Tankless Water Heater Maintenance: 4 Easy Tips to Prolong Lifespan

Tankless water heaters are efficient, space-saving, and long-lasting—but only if they’re correctly maintained. In Central Texas, where hard water is a common issue, regular maintenance is crucial to keep your system functioning optimally. At CMM Plumbing, we’re certified by Navien and Rinnai and proudly help homeowners in Coupland, Austin, and nearby cities extend the life of their tankless water heaters.

Why Maintenance Matters for Tankless Water Heaters

Unlike traditional water heaters, tankless systems heat water on demand. While this improves energy efficiency, it also means that components are more sensitive to mineral buildup, especially in areas with hard water, such as Central Texas. Without regular maintenance, issues like reduced flow rate, poor heating performance, and costly breakdowns can occur. Regular care not only protects your investment but keeps your system running like new.

1. Perform an Annual Flush to Remove Mineral Buildup.

Hard water minerals, such as calcium and magnesium, can accumulate inside your unit, especially in areas like Coupland and Round Rock. This buildup can reduce efficiency and cause long-term damage.

• How to Flush: Use a descaling solution or vinegar, following your manufacturer's instructions, or hire a professional for a thorough flush.
• When to Flush: At least once per year—or more often if you notice performance issues.

Why Flushing Matters If minerals build up inside the heat exchanger, it can cause overheating, reduce hot water flow, and even trigger error codes. Flushing also prevents the scale from hardening inside the unit, which is much harder to clean and may require replacement parts. Regular flushing helps keep energy usage low and extends the efficiency of your unit.

2. Clean or Replace the Inlet Filter and Screens:

Your tankless unit has a small filter that catches sediment before it enters the system. If it becomes clogged, your water pressure and heating efficiency can drop.

• DIY Tip: Turn off the water supply, remove the filter, and rinse with clean water.
• Pro Tip: Let CMM Plumbing inspect and replace filters during annual service.

Where to Find Filters Filters are usually located in the cold water inlet. Some units also have additional screen filters or pre-filters. Make sure they are checked during every maintenance session.

Why Filters Matter? Even small particles, such as rust or sand, can wear out internal parts if not caught early. Clean filters help maintain water quality and flow rate, reducing strain on the heat exchanger and sensors inside the unit.

3. Check for Leaks or Corrosion Around the Unit.

Inspect your unit for any signs of rust, moisture, or leaks. These could be early warnings of more serious issues.

• What to Look For: Dripping connections, rust-colored stains, or musty odors.
• When to Act: Immediately—leaks can lead to water damage and shorten your heater’s lifespan.

Preventing Corrosion Leaks often starts at fittings or in the heat exchanger. Early detection can prevent expensive repairs or even the need for full unit replacements. Adding a water softener can also reduce corrosion caused by mineral buildup. If you have existing corrosion, don’t ignore it—call a licensed plumber to assess and address the issue.

4. Schedule Professional Maintenance Annually

Routine professional checkups keep your warranty intact and help catch minor problems before they become expensive.

• What We Do: At CMM Plumbing, we perform descaling, inspect components, clean filters, and run diagnostics to ensure everything runs smoothly.
• Bonus: Ask about our maintenance plan to make yearly tune-ups easy and affordable.

What a Maintenance Visit Includes

• Descale flush
• Filter cleaning
• Gas pressure and vent checks
• Inspection of water and gas line fittings
• Full system diagnostics

How Long Does It Take? Most maintenance visits last 1 to 2 hours and can help prevent years of wear and tear on your unit.

Bonus Tip: Consider a Pre-Filter or Water Softener System. To reduce the frequency of maintenance and extend your system's life, consider installing a water softener or pre-filter system. These devices help minimize the minerals that cause scale, making maintenance easier and your system more efficient.

Common Myths About Tankless Water Heater Maintenance

"I don’t need maintenance because it’s new." Even new systems can suffer from mineral buildup quickly in areas with hard water.

"Flushing once every few years is fine." Not in Texas. Hard water demands at least annual service.

"DIY maintenance is always enough." While you can handle some tasks, only a professional can adequately inspect and diagnose issues before they escalate and become more severe.

Final Thoughts & Call to Action:

Tankless water heaters offer numerous benefits, but like any appliance, they require regular maintenance. With just a few maintenance tasks each year—and support from a trusted local plumber—you can protect your investment and enjoy reliable hot water for decades.

Are you ready to schedule your annual tankless water heater tune-up? Contact CMM Plumbing at cmmplumbing.com/contact or call (737) 233-1822.