination risk is high, using steam traps made from corrosion-resistant materials such as stainless steel can significantly extend service life.
Building a Reliable Steam System
Avoiding steam trap failure isn’t just about fixing what breaks — it’s about building systems designed for resilience and reliability. At ISIS Fluid, we encourage clients to adopt a comprehensive approach to steam trap management. This includes maintaining a full inventory of installed traps, scheduling periodic audits, and using modern diagnostic tools to assess performance in real-time.
Training staff in steam system operation and steam trap maintenance is also vital. When on-site teams understand how steam traps work and what failure signs to look for, issues can be identified and resolved more quickly — preventing larger problems from developing.
Explore Our Range of Steam Traps
Choosing the right steam trap is essential for keeping your system running safely and efficiently. At ISIS Fluid Control, we offer a comprehensive range of high-performance steam traps designed to suit a variety of applications, from industrial steam systems to sensitive pharmaceutical processes. Our products are engineered to deliver reliable condensate removal, minimise energy loss, and extend the life of your equipment.