Why Tankless Water Heaters Fail Early in Middle Tennessee Homes

Tankless water heaters have a reputation for long life and efficiency. When properly maintained, that reputation is earned. But in Middle Tennessee, many systems fail years earlier than expected.

The cause is rarely the unit itself.

Hard Water Is the Primary Issue

Middle Tennessee has mineral-heavy water. Calcium and lime naturally build up inside tankless systems, especially in the heat exchanger.

Without routine flushing, this buildup restricts water flow and traps heat.

Efficiency Drops Before Failure Happens

Before a tankless unit fails outright, it often shows warning signs:

• Longer wait times for hot water

• Fluctuating temperatures

• Error codes or shutdowns

• Increased energy usage

These symptoms are often mistaken for “normal aging.”

Missed Maintenance Accelerates Wear

Tankless water heaters are not maintenance-free. Manufacturers recommend annual service to keep internal components clean and operating correctly.

Skipping service allows mineral buildup to harden and become more difficult to remove later.

Why Early Failure Gets Expensive

When buildup is left untreated:

• Heat exchangers overheat

• Internal sensors become inaccurate

• Warranty coverage may be affected

Repairs or replacements cost significantly more than routine maintenance.

Final Thought

Tankless water heaters don’t fail early because they’re unreliable. They fail early because they aren’t serviced. Regular flushing is the difference between a system that lasts and one that doesn’t.