How Often Should You Flush a Tankless Water Heater? Once a Year, Twice With Hard Water
Flush a tankless water heater once a year, or every six months if you have hard water. Minerals build up inside the heat exchanger and choke its flow, and a few signs tell you a flush is due.
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?
- Turn off the unit and disconnect power and water supply
- Attach hoses to the service ports
- Circulate a descaling solution (vinegar or professional cleaner) for approximately 45 minutes
- 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.
Tankless Unit Due for a Flush?
A Clog Heroes technician flushes it, checks for leaks and gives you a written price before any work starts. Calls are answered 24/7 at (540) 518-2564.
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