Tankless water heaters typically last 20 years or more with proper maintenance — nearly twice the lifespan of a traditional tank water heater. However, in Illinois’s hard water environment, annual descaling maintenance is critical to achieving that full lifespan. Without it, mineral buildup can reduce efficiency and cause premature failure within 10–12 years.
Service Life Depends on Water and Maintenance
Tankless equipment can provide a long service life, but the result depends on correct sizing, installation, water quality, venting, and maintenance. Mineral scale insulates the heat exchanger and can reduce flow or efficiency. Units serving hard water generally need more attention than equipment supplied with properly treated water.
Maintenance That Protects the Heat Exchanger
- Follow the manufacturer’s descaling interval and approved procedure.
- Clean inlet screens and serviceable filters.
- Keep intake and exhaust terminations clear.
- Check for stored fault codes, unusual noise, or temperature fluctuation.
- Have gas pressure, combustion, condensate drainage, and safety controls evaluated as applicable.
Annual service is a common starting point, but the correct interval depends on water hardness, usage, and manufacturer requirements. A licensed professional can explain whether treatment or isolation valves would make future maintenance easier.
Repair or Replace?
Repair may be sensible when the heat exchanger is sound and the needed component is available. Replacement becomes more likely when leaks involve the heat exchanger, repair parts are obsolete, capacity no longer matches the home, or repeated failures make ownership unpredictable. Compare the full installed scope, not only the appliance price: venting, gas supply, condensate disposal, electrical requirements, permits, and water treatment can affect the project.
Schedule Plumbing Service
For an inspection and clear repair options, visit our related Wheaton plumbing service page or call 630-733-9000.