Why Tankless Water Heaters Need Annual Flushing in Hard Water Areas

Tankless water heaters are renowned for their energy efficiency and compact footprint. However, many homeowners in Bergen and Essex County do not realize that tankless units require periodic maintenance—specifically, flushing mineral scale from the heat exchanger.

Understanding Mineral Scale in North Jersey Water

Water supplies across northern New Jersey contain varying levels of dissolved minerals like calcium and magnesium. When hard water is rapidly heated inside a tankless unit’s copper or stainless steel heat exchanger, these minerals calcify and form a hard scale layer on the internal walls.

Symptoms of Scale Buildup in Your Tankless Unit

• Error Codes: Modern units like Navien, Rinnai, and Noritz display error codes indicating flame failure or overheating when scale blocks heat transfer.
• Fluctuating Water Temperatures: Cold water sandwich effect or sudden drops in hot water pressure.
• Increased Energy Bills: Scale acts as an insulator, forcing the unit to burn significantly more gas to achieve the desired water temperature.

How Professional Descaling Works

Flushing a tankless unit involves connecting a circulation pump to isolation valves with food-grade white vinegar or specialized descaling solution. The pump circulates the solution for 45 to 60 minutes to dissolve mineral buildup without harming internal components.