Why is My Water Heater Making a Banging Noise

Are you hearing an eerie, banging noise from your water heater while it’s running? While it may sound like someone trapped in your gas tank is trying to get out, it’s not as grim as that. What you hear is a common water heater phenomenon that’s either a minor issue or a serious cause for concern.

Nevertheless, such an uncanny sound calls for your closer attention as it’s likely worth scheduling your local plumber for a more thorough inspection. Let’s break down where that banging noise really comes from.

Sediment Build-up

The most common culprit to this plumbing distress is mineral build-up within your water tank or tankless water heater. This issue can be more frequent and recurring if you’re in an area with hard water (when an unhealthy amount of minerals contaminates your tap).

But while the sound may appear ghostly, you don’t need some prayers to turn it away. You can regularly flush your water tank at least once or twice a year or descale your tankless water heater. This prevents the excess mineral deposits from reacting with the heating element, which usually causes those mini explosions or popping noise.

Mineral build-ups harm both regular and tankless water heaters, which leads to several other problems in the long run. With regular cleaning maintenance, you can thwart sudden heater meltdowns or a hefty water heater repair.

Issue with the Pressure Relief Valve

In some instances, the banging noise you hear is simply caused by water pressure within your tank. You can expect a sudden increase in pressure when your thermostat kicks in to heat the water reserve. 

The unmistakable hint to this issue is that the banging sound occurs once you start the water heating process and subsides once the reserve is flowing. You can blame this on a faulty pressure relief valve failing to hold up its task. You can personally inspect and reconfigure the valve to its right setting if it’s improperly adjusted or have it replaced if it’s already broken. Always maintain the ideal pressure of 40 to 80 psi to get rid of this pressure-driven banging.

Thermal Expansion

Water’s many physical properties include its expansion when heated. You’ll eventually hear that thudding sound when there’s no extra room within your tank to accommodate such expansion.

Think of it as a water pressure problem. When your relief valve is stuck, it prevents the excess pressure from escaping, leading to the same noise. But, to address this, you’ll need a thermal expansion tank rather than a relief valve. It’s a specialized tank made precisely to absorb the expanded water volume, preventing pressure buildup that can potentially damage your tank and valve.

If you haven’t got one, that banging noise may be your hint for an expansion tank installation. If your existing expansion tank is no longer up to par, a repair or replacement is more suitable.

Water Hammer

Does that banging noise sound like someone’s hammering your tank? It’s most likely what experts refer to as a water hammer, a fitting name for its nature. This is when the water traveling through your plumbing comes to a sudden halt, creating a shockwave that causes pipes to vibrate against other structures, like your water tank.

Water hammer may stem from abruptly shutting the valve, high water pressure, loose pipes, or lack of air chambers in your plumbing. Though not urgent, this issue also needs a timely plumbing service to avoid damaging your pipes and address potential loose connections in your system.

Getting That Banging Distress? King Rooter & Plumbing Got You Covered

Is your water heater giving you that sinister vibe from that constant banging sound? Forget about exorcism; what you need is a trusted plumber who can get to the bottom of your compromised water heater.

For everything water heater-related, only trust King Rooter & Plumbing for dependable solutions. We offer comprehensive water heater services like installation, repair, and maintenance. From banging sounds to emergency repairs, you can trust our plumber to be there delivering the much-needed TLC to your unit.

So, don’t wait for that banging to rule your cozy showers. Let the plumbing king restore your water heater’s peace.