Causes of Knocking or Similar Noises in Your West Jordan Water Heater

There are a few situations in our homes where noises coming from various components are giving us some strong signals about what’s going on, and a good example here is your water heater. In particular, have you begun to hear knocking, rumbling or related sounds as if something is banging on the interior walls of your water heater? This is a common issue, it turns out.

At My Buddy the Plumber, we’re happy to provide numerous water heater services, including water heater repair, water heater replacement and more, to clients in West Jordan and other parts of the greater SLC area. What is the most likely cause of this sort of knocking sound taking place in your water heater, and what needs to be done about it? Here’s a simple rundown.

Primary Cause of Knocking or Rumbling Sound

While it’s technically possible for other issues to be at play here, these are rare situations. Rather, by far the most common cause of this knocking sound in your water heater is simple: Sediment has begun to build up on the bottom of your water heater tank.

This is a problem that generally comes about due to having hard water, as the mineral deposits from hard water will gradually settle on the bottom of your tank over time. As this sediment buildup gets thicker and more widespread, it will begin to impede heat transfer in your tank. In response to this, your water heater will begin to heat the water more aggressively to make up for the lost efficiency, and this is what leads to the knocking or rumbling sound you’re hearing.

This is due to the simple reality of how the gas burner works within your water heater. The heated water boils and bubbles while being heated below the sediment layer — but once it finally bursts through, a booming sound results.

If you’re having trouble visualizing this, just imagine a covered pot on a hot stove that’s heating up water inside. Eventually, the water is going to become hot enough that it will bubble up and eventually burst out through the lid. The same principle is at play in your water heater.

Problems With Water Heater Sediment Buildup

There are a few different problems that can come from sediment buildup in your water heater, and the most direct one is simply that it will lead to increased energy usage as your water heater tries to make up for the efficiency loss. This means higher energy bills each month, as well as a shorter lifespan for your water heater overall.

Sediment buildup can also cause other serious issues. For example, if too much sediment builds up and becomes compacted, it can actually cause your water heater tank to crack. While this is a rare problem, it’s one that needs to be taken seriously — especially since a cracked water heater tank can lead to serious flooding in your home.

Draining the Water Heater Tank

Luckily, the vast majority of these situations come with a simple solution: Flushing the water heater tank to remove this sediment and return it to like-new operations.

Before we go over how to do this, a quick note: We’re going to approach this mini-tutorial as if you’re the one performing this task. However, if you feel even the slightest bit uncomfortable with any part of this process, or if you simply want to ensure the very best results, please don’t hesitate to reach out to our team of plumbers at My Buddy the Plumber. We would be more than happy to come out and take care of this problem for you, flushing your water heater tank and returning it to top condition — and we can also take a look at your entire plumbing system while we’re there. Do not feel obligated to attempt this job if you aren’t totally comfortable.

That said, let’s look at the simple steps for flushing a water heater:

• Turn it off: First and foremost, it’s very important to make sure that your water heater is completely off before attempting any sort of maintenance or repairs. If you have a gas water heater, simply turn the knob to the “pilot” position; if you have an electric water heater, flip the breaker switch for your water heater off at your electrical panel.
• Turn the cold water off: Locate the cold water inlet valve for your water heater (it will be on the pipes leading into the tank), and turn it to the “off” position.
• Connect a hose: Find an available garden hose, and connect one end to the drain valve at the bottom of your water heater tank. Run the other end of the hose outside, placing it in an area where any water that comes out won’t cause any damage or problems.
• Open the drain valve: Return to your water heater, and slowly open the drain valve. You may need to use a wrench to do this, as these valves can sometimes be quite tight. Allow the water to begin draining out of your tank; once it has, open the pressure relief valve (usually located just above the drain valve) to help speed up the process.
• Allow the water to drain: Let the water continue draining until it runs completely clear. This process can take anywhere from a few minutes to half an hour, depending on how much sediment has built up in your tank.
• Close the valves: Once the water is running clear, close both the drain valve and pressure relief valve, and turn the cold water inlet valve back on.
• Turn on the power: Finally, turn your gas water heater back to the “on” position, or flip the breaker switch for your electric water heater back on at your electrical panel.
• Test the water heater: Allow a few minutes for the tank to fill back up with water, then turn on a hot water tap in your home and allow it to run for a minute or two. This will help clear any remaining sediment out of the line, and ensure that your water heater is once again operational.

For more on how to remedy a water heater experiencing knocking or rumbling noises, or to learn about any of our West Jordan plumbing or HVAC services, speak to our team at My Buddy the Plumber today.