Where To Install Water Hammer Arrestor

Where to Install a Water Hammer Arrestor: A Comprehensive Guide

Water hammer, that unsettling banging sound in your pipes, is a common plumbing problem. It's caused by the sudden stop of water flow, creating pressure surges that can damage pipes and fittings over time. The solution? A water hammer arrestor. But knowing where to install it is crucial for effective protection. This article provides a comprehensive guide on water hammer arrestor placement for optimal results.

Understanding Water Hammer and its Causes

Before diving into placement, understanding the root cause of water hammer is essential. It typically occurs when:

• Appliances rapidly shut off: Dishwashers, washing machines, and even toilets create sudden water flow stops.
• Valves close quickly: A fast-closing valve, such as a ball valve, can trigger water hammer.
• High water pressure: Excessive water pressure exacerbates the impact of sudden flow cessation.
• Long pipe runs: Longer pipes amplify the effect of pressure waves.

Strategic Placement of Water Hammer Arrestors

The key to effective water hammer prevention is strategic arrestor placement. Here's a breakdown of optimal locations:

1. Near the Source of the Problem:

This is the most effective strategy. Install the arrestor immediately upstream of the appliance or valve causing the hammer. For instance:

• Washing machine: Install the arrestor on the cold and hot water supply lines before they connect to the washing machine.
• Dishwasher: Similar to the washing machine, place it on both supply lines before they reach the dishwasher.
• Toilet: Install the arrestor on the supply line before it connects to the toilet fill valve.

2. On Individual Appliances or Fixtures:

If you're experiencing water hammer from multiple sources, installing arrestors on each problematic appliance is the most comprehensive approach. This offers targeted protection and prevents the issue from spreading.

3. On Long Horizontal or Vertical Pipe Runs:

For long stretches of pipe where water hammer is prevalent, installing an arrestor at the end of the run can significantly reduce the impact. This is particularly useful in areas with significant pressure fluctuations.

4. Consider using Multiple Arrestors:

In extensive plumbing systems or buildings with multiple water-using appliances, employing multiple arrestors is often necessary for complete protection. This distributed approach provides comprehensive protection against water hammer across the system.

Choosing the Right Water Hammer Arrestor:

Selecting the appropriate arrestor size and type is crucial. The size should match the pipe diameter of the supply line. Consider these factors:

• Pipe size: Ensure the arrestor's connection size matches the pipe diameter.
• Flow rate: A higher flow rate may require a larger arrestor.
• Material: Copper, brass, or plastic arrestors are commonly available.

Avoiding Common Mistakes:

• Installing it too far from the source: The closer the arrestor is to the source of the water hammer, the more effective it will be.
• Ignoring multiple sources: If you have water hammer in multiple locations, address each source individually.
• Incorrect sizing: Using an improperly sized arrestor may not adequately absorb the pressure surge.

Conclusion:

Successfully mitigating water hammer requires careful planning and correct arrestor placement. By understanding the causes of water hammer and strategically installing arrestors near the problem sources or along long pipe runs, you can significantly reduce, or even eliminate, those irritating bangs and protect your plumbing system. Remember to choose the right size arrestor and consider using multiple units for comprehensive protection.