The cost of repair depends on the specific problem, the condition of the unit, and which components need attention. A single failed thermostat, heating element, valve, or control is usually a more limited repair than a problem involving several parts or damage that affects the tank itself.
Maintenance costs are generally more predictable because the work focuses on preventive service rather than correcting an active failure. The final price can vary depending on the type of water heater and the work required, such as inspecting accessible components, checking valves and connections, looking for leaks or corrosion, and flushing a storage tank when needed.