How to Fix Noisy Pipes - Water Hammer

Overview

Water hammer is a loud banging noise in pipes caused by water stopping suddenly. This guide covers fixing the issue.

Step-by-Step Fix

1. Listen carefully around your home, especially when taps are turned off or appliances like washing machines finish filling, to pinpoint the exact location of the banging noise. Pay attention to which pipes or appliances seem to trigger the sound most often, as this will help you focus your efforts.
2. Inspect all accessible pipework, particularly those in basements, utility rooms, or under sinks, for any pipes that are not firmly attached to joists or walls. Use appropriate pipe clips or clamps, ensuring they are the correct size for your pipes, to securely fasten any loose sections and prevent them from vibrating.
3. Measure your mains water pressure using a pressure gauge, which can often be temporarily fitted to an outdoor tap or washing machine connection. If the pressure exceeds 4 bar (approximately 60 psi), consider installing a pressure reducing valve (PRV) on your main incoming water supply to lower the overall system pressure.
4. Locate the water inlet hoses for your washing machine and dishwasher, as these appliances are common culprits for sudden water stops. Screw a water hammer arrestor directly onto the appliance's water inlet valve, then reattach the appliance's hose to the arrestor, ensuring all connections are hand-tight and leak-free.
5. Turn off your main water supply at the stopcock and open all taps, starting with the highest in your home and working down to the lowest, to completely drain the system. Once all water has run out, close all taps before slowly reopening the main stopcock to allow the system to refill gradually, pushing out any trapped air as it fills.

Common Symptoms & Diagnostic Resolutions

Review the common error codes and operating symptoms below to quickly identify the root cause of the fault before ordering replacement parts.

Frequently Asked Questions