How Often Should You Flush a Tankless Water Heater? Once a Year, Twice With Hard Water

Why Flushing Your Tankless Water Heater Matters

Tankless water heaters heat water on demand rather than storing it. Minerals like calcium and magnesium accumulate inside the heat exchanger over time, restricting water flow, reducing efficiency, and potentially damaging your system.

So, How Often Should I Have My Tankless Water Heater Flushed?

At least once a year is the general recommendation. However, homes with hard water—or those experiencing reduced water flow—should consider flushing every six months. Hard water contains more minerals that settle in tankless systems faster than expected.

Signs It’s Time for a Flush

• Reduced hot water flow
• Fluctuating water temperature
• Strange noises from the unit
• Higher energy bills without obvious reasons

What Happens During a Tankless Water Heater Flush?

1. Turn off the unit and disconnect power and water supply
2. Attach hoses to the service ports
3. Circulate a descaling solution (vinegar or professional cleaner) for approximately 45 minutes
4. Rinse thoroughly before reconnecting water lines

Professional vs. DIY Flushing

While homeowners can attempt flushing themselves, professional service is typically recommended. Professionals not only flush the system but also check for leaks, test components, and verify proper operation.

How Flushing Protects Your Investment

Tankless water heaters can last 15 to 20 years with proper maintenance. Regular flushing reduces wear and tear, prevents clogs, and maintains efficiency, potentially extending your system’s lifespan significantly.