The cost to service a tankless water heater is $600 on average, but it can cost between $75 and $1,300, depending on the type and scope of the repair.
The cost of maintaining your tankless hot water heater can range from as little as $75 and up to $1,300 for more extensive repairs. On average, the cost to service tankless water heaters is $600. A water heater is an essential part of every home, but you may not appreciate it until it suddenly stops working. Your tankless water heater might be out of commission due to the pilot light going out or a complex leak to the heat exchanger. But maintenance can help keep your water heater running efficiently and extend the life of the unit.
The size of the tankless hot water heater may impact the cost of repairs and maintenance. As with most maintenance, the cost varies depending on what issues the plumber finds when inspecting your tankless hot water heater and the components connected to it, such as water, gas, or electrical lines. From there, it’s all about how much parts cost and how long it takes for the plumber to fix any components.
Maintenance costs vary depending on the parts that need to be replaced and the type of fuel the water heater uses, such as electricity, gas, or solar. Repairs can also depend on the brand of tankless water heater you have.
| Water Heater Part | What It Does | Average Cost (Part Only) |
|---|---|---|
| Fuse | Safety feature cuts electricity when water gets too hot | $20 |
| Thermostat | Controls water temperature | $200 |
| Heating element | Heats the water | $10 |
A water heater repair pro costs between $45 and $200 per hour, depending on your location, job complexity, experience level, and other factors. If a professional completes their inspection or repair within 30 minutes, they will most likely bill you for the entire hour.
The cost to do maintenance and repairs on a tankless water heater differs based on labor costs. To get an estimate for your specific issue, find a water heater repair expert near you. Here’s a breakdown of the estimated costs in different U.S. cities.
| City | Cost Range |
|---|---|
| Austin, TX | $200–$1,000 |
| Charlotte NC | $180–$900 |
| Chicago, IL | $220–$900 |
| Cleveland, OH | $200–$850 |
| Boise, ID | $150–$500 |
| Boulder, CO | $290–$1,400 |
| Denver CO | $250–$1,100 |
| Indianapolis IN | $240–$1,050 |
| Los Angeles, CA | $230–$1,100 |
| Moab, UT | $300–$1,000 |
| Portland, ME | $140–$600 |
| Portland OR | $270–$1,100 |
| San Francisco, CA | $240–$1,100 |
| Seattle, WA | $400–$1,400 |
| Sedona, AZ | $200–$1,000 |
| Wilmington, NC | $200–$800 |
Beyond the cost of a plumber, the price tag of maintaining or repairing your tankless water heater primarily depends on what’s broken and what needs to be replaced. Here’s an estimated cost breakdown based on the issue.
Repair costs are part of any maintenance program. By using an appliance like a tankless water heater, natural wear and tear occurs and the worn-out parts need to be replaced. As you might expect, repair costs depend on the parts being repaired or replaced. Here are some of the more common repairs for tankless hot water heaters.
| Repair | Average Cost Including Labor |
|---|---|
| Fuse | $50–$75 |
| Pilot light | $75–$150 |
| Pipes | $100–$350 |
| Pressure relief valve | $75–$150 |
| Thermostat | $75–$150 |
| Vent | $50–$125 |
Several issues can cause your tankless water heater to go on the fritz, making it important to know which maintenance steps need to be taken to restore your water heater to working order. Here are some of the most common tankless water heater problems that could need repairing.
Electric tankless water heaters could trip your breaker, and if your heater isn’t working, your fuse might be damaged. In general, these are more straightforward repairs, and a replacement fuse costs around $20.
A gas water heater has a pilot light that could go out for various reasons. Although you may need a replacement part, the bulk of the cost to fix this issue is labor. Service calls by a plumber usually range from $45 to $200 per hour.
While you can diagnose a pilot light issue yourself, be sure that you feel comfortable handling gas before attempting to make the repair. If you work on the repair yourself and smell a gas odor, be sure to call a professional right away.
It costs approximately $100 to $300 to replace a thermostat on a tankless water heater. You can save labor costs by replacing the thermostat yourself, but remember to turn off the breaker before you begin.
As a rule of thumb, leaks should almost always be handled by a professional. Your water heater leak could be due to a bad seal, sediment buildup, compromised pipes, or faulty valves. Depending on the severity of the leak, costs could be up to $1,000.
A professional plumber should also address pipe problems, which range from leaks to cracks, corrosion, and holes. These may require patches or other part replacements. Pipe repairs cost from $100 to $350, depending on the location and complexity of the repair needed.
Repair costs for pressure relief valves range from $75 to $150. Pressure relief valves serve the important function of relieving the pressure buildup resulting from the expansion of heating water. Whether it needs to be replaced or repaired, it’s highly important to keep this part working properly. Common pressure relief valve problems include becoming loose, cracked, or damaged somehow. This is another job for a professional plumber, not a DIY fix.
You can also break down the cost of your maintenance repairs by the type of part that needs replacing. Below are three common replacements for tankless water heaters.
Heating elements are the more dangerous components of a water heater because they receive high voltages of electricity. In general, a professional will charge $200 to $300 to repair a heating element and it’s often worth the cost to avoid personal injury. But you can test your heating elements with a continuity tester before calling a pro, which costs about $10 at the hardware store.
A new pressure relief valve costs about $20, but your total costs could go up to $200 if you hire a professional to install it. It can be worth having a professional come out to see whether the valve needs fixing or if it's just a sediment buildup. If you replace the valve yourself, be sure to turn off your gas first.
The gas valve in your tankless water heater works with other components to maintain the water temperature and activation of the pilot light. Aside from playing an important role in the essential function of your water heater, the gas valve is also a safety feature by shutting off the gas flowing to the pilot light if the unit doesn’t light. You can expect water heater gas valve replacement to cost about $350 on average.
Sometimes, your tankless water heater doesn’t need repairs. Instead, it needs services to clean it out and fix the underlying issue. Here’s what you need to know about the cost of tankless water heater services.
Even though your hot water heater doesn't have a storage tank, it still should be flushed to remove sediment. If your water heater is making noise, it’s a sign that your heater may need to be flushed. By clearing out residue, your water heater will last longer and run more efficiently. A flush service by a plumber costs approximately $200. You can flush the unit yourself, but follow the recommended steps to avoid damaging the pump.
Mineral deposits from your water build up over time as the water heater cycles water through the system. Scaling is when the mineral deposits and limescale build up inside the pipes and other parts of the hot water heater.
If you live in an area with hard water, especially using well water, scaling occurs much more quickly and requires more frequent maintenance. It can also be the reason why your water heater isn’t draining properly. Flushing and descaling are important parts of that maintenance, no matter what kind of water you have. Descaling your tankless water costs between $150 and $450 on average.
Depending on the fuel type your hot water heater uses, the unit will have different parts, which will cause maintenance costs to vary across types. Different parts wear differently from design to design and may vary in complexity and time required to work on them. Here are the average maintenance costs by fuel type:
| Fuel Type | Average Cost Including Labor |
|---|---|
| Electric | $100–$600 |
| Gas | $150–$650 |
| Oil | $150–$650 |
| Propane | $150–$650 |
| Solar | $200–$700 |
The cost to repair your tankless water heater by yourself depends on which part needs to be fixed. You’ll need to cover replacement parts along with basic tools like a screwdriver and wrench if you don’t already have them. Repairing the water heater yourself saves you the cost of a plumber or water heater specialist, which ranges from $45 and $200 per hour. Consider handling basic fixes on your own, but more complex repairs are best handled by a professional to reduce the risk of personal injury and further damage to your tankless unit.
If you have an electric water heater, turn off the electricity to your unit before testing or repairing, as a high voltage of electricity runs through these units. If you have a natural gas or propane water heater, turn off the gas or propane before working. If the repairs needed are extensive, you may want to compare repairs to water heater replacement costs.
Scheduling routine preventative maintenance on a hot water heater is the easiest and most effective way to save money on tankless hot water heater maintenance costs.
If you do need to call a water heater pro for repairs outside of scheduled maintenance, try to call during regular business hours to avoid paying a premium.
Pay for parts and pick them up or have them shipped to the site. This can save you money that the plumber would charge you for the legwork involved in getting parts.
If you find that your water heater needs more maintenance than it should or that it can’t keep up with hot water production, you may want to consider what size tankless water heater you need. Replacement cost may be more up front, but it may reduce the number of repairs needed and solve the problem of not having enough hot water.
If your water heater is beyond repair, no amount of financial investment will be worth fixing the problem. Instead, consider replacing your water heater entirely with a new unit—especially if your tankless water heater is approaching the 20-year mark or you notice other signs you need a new water heater. You can replace your tankless water heater with another unit, a high-efficiency tank water heater, or a hybrid water heater.
If you’re on the fence as to whether a tankless water heater is worth it or not, a hybrid water heater may be a good option, as it uses functions from both conventional tank water heaters and tankless water heaters to efficiently heat water in your home.
Repairing a tankless water heater yourself can save you money on hiring a pro, but many water heater repairs require significant plumbing and electrical expertise. Some homeowners can conduct simple repairs themselves, like replacing a fuse, but anything beyond a very basic repair is best left to the pros, otherwise, you run the risk of further damaging your unit and creating safety hazards. Improper repairs can also potentially void your water heater’s warranty.
So when in doubt, hire a local water heater repair pro who can ensure the repair is done safely and efficiently without voiding your warranty.
Before committing to a water heater pro, ask them the following questions to find the right professional for the job.
Are you licensed and insured to work on this project?
What’s your experience with my brand and model of water heater?
Do you offer workmanship guarantees?
Can you provide references from previous clients?
How do you handle unforeseen challenges and charges?
What steps do you take to ensure safety during the repair?
How will you dispose of old parts?
Are there any potential additional costs I should be aware of?
How long do you expect the repair to take?
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Tankless water heaters don’t require much maintenance. Most only need an annual flush if you live in an area with hard water or periodic servicing when you see an error code. A flush helps keep sediment from building up and allows your water heater to work more efficiently.
If you’re preparing to winterize your home, flush your unit and use the bleed valve to pump air out before blowing water out of your pipes. You can also call a pro to handle this for you.
Your tankless water heater should be serviced every few years. If you live in an area with hard water, then an annual flush is recommended. Always watch for error codes and noises to see whether you need to service your tankless heater sooner. Find a water heater repair pro to inspect and service your water heater if you suspect any issues.
Without maintenance, a tankless water heater may need to be replaced far sooner than one that is maintained regularly with preventative maintenance to the valves, pipes, thermostat, heat exchanger, and other components. With regular maintenance, a tankless water heater will last up to 20 years, often with a warranty of 12 to 15 years.
