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You are in Phoenix. We also have a Tucson site.

You are in Phoenix. We also have a Tucson site.

Why Is My Water Heater Leaking?

Did you know that the average U.S. household leaks around 10,000 gallons of water every year? While ten percent of households waste more than 90 gallons per day in this way! With stats like that, we wish it was only our refrigerator running!

Many of these leaks happen due to simple issues like faulty fittings and faucets, but there's one culprit that homeowners dread: water heater leaks.

Water heaters seem like simple systems until you're trying to track down the source of a steady drip. With so many valves and pipes feeding into them, you may be wondering, "Why is my water heater leaking, and what do I do about it?"

We've got you covered. Let's take a look at some of the most common reasons for water heater leaks, which ones you can address on your own, and when you have to stop playing the hero and call an experienced plumber. 

Most Common Culprits for Leaks

Though we'll discuss them in more depth below, here are a few of the most common causes of water heater leaks. The reasons behind these leaks range from minor to major. 

Poor or Loose Connections

Connection issues are common culprits when it comes to leaks, and they happen for two main reasons.

First, a former technician may not have connected each part of your water heater as intended. The improper installation of copper water lines, for example, can require more accurate soldering.

Second, connections on your water heater that were once secure can begin to loosen over time. Water heaters undergo slight shifts and movements as they work, which can cause fittings or connections to loosen.

Faulty, Worn, or Broken Components

As your water tank ages, its components become more likely to wear down or break. This is more likely for certain parts than others: the anode rod, for example, takes a great deal of corrosion from the hot water tank.

High Pressure

Heating your home's water creates steam, and this steam turns your hot water tank into a pressurized environment. Your temperature pressure relief valve allows this steam to discharge, but it doesn't prevent all issues. If your tank's temperature is too high or if the water entering your tank is already at high pressure, it can create a leak from the strain.

Sediment Buildup

As water circulates through your water heater, minerals from the water may collect on the bottom of the tank. Homeowners who drain and flush their tanks clear away these deposits, but those who don't allow the deposits to grow. Over time, enough buildup can cause cracks and leaks.

Cracked or Corroded Tank

Water heaters require a double-shelled tank to work. The inner shell holds water, and the outer shell insulates that water. If either of these water tanks grows cracked or corroded, repairs are often impossible.


Prepare Your Heater

Before you start hunting down the source of your leak, take a few steps to prepare your heater and ensure your safety.

First, turn off the unit's power. For many units, you can start by finding the temperature dial on the bottom of the tank and turning it off.

For a gas water heater, find your gas shut-off valve, which is often near the top. For an electric water heater, you'll want to head to your breaker box and turn off the breaker that powers your heater. If you can't find these components, be sure to check your owner's manual.

Next, shut off the unit's water. Find the shutoff valves, which sit toward the top of most water heaters. You should see one for hot water and one for cold, turn both of them off.

It's also a good idea to shut off your home's main water supply line. This can help keep the rest of your home plumbing safe as you work on your water heater.

Grab your set of wrenches if you have one, along with some spare paper towels. Depending on where your water heater sits, you may want to grab a stepladder to inspect the top of it with care.


Rule Out Other Causes

It's easy to jump to the worst-case scenario when you think your heater is leaking, but make sure you've ruled out other causes first.

If your HVAC system runs through the same room as your water heater, check for leaks there first. Simple tactics like changing your filter or checking for a clogged condensate drain line can help you troubleshoot your HVAC leak.

Next, rule out condensation. This phenomenon is most likely to happen when your water heater is in a cold room. As condensation builds, it may drip in a way that convinces you the system is leaking.

Wipe down your water heater with a towel and let it sit for a while. If you return to find that an even film of moisture has formed across its surface, you're looking at condensation, not a leak.


Locate the Source of Your Leak

If you've ruled out other causes, it's time to find the source of your leak. It can often be hard to tell where water is coming from at a slow drip, and leaks from the top of your water heater can even trickle down and make it look like the water is coming from elsewhere.

That's why we recommend starting your search at the top of your unit and grabbing a spare paper towel to help.

Run your paper towel over the pipes above the water heater to see if it comes back damp. If so, you may have an issue with the pipes or fittings.

Next, run a paper towel around the valves and fittings around the bottom and sides of your tank. Wherever your paper towel comes back damp is the most likely culprit for your leak.


Leaking Water Supply Lines

If you find that your leak is coming from the top of your water heater, your water supply lines are often to blame.

Check the hot and cold water inlets, which bring water into your system. A loose connection here easily can cause leaks that drip across your unit. Grab your wrench and tighten the fittings to see if that stops your leak.


Leaking T&P Valve

Your temperature and pressure relief valve, also called the T&P valve, helps to relieve the high pressure inside your tank. If this valve is faulty or loose, the pressure inside the tank can build, causing a leak to spring up.

If the water seems to be dripping from your T&P valve, lower the pressure in the tank.

Start by tightening the fitting around this valve: if you're lucky, that will be enough to do the trick. If the valve itself is damaged or faulty, however, you'll need to replace it. In the meantime, keep the tank's pressure low.


High Pressure or Temperature

Aside from T&P valve issues, water pressure can build in your tank for other reasons. If your gas or electric water heater temperature is set too high, it can create excess steam. This, in turn, can cause too much pressure to build.

Check the temperature of your tank. The U.S. Department of Energy recommends setting your water heater thermostat to around 120ºF. This can slow pipe corrosion and mineral buildup within your tank, and it can also save you money on your energy bills.


Leaking Drain Valve

The most common reason for leaks from the bottom of a water heater is the drain valve.

As part of their regular maintenance checklist, homeowners should drain and flush their water heaters to remove mineral deposits. If you're lucky, the problem may be that you forgot to close the drain valve all the way. You should also check for a loose fit and ensure that the valve is snug in place by twisting it clockwise.

Alternatively, the leak may be the result of a corroded or faulty valve. Though you can drain your tank and replace the valve on your own, an experienced plumber is often a safer bet for handling this job.


Too Much Sediment

If your water heater accumulates enough sediment, the buildup can affect its performance over time.

Odd noises, cooler water, cloudy or rusty water, and decreased hot water pressure in your home are all red flags before you even see a leak. You might also notice rising gas or electric bills, depending on the type of water heater you own.

Often, a sediment build-up may cause your tank to leak water from the drain valve or elsewhere toward the bottom of your tank, even though the root cause doesn't lie with the tank's other components. These kinds of leaks are often fatal to a heater, as cracks and rust within the tank itself lower its performance and ability to function properly.


Corroded Anode Rod

Your unit's anode rod attracts corrosive components within your water heater's system, keeping these components from damaging the unit itself. Over time, however, this corrosion can wear down the anode rod. In some cases, this component may wear away so much that it almost disappears.

Hot water heater leaks due to anode rod issues are often easy to fix. A simple part replacement will do the trick.


Damaged Shell

If you're having a hard time tracking down the source of your leak, a damaged internal or external tank may be to blame. A layer of metal covers both shells, but it's still possible for issues to crop up under this protection.

Damage to the external shell is often a bit easier to spot, as you may notice corrosion or discoloration. More often than not, however, external tank damage turns into a rupture and flood, so you're likely to notice it!

Damage in your water heater's internal shell, on the other hand, can be more subtle. Check the area where your tank sits in its enclosure. If you find water leaking in this area, you might be looking at structural issues.

Problems with a water heater's shells can be hard to fix, and often require a full replacement.


Old Tank

Last, but not least, leaks become more common as your water heater ages. Over time, each part of your water heater begins to wear down. Exposure to corrosion, high pressure, and sediment buildup can speed up the wear and tear.

If you've been noticing warning signs of aging from your leaky water heater, it might be time to consider a replacement. Here are some common signs that your water heater is going out:

  • Strange noises

  • Strange smells from your water

  • Discolored water

  • Lower hot water pressure

  • Cooler water temperatures

  • Higher energy bills

  • Frequent hot water shortages

Check the age of your water heater by looking for its installation date, which is often located on a label somewhere on the unit. Keep in mind that the average water heater should last anywhere from six to thirteen years, though some newer models can last longer.


When to Repair vs. Replace Your Unit

If you're looking at serious issues, how do you know when to repair or replace your unit?

Water heater repair is often a safer bet for newer units as well as models you've maintained well. If you do a good job of flushing the tank, checking connections regularly, and getting a professional check-up every once in a while, you're more likely to only need a simple repair.

Water heater replacement, on the other hand, is what we recommend for models that are around eight to ten years old. We also recommend a replacement if you've noticed any of the red flags we've mentioned above for aging water heaters, such as discolored water or higher energy bills.


Why Is My Water Heater Leaking?

Staring at your unit, perplexed and asking, "Why is my water heater leaking?" can be quite stressful. But remember, you're not in this alone!

Parker & Sons is here to serve as your trusted companion in these challenging moments. With our seasoned expertise in plumbing services, we're ready to swoop in and tackle those baffling leaks dampening your spirits. What's more, we pride ourselves on our swift response time – because we believe you shouldn't have to wait days to regain your comfort.

Why struggle with the mystery when the solution is a call away? Get in touch with us today, ask your questions, or better yet, schedule a visit. At Parker & Sons, we're not just about fixing problems; we're about restoring peace in your home.  

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