How Much Does it Cost to Repair a Tankless Water Heater?

Jenna Jonaitis
Written by Jenna Jonaitis
Updated January 24, 2022
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The typical cost to repair a tankless water heater falls between $220 and $956 with the average cost being $587

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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 off or a complex leak to the heat exchanger. The average cost to repair a tankless water heater is $587, with the typical range being $220 to $956. Simple fixes can cost as little as $100, while more extensive ones can cost up to $1,300

In some cases, the price to repair your hot water heater exceeds what it would cost to get a new one. Tankless water heaters can last up to 20 years or more, so if your heater is almost a couple of decades old, it could be time for a replacement.

How Much Does It Cost to Repair a Tankless Water Heater Near You?

The cost to repair 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 repair costs in different U.S. cities.

CityCost Range
Chicago, IL$215-$897
Boise, ID$134-$496
Portland, ME$153-$629
Wilmington, NC$186-$708
Boulder, CO$271-$1,320
Seattle, WA$387-$1,392
Austin, TX$198-$982
Moab, UT$305-$1,014
Sedona, AZ$286-$977
San Francisco, CA$233-$1,116

How Much Does It Cost to Repair Your Tankless Water Heater Yourself?

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, which usually ranges from $45 and $150 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.

Tankless Water Heater Repair Cost Breakdown

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Beyond the cost of a plumber, the price tag of 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 reason for repair.

Blown Fuse or Tripped Breaker

Electric tankless water heaters could trip your breaker. Your fuse also might be damaged if your heater isn’t working. In general, these are more straightforward repairs, with a replacement fuse costing around $20.

Pilot Light Issue

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 $150 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.

Broken Thermostat

It costs approximately $100 to $300 to replace a thermostat on a tankless water heater. You can save labor costs by replacing the thermostat on your own, 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. Costs could be up to $1,000, depending on the severity of the leak.

Heating Element Replacement

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.

Pressure Relief Valve Replacement

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.

Water Heater Flush

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.

Labor Costs

A plumber costs between $45 and $150 per hour, depending on your location. If a plumber completes their inspection or repair within 30 minutes, they will most likely bill you for the entire hour.

FAQs about Tankless Water Heaters

Do tankless water heaters require maintenance?

Tankless water heaters don’t require a lot of maintenance. Most tankless water heaters 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 or cottage, be sure to flush your unit and use the bleed valve to pump air out before blowing water out of your pipes. You can also call a professional to handle this for you. Learn about the pros and cons of tankless water heaters to decide if one is right for your home.

How often should a tankless water heater be serviced?

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 local water heater repair person to inspect and service your water heater if you suspect any issues.

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