Plate Heat Exchanger Water Hammer: Causes, Damage & Prevention Guide – Senovis

Have you ever heard a loud “bang” from your plate heat exchanger just after the pump suddenly stops?

That sound is usually a sign of water hammer—a hydraulic shock that can seriously damage your equipment if left unchecked.

In this article, we’ll explain what water hammer is, why it happens, and how to protect your plate heat exchanger from unnecessary failures.

🎥 Watch the full technical explanation here:

Long Video:
https://www.youtube.com/watch?v=puIvZ_p0Kac

Short Video:
https://www.youtube.com/shorts/o9Mm9gQV8a8

What Is Water Hammer?

Water hammer occurs when the flow of liquid suddenly stops or changes direction.

This commonly happens when:

A pump shuts down unexpectedly
A valve closes too quickly
Reverse flow occurs in the pipeline

Because water has momentum, it cannot stop instantly. Instead, its kinetic energy becomes a high-pressure wave that travels rapidly through the piping system.

In many industrial systems, water hammer pressure can reach 5–10 times the normal operating pressure, creating severe stress on the entire system. Opening and closing valves gradually during startup and shutdown is a widely recommended way to reduce pressure surges and water hammer.

How Water Hammer Damages a Plate Heat Exchanger

A gasketed plate heat exchanger is designed for efficient heat transfer, but repeated pressure shocks can significantly shorten its service life.

Common damage includes:

Plate deformation
Gaskets pushed out of the gasket groove
External leakage
Uneven plate compression
Cracked welded joints
Increased maintenance costs

If your application relies on a Gasketed Plate Heat Exchanger, choosing the correct equipment and maintaining stable operating conditions can greatly reduce these risks.

👉 Explore our collection:

https://pheheat.com/collections/gasketed-plate-heat-exchanger

The Two Most Common Causes

1. No Slow-Closing Check Valve

Without a slow-closing check valve at the pump outlet, reverse flow can generate a powerful pressure surge immediately after pump shutdown.

2. Valves Closing Too Quickly

Fast valve closure is one of the leading causes of water hammer.

Extending the valve closing time allows pressure to dissipate gradually instead of creating a destructive shock wave.

How to Prevent Water Hammer

Fortunately, preventing water hammer is much easier than repairing damaged equipment.

Install a Slow-Closing Check Valve

A slow-closing check valve reduces reverse-flow impact and minimizes sudden pressure spikes.

Increase Valve Closing Time

Whenever possible, increase the valve closing time from approximately 1 second to around 10 seconds.

Install Air Release Valves

Air release valves installed at high points in the piping system help absorb pressure fluctuations and reduce hydraulic shock.

Inspect Gaskets Regularly

Damaged or aged gaskets are often the first components affected by water hammer.

Learn more about replacement Plate Heat Exchanger Gaskets:

https://pheheat.com/collections/phe-gaskets

Don’t Ignore Plate Damage

Repeated pressure surges may permanently deform heat exchanger plates.

Even if leakage is not immediately visible, deformed plates reduce heat transfer efficiency and increase gasket wear.

If replacement is necessary, explore our Plate Heat Exchanger Plates:

https://pheheat.com/collections/phe-plates

What About Brazed Plate Heat Exchangers?

Although this article focuses on gasketed units, Brazed Plate Heat Exchangers can also be affected by water hammer.

Excessive pressure surges may damage brazed joints or cause internal leakage.

Learn more about our brazed heat exchanger solutions:

https://pheheat.com/collections/brazed-plate-heat-exchanger

Watch the Complete Demonstration

Want to see what water hammer looks like in a real system?

📺 Full YouTube Video

⚡ YouTube Shorts

Conclusion

Water hammer is more than just a loud noise—it is a warning sign that your piping system is experiencing dangerous pressure surges.

By installing a slow-closing check valve, extending valve closing times, using air release valves, and maintaining your heat exchanger regularly, you can significantly reduce the risk of expensive repairs and unexpected downtime.

Whether you’re looking for plate heat exchanger plates, replacement gaskets, gasketed plate heat exchangers, or brazed plate heat exchangers, choosing the right components and following proper operating practices will help keep your system running safely and efficiently.