You’re standing in your basement or utility room, and suddenly you hear it: popping, rumbling, knocking, maybe even a little whistling.
Your water heater is making noises. And it’s not just talking to itself.
In most cases, your water heater is trying to tell you something important. And the sooner you listen, the better. Let’s walk through what those noises mean, what’s likely causing them, and how to fix the problem before you’re left without hot water.
The Most Common Cause: Sediment Buildup
If your water heater is popping or rumbling, you’ve probably got sediment at the bottom of the tank.
In cities like Tiffin, we have some pretty hard water. This means the water is packed with minerals, mainly calcium and magnesium. Over time, these minerals settle at the bottom of your water heater tank and form a thick layer of sediment.
At first, this isn’t a huge issue. But as the sediment builds up, it starts to cause bigger problems.
What’s That Noise, Exactly?
That popping or rumbling sound you hear? That’s the water underneath the sediment trying to boil.
Imagine this: You put a brick on top of your stove burner, then set a pan of water on top of that brick and turn the heat on. How long do you think it will take for that water to heat up? It’ll probably take a while, and it’ll make a lot of noise while it’s trying.
That’s basically what’s happening in your water heater. The heating element is working overtime to push heat through that thick layer of sediment, causing steam bubbles to rise and pop, creating that rumbling or knocking sound.
The longer it goes on, the harder your water heater has to work and the shorter its lifespan becomes.
Other Reasons a Water Heater Might Make Noise
While sediment buildup is the most common culprit, it’s not the only reason your water heater could be making noise. Other potential causes include:
- Compromised inner lining
- Loose heating elements (in electric water heaters)
- Water pressure fluctuations
- Expanding and contracting metal inside the tank
- A failing valve or partially closed water shut-off valve
That’s why it’s always a good idea to have a licensed plumber inspect your system if your water heater starts making new or louder-than-usual noises, especially if it’s more than 7–10 years old.
Why You Shouldn’t Ignore the Sound
Here’s the deal: Water heater noise might not mean it’s about to fail tomorrow, but it does mean your system is under stress, and it’s only going to get worse.
Ignoring the noise can lead to:
- Higher energy bills (your water heater is working harder)
- Longer waits for hot water
- Premature wear and tear on the tank
- Leaks from pressure buildup
- A complete breakdown at the worst possible time
We’ve seen many water heaters in the Iowa City area go from “just making a little noise” to “flooded basement” in under a year.
How to Fix It: Flushing Your Water Heater
In many cases, the fix is straightforward, just flush the tank to remove the sediment buildup.
That’s why we recommend professional water heater maintenance once a year. During a maintenance visit, our team will:
- Flush the tank to remove sediment
- Check the anode rod (to prevent rust and corrosion)
- Test the pressure valve for safety
- Inspect for early signs of wear or leaks
- Ensure your unit is running safely and efficiently
The sooner you address the sediment issue, the easier and cheaper it is to fix.
Need Help With a Noisy Water Heater in the Iowa City Area?
If your water heater is making strange noises, we can:
- Inspect your unit to pinpoint the issue
- Flush out sediment buildup
- Give you honest advice on whether to repair or replace
- Keep your hot water running without the surprises
We proudly serve Iowa City, Coralville, North Liberty, Tiffin, Williamsburg, and surrounding areas.
Don’t Wait Until the Noise Turns Into a Leak
If your water heater is making noise, that’s your warning sign. Call us today or schedule service online, and we’ll help you stay ahead of the problem before it turns into a costly mess.
Call Ackerman Plumbing or request service now. Your hot water (and peace of mind) depend on it.