6 Signs Of Water Heater Failure

What’s happening to my hot water?

Running water from a faucet over a sink
Photo: Fabian Schmidt / EyeEm / Getty Images
Running water from a faucet over a sink
Photo: Fabian Schmidt / EyeEm / Getty Images
Xiao Faria daCunha
Contributing Writer
Updated September 13, 2024

Highlights

  • Signs of water heater failure include insufficient or inconsistent hot water, leaking water heater, unusual noises, low pressure, and discoloration.

  • Sediment buildup is one of the key culprits behind a failing water heater.

  • Traditional water heaters can last from 6 to 15 years. Tankless water heaters can last from 15 to 20 years.

  • The cost to replace a water heater is $882 to $1,802.

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Nothing kills the mood more than freezing water in the middle of a steaming shower. Plus, the harm of a failing water heater goes beyond inconvenience. Therefore, you should always look for the signs of a water heater failure to stay proactive. As with all appliances, the sooner you address abnormalities, the better.

Why a Failing Water Heater Is Dangerous

While water heaters often feel like background appliances, they are one of the major pieces keeping your home running. If your water heater fails, it can lead to real dangers beyond the discomfort of not having hot water on demand. 

The main threats of a failing water heater include:

  • Water damage: A failing water heater may begin to leak or even burst, causing severe water damage to the floors below, surrounding areas, and personal items. If left unaddressed, the water damage may lead to mold growth or significant structural damage.

  • Electrical hazards: Gas and electrical water heaters both have electric components. Faulty parts, circuits, or connections to the main power supply can cause shock and bodily injuries.

  • Overheating: A malfunctioning thermostat may lead to overheated water that’s too hot to be safe for skin exposure. If overheated water pours out of a showerhead, you can end up in serious burns.

Signs of Failing Water Heaters

Thankfully, a failing water heater gives plenty of warning signs. If you know what you’re looking for, you can take action and either repair or replace your water heater in time.

1. Insufficient Hot Water

The most obvious sign of water heater failure is a lack of hot water supply. If you can’t get enough hot water in the shower or while using the sink, your water heater might be going out. A tanked water heater usually stores enough hot water for several household members to take a full shower. Meanwhile, a tankless water heater should never run out of hot water.

If your water heater has a tank, it can collect sediment buildup over time. This slowly chips away the storage space available for hot water, reducing your water heater’s capacity. Sediment buildup can also result in clogged or corroded pipes, leading to more severe damage. Therefore, performing regular maintenance and flushing your tank annually is crucial.

If you have a tankless water heater, insufficient hot water usually suggests a mechanical or electrical issue that a licensed professional should address.

2. Leaking Water Heater

Look for pooling water under the water heater and check for surface moisture. These are both signs of potential leaks. Leaking water heaters can cause water damage to floors and even lead to mold growth, so they should be addressed as soon as possible.

Water heater leakage can come from multiple sources. Check all valves and connections to ensure they are properly connected and sealed. Next, check any pipes to ensure they’re not cracked and leaking. However, if you notice a leak in the water tank, it’s best to have a professional handle it.

3. Unusual Noises

Your water heater should never make any unusual noises beyond normal vibration from it turning on and off. If you hear banging, gurgling, or clanging noises, something is definitely not right. Loud noises from the water heater deserve your immediate attention. Based on the sound, you might be able to guess what’s wrong. However, it’s the safest to have a professional to check it out. If possible, refrain from running hot water until the problem is diagnosed and repaired.

4. Inconsistent Temperature

If you get splashes of lukewarm or cold water during a hot water run, something might be wrong with your water heater’s heating element, such as the fuse. Sometimes the thermostat might malfunction, stopping your water heater from heating the water to the desired temperature. To replace a faulty unit, expect to spend $50 and $250. However, you might need a pro to help identify the exact problem.

5. Low Water Pressure

Decreased water pressure is another sign of failing water heaters. This can be caused by a leaking or faulty pressure valve, a leaking tank, issues with the connecting pipes, or sediment buildup. Annually flushing your water heater will prevent buildup from affecting the water pressure. However, if the problem is caused by a failing temperature and pressure relief (TPR) valve, bring a licensed pro to repair the issue immediately. A faulty TPR valve can cause your water heater to explode.

6. Discoloration and Odors

If you only notice discoloration and strange smell when running hot water, something might be going on with your water heater. This is usually caused by mineral deposits and other sediment buildups. Some of these deposits may be harmful to your body or irritate your skin. Others might clog the hot water lines over time, leading to bigger plumbing problems.

How to Know You Need to Hire a Pro for a Failing Water Heater

Generally speaking, it’s best to have a licensed water heater repair professional work on your water heater. It is a complicated appliance that requires electrical and plumbing knowledge most homeowners do not have. Plus, working with hot water can be dangerous for the inexperienced.

Can I DIY Water Heater Repairs?

Generally, you should not attempt DIY water heater repairs if you think the appliance is failing. If the problem with your water heater is caused by a loose connection, you can easily tighten things up yourself. Otherwise, anything mechanical, electrical, and plumbing-related should be handled by a licensed and insured professional.

How to Prevent Water Heater Failures

All appliances age and fail, but there are ways to extend your water heater’s life span and prevent major problems. Understanding the signs of water heater failure is critical to prevention. If something sounds or feels unusual, trust your gut feeling and have someone inspect the water heater.

Water heaters need to be flushed at least once a year. Some may recommend a flush every six months or so if you have high usage. You should also adjust the temperature seasonally and set your water heater to vacation mode if you are away for a few days. Proper insulation will also help keep your water heater up and running.

How Much Does It Cost to Repair or Replace a Water Heater?

A water heater repair contractor usually charges by the hour, plus the cost of parts. On average, water heater repair costs range between $90 and $1,730. However, your final cost might be higher if you need plumbing and water damage restoration services. Therefore, it’s always best to have someone inspect your water heater as soon as you notice one of the above signs of water heater failure.

The cost to replace a water heater is $882 to $1,802 on average. A new traditional tanked water heater costs from $2,500 to $3,000. Traditional water heaters last from 6 to 15 years. A new tankless water heater costs $2,614 on average but can last 15 to 20 years. A third option is hybrid water heaters, also known as heat pump water heaters. These are the most expensive options and can cost $6,000 to $9,000 without installation.

Frequently Asked Questions

Old age and lack of maintenance are the two main reasons why water heaters fail. Older units tend to run harder, while different parts become more prone to malfunctions. Meanwhile, not maintaining your water heater properly, such as not flushing the tank regularly, can cause sediment buildup and put extra distress on the unit. You should also conduct an annual inspection to ensure your water heater runs properly.

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Learn more about our contributor
Xiao Faria daCunha
Contributing Writer
Xiao is a full-time writer giving advice and tips on improving living spaces so it functions as a peaceful sanctuary and an efficient factory. She is visual artist with substantial woodshop experience and isn’t afraid to pick up a circular saw. She is also a volunteer builder for Kansas City’s Habitat of Humanity.
Xiao is a full-time writer giving advice and tips on improving living spaces so it functions as a peaceful sanctuary and an efficient factory. She is visual artist with substantial woodshop experience and isn’t afraid to pick up a circular saw. She is also a volunteer builder for Kansas City’s Habitat of Humanity.
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