range of tankless water heaters

Water Heater Repair: Things to Consider

Table of Contents

So many things around your home require hot water, from your washing machine and dishwasher to your own showers and baths. Because it's likely out of sight, your water heater is likely also out of mind. In fact, most people only think of this essential appliance when it doesn't function properly and needs water heater repair. Before you start troubleshooting a hot water heater repair, however, consider common issues and seek professional help if you don't feel comfortable doing it yourself.

Before You Begin

Sometimes, water heater repair requires only something simple, such as dead batteries in a leak detection alarm. Before you get started, do these two things to save time and aggravation: attempting to fix it yourself or calling someone for water heater repair service.


Check the Fuses/Breaker in Your Home

If the only symptom of your problem is no hot water, the water heater repair you need may just be changing a fuse or flipping the breaker. Keep in mind, however, that this type of malfunction often indicates a more serious problem. Barring power surges tripping the breaker or blowing the fuse, this problem may mean you need hot water repair for your thermostat or upper heating element.

Check the Warranty

Losing access to hot water may ruin your day, but the bright side is that your warranty may cover water heater repair service. Many manufacturers cover replacement parts and repairs in some cases, so check the paperwork that came with your unit. Some, including A. O. Smith, have web pages dedicated to verifying your warranty.

Common Water Heater Problems

Though water heaters are complex appliances, there are several common causes professionals look to first during troubleshooting. The most common problems with water heaters include the following.

Water Isn't Hot Enough

Several problems cause your water to not heat up enough, with the easiest being one or both elements are set too low. Also, your water heater may not be big enough for your space, or you may have a leak in your home's pipe system. If the problem only occurs on single showerheads or faucets, you may have a faulty thermostatic mixing valve. When it's none of these things, check for a bad lower heating element or thermostat. 

No Hot Water at All

When your faucets deliver no hot water at all, it's typically due to two main reasons. First, your home's electrical wiring systems and circuit breakers may have issues. Sometimes, overloads in one area can cause downstream effects. If this isn't the problem, you may have a burned-out upper heating element.

Water Temperature Is Too Hot

If your water temperature is too hot, you may have your thermostat set too high. Though you can adjust the temperature yourself, it's probably best to find a service provider who can perform water heater repair service on your unit.

Hot Water Runs Out Too Fast

Installing a unit that can't handle a home your size is the most common cause of this problem. If you run out of hot water frequently, use our water heater selector tool to find a unit more aligned with your needs. This tool considers flow rates based on your model, hot water use per occupant, how much hot water each uses at the same time, and your bath and shower sizes.

Rust-Colored Water or Bad Odor

The presence of a non-toxic sulfate reducing bacteria, Divibrio Sulfurcans, can cause rust-colored water and water that has a bad odor. This bacterium creates the energy it needs to survive by converting sulfate(SO4) to hydrogen sulfide(H2S) gas you smell in the water. 

The simplest treatment available is the shock-chlorination of the system. This is a surface treatment, and often requires repeated trials in heavily infected systems. The chlorination of a system requires that you follow each step explicitly to avoid an untreated portion of the piping system from reinfecting another part and needs to be done by a professional.

Tank Is Hot to the Touch

An issue with a hot-to-the-touch water heater may be a malfunctioning thermostat, but it's best not to take chances. The T&P valve is blocked, professionals will be required. Remove if you don't know what you are doing.

Water Leaks

Loose fittings and connections are the most common causes of water leaks. A faulty pressure relief valve, however, may be the culprit, as can be a corroded or cracked tank.

Tank Making Noises

Popping noises in your hot water tank usually mean you have sediment in your water heater, while pressure in the system may cause a banging noise called a "water hammer," which requires professional help. Whistling noises may indicate a blocked valve, and hissing usually means you have sediment inside the tank. Sediment buildup at the bottom of the tank also causes vibrating noises.

Low Water Pressure

Many times, faulty pressure regulator valves cause low water pressure. When this issue is caused by your water heater, however, it's typically due to a blocked or damaged hot water shutoff valve.

Status Light Flashing (Gas)

When the status light on your gas water heater flashes, it usually indicates a lack of power to the unit or an empty tank. Other issues include problems with your thermostat or a pilot light that's gone out.

Should I Repair or Replace My Hot Water Heater?

turning the cold water off

Hot water heaters provide comfort and convenience that we often take for granted until things go wrong. Like other mechanical systems in your home, these appliances incur damage from daily wear and tear, causing many common malfunctions that require your attention. Let’s explore the pros and cons of replacing vs. water heater repair to help you decide what’s best for your water heater.

Repair Pros & Cons

The main advantages of water heater repair are that it typically costs less than replacing your entire unit, and it takes less time out of your life. The downside, however, is that, unless it's a minor issue, the problem is likely to persist, requiring more water heater repairs going forward while only adding a short time to its life span.

Replacement Pros & Cons

The benefits of replacing your water heater depend on its age and the necessary repairs. For instance, older units may be out of warranty, while new units come with one, usually paying for the water heater repair cost.

Likewise, newer units are typically more energy efficient, potentially saving you money on power use. The upfront cost plus the time required, however, are disadvantages of replacement.

When Is Replacement Necessary?

When your water heater is 10 to 15 years old and keeps having issues, replacement may be necessary. To decide what's best, compare the hot water repair cost against the price of a new unit.

Should I Call a Plumber, or Can I DIY Fix My Water Heater?

Electric water heaters, tank and tankless

Though DIY electric, gas and tankless water heater repair is possible, it's usually less of a hassle to contact a plumber instead, especially if you're unsure of the issue. These professionals have all the tools and training they need to handle virtually any water heater repair, and many bring along common replacement parts to speed up the repair process.

Tools Required

The most common tools you need for water heater repair include:

  • Adjustable wrench
  • Pipe wrench
  • Pipe cutter
  • Plunger
  • Plumber's tape
  • Screwdriver
  • Drain pans and buckets
  • Multimeter
  • Joint compound
  • Plumber's putty
  • Torch igniters (for gas water heater repair)

When to Call a Pro

If you have limited plumbing experience, calling a pro is your best bet. Plumbers typically have experience and tools specific to the task that you probably don't, so they can fix the issue faster and more effectively.

Benefits of Hiring a Plumber for Fixing Water Heaters

water heaters pro

The main benefits of hiring a plumber for residential and commercial water heater repair or emergency water heater repair include the following.

Right Tools & Parts

Plumbers carry the right tools with them for most jobs, and many also stow extra parts on their trucks for faster repairs.

Safety & Experience

Years of experience doing water heater repair make plumbers your best bet. These professionals also have the right gear to keep them safe while working with electricity.

Guaranteed Work

When you hire a professional, they typically guarantee their work for a set period of time for added confidence.

Saving Time

Unless you have training in plumbing, hiring a professional almost always saves you time on water heater repair. Generally during one of these repairs, the water heater will be down for about a day.

Develop Relationship

When you find a plumber who understands your needs and quotes a reasonable water heater repair cost, develop a relationship so you can call them again if things go wrong.

Typical Water Heater Repairs and Maintenance Costs

mother and daughter using the sink

Replacing the Heating Element

Heating elements heat up the water in your unit, making them essential parts. Replacing the parts takes roughly 3 hours for those with basic electrical and plumbing skills, but set aside more time for the task because the tank must cool before you begin. The cost of the parts runs between $10 and $60.

Replacing the Dip Tube

The dip tube's primary function is routing cold water to the bottom of your tank, where it's heated. When this part goes out, replacement parts typically cost only around $10.

Replacing the Anode Rod

The anode rod attracts sediment in your water heater, taking on corrosion so your tank doesn't have to. When this part goes, your tank may start corroding instead, making replacement vital. An anode rod typically costs around $50, and a novice can usually replace it in around 15 minutes.

gas tankless water heater

Replacing the Tankless Heat Exchanger

A tankless heat exchanger draws cold water in and pushes hot water out of your tankless water heater. Though the part costs $400 to $800, this tankless water heater repair is necessary because your unit doesn't work without it. In most cases, seeking professional help for this replacement is a good idea.

Installing a Thermal Expansion Tank

Thermal expansion tanks capture heated water as it expands in your water heater to reduce pressure and increase safety. Though this part wasn't essential in the past, many states have begun requiring their installation on closed-loop water heater systems. Due to the potential damage to pipes and your water heater, professional installation is recommended.

Tank Cleaning & Flushing

Flushing and cleaning your water heater tank removes the sediment built up inside it, helping the unit operate faster and better. Fortunately, this is a relatively simple task for most homeowners to perform in roughly 2 hours.

When you need water heater repair, use this list to decide if doing it yourself is worth the hassle. 

Replacing the Thermostat (Lower and Upper)

Your water heater's lower and upper thermostats control how water passing through the unit heats up, so replacing these parts means more consistent, reliable heating. Each one typically takes 2 to 3 hours to install, depending on your skill level. Thermostats for electric water heater repair cost roughly $20, but some parts for gas water heater repair cost more due to their complexity.

Replacing the Pressure Relieving Valve

The pressure relief valve ensures your water heater operates at safe pressure levels, and it's vital to the functioning of your unit. The part itself costs around $15, and replacement is simple for DIYers with basic skills, taking around 15 minutes.

gas tankless water heater

Replacing the Recirculating Pump

A recirculating pump ensures your water heater provides hot water on demand, so it's vital to operation. Unfortunately, costs for the part run anywhere from $400 to $3,200, and this water heater repair is complex, so professionals need to complete the job.

Replacing the Flue Pipe

Water heater flue pipes vent harmful gasses out of your water heater and home, making them essential for safe appliance operation. Though these parts cost between $10 and $30, depending on your unit, they typically require professional installation due to the difficulty level and the need for permits in some areas.

Replacing the Timer

Water heater timers let homeowners time when they want the appliance to operate, and they're usually an energy-efficient addition to homes that run on a regular schedule or homes that are unoccupied for a few months out of the year. The good news is this optional part costs roughly $60, but the good news is that it's a relatively easy part for novices to install in just a couple of hours.

gas tankless water heater

Checking the Water Pressure

Checking the water pressure keeps the pressure from getting too high and damaging your water heater and other appliances. Fortunately, this task is easy to do and requires just a few minutes of your time and a pressure gauge, which typically costs between $10 and $20. 

Corrosion Protection

The two most common ways your water heater corrodes are through thermal expansion and high water pressure. Replacing your anode rod regularly is a simple DIY repair that costs about $50 and takes only 15 minutes, but if your water is corrosive, you may need to call a professional for water softener installation. This can cost anywhere from $200 to $6,000, depending on the size and quality of the system.

Gas Heater Repairs and Maintenance

pilot light

Replacing the Gas Control Valve

The gas control valve opens and closes to let in or keep out gas from the line that powers your water heater. A defective gas control valve is considered an emergency water heater repair, so call a professional immediately. Replacing this part usually costs between $300 and $500, and it's not a DIY job for most people.

Replacing the Igniter

Igniters on gas water heaters are push-button systems that light the gas entering the system to power your unit. If this part is defective, call a professional for replacement. Costs for this gas water heater repair run between $75 and $350.

Cleaning the Flame Arrestor

Flame arrestors prevent explosions by stopping flames from entering closed systems with combustible gasses. Though these parts last a while, they do need regular maintenance and cleaning. Fortunately, this task is a simple one you can perform by vacuuming the flame arrestor or cleaning it with a stiff wire brush to remove all debris.

Performing a Draft Test

Adequate air combustion is a must for a gas water heater, and performing a draft test ensures your space has ample air for safe operation. Though you can perform this test yourself, fixing the issue means calling a professional and costs between $100 and $500.

When you need gas water heater repair, use this list to see whether you should call a service provider or do it yourself. Keep in mind that many of these repairs require a firm understanding of gas appliances, so call a professional if you have any doubt about your skill.

Replacing the Thermocouple/Thermopile

This component of gas water heaters lets you know when the pilot light goes out, and a faulty part means you can't relight your pilot light. Fixing this issue typically costs around $200 when you call a pro or $20 for the part if you do it yourself.

Relighting the Pilot Light

The pilot light on your gas water heater ignites gas entering the system to power your unit. Though you can relight it yourself, you must follow all safety precautions outlined in your water heater manual. If you don't feel confident, calling a plumber to relight your pilot light usually costs between $40 and $150.

gas tankless water heater

Benefits of Regular Water Heater Maintenance

Water heaters do so much around our homes that we rarely think about, and taking care of them on a regular schedule ensures they continue to perform up to our expectations. Keep these appliances in good working order by following all manufacturer maintenance recommendations. 

Let’s look at how regular water heater maintenance benefits you in key ways.

Optimum Performance and Efficiency

Water heaters that are well maintained typically perform at peak efficiency to save you money on energy costs. This means ridding your unit of sediment buildup and preventing potential corrosion by flushing the tanks as needed as well as checking and cleaning the heating elements. While performing maintenance, visually inspect the overall unit to ensure there are no issues.

Increase the Life of Your Water Heater

Water heaters are an expensive investment, so maintaining your existing unit extends its lifespan. The way sediment and minerals accumulate in your system has the potential to damage key parts and reduce its efficiency. Routine maintenance enables smooth operation and monetary savings over the long term.

Peace of Mind & Protection

Peace of mind is worth more than gold, and knowing you’re protected helps you sleep better each night. 

When you know your water heater is well-maintained, you can feel confident in taking a hot shower before work, running your dishwasher as you leave and knowing you can wash a load of clothes when you return. 

A proactive approach also protects your family should issues with a gas water heater create a potentially dangerous situation.