Most Tankless Water Heaters Need This Annual Cleaning—Few Homeowners Do It
AIThis post was created with the assistance of artificial intelligence (AI).

TL;DR

Most tankless water heaters need an annual cleaning to prevent mineral buildup that reduces efficiency and lifespan. Few homeowners follow this routine, risking costly repairs and reduced performance.

Most homeowners with tankless water heaters do not perform the essential annual cleaning required to maintain efficiency and extend the unit’s lifespan, according to plumbing experts. This neglect can lead to mineral buildup, reduced hot water output, and higher energy bills, posing a risk to the system’s longevity.Tankless water heaters, praised for their durability and continuous hot water supply, require regular descaling to prevent mineral deposits from accumulating inside the heat exchanger. Experts from Hughes Plumbing Services Inc. and Done Rite Services recommend flushing the units once a year, especially in areas with hard water, to maintain optimal performance. The process involves shutting off power or gas, draining the system, and circulating a descaling solution like vinegar through the heat exchanger using a pump and hoses. Failure to perform this maintenance can cause mineral scale buildup, restricting water flow and heat transfer, which reduces efficiency, increases energy costs, and may lead to unit failure. Despite these clear benefits, many homeowners do not follow through with this routine, risking costly repairs and shortened equipment lifespan.
At a glance
reportWhen: ongoing, with recommendations for annua…
The developmentExperts warn that neglecting annual cleaning of tankless water heaters can lead to decreased efficiency and potential failure, but many homeowners overlook this maintenance step.

Why Regular Cleaning Is Critical for Tankless Water Heaters

Neglecting annual descaling can significantly impair a tankless water heater’s efficiency and durability. Mineral buildup reduces hot water flow, increases energy consumption, and can cause costly breakdowns. Regular maintenance not only preserves performance but also complies with manufacturer warranties, saving homeowners money over time.
Chromex Tankless Water Heater Flush Kit with NSF Certified Liquid Descaling Solution and 1/6HP Extra Strength Pump

Chromex Tankless Water Heater Flush Kit with NSF Certified Liquid Descaling Solution and 1/6HP Extra Strength Pump

  • Complete Flush Kit: Includes pump, hoses, bucket, and descaler
  • Universal Compatibility: Works with most tankless water heater brands
  • Effective Scale Removal: Removes deposits to improve efficiency and lifespan

As an affiliate, we earn on qualifying purchases.

As an affiliate, we earn on qualifying purchases.

The Maintenance Gap in Tankless Water Heater Care

While tankless water heaters are designed for long-term use—often exceeding 20 years—they require routine maintenance to operate efficiently. Experts emphasize that mineral deposits from hard water are the primary cause of performance decline. Many homeowners are unaware or neglect this annual cleaning, despite manufacturer recommendations. Proper maintenance, including flushing with vinegar or descaling solutions, is essential to prevent internal damage and ensure warranty compliance. The practice has become a standard recommendation among professional plumbers, but adherence remains inconsistent, especially in regions with hard water or high hot water demand.

“Staying on top of cleaning and maintenance protects the efficiency of your water heater, extends its life, and reduces energy costs.”

— Brandon Hughes, owner of Hughes Plumbing Services Inc.

Chromex Tankless Water Heater Flush Kit with NSF Certified Concentrated Vinegar, Dilutes to 4 Gallons and 1/6HP Extra Strength Pump

Chromex Tankless Water Heater Flush Kit with NSF Certified Concentrated Vinegar, Dilutes to 4 Gallons and 1/6HP Extra Strength Pump

  • Complete Tankless Water Heater Flush Kit: Includes pump, hoses, bucket, vinegar, and tags
  • NSF Certified Vinegar Solution: Concentrated vinegar dilutes to 4 gallons
  • Extra Strength Pump: 1/6 HP for efficient cleaning

As an affiliate, we earn on qualifying purchases.

As an affiliate, we earn on qualifying purchases.

Extent of Homeowner Awareness and Compliance

It is not yet clear how many homeowners are aware of the need for annual cleaning or regularly perform it. Data on actual maintenance practices remains limited, and compliance rates vary widely across regions and household types.
Brolena 3-in-1 Metal Filter Removal Tool for Rinnai Tankless Water Heater

Brolena 3-in-1 Metal Filter Removal Tool for Rinnai Tankless Water Heater

  • Universal Compatibility: Fits all Rinnai water heater filters
  • 3-in-1 Multi-Use Design: Suitable for screwdrivers, wrenches, and hand grip
  • Protects Filter Caps: Removes filters without damage or slipping

As an affiliate, we earn on qualifying purchases.

As an affiliate, we earn on qualifying purchases.

Encouraging Better Maintenance Practices in Homeowners

Industry experts plan to increase awareness through homeowner education campaigns and more explicit manufacturer instructions. Future efforts may include automated reminders or simplified cleaning kits to improve compliance and prevent avoidable failures.
Sediment Gone™ Water Heater Sediment Removal Tool – Flushes, Cleans & Breaks Up Sediment Clogs in Electric or Gas Water Heaters – Easy DIY Water Heater Cleaning Tool

Sediment Gone™ Water Heater Sediment Removal Tool – Flushes, Cleans & Breaks Up Sediment Clogs in Electric or Gas Water Heaters – Easy DIY Water Heater Cleaning Tool

  • Sediment Removal Tool: Flushes and breaks up sediment buildup
  • Easy Installation: Threads onto drain valve with garden hose
  • Active Sediment Loosening: Uses air bursts to break up sediment during drain

As an affiliate, we earn on qualifying purchases.

As an affiliate, we earn on qualifying purchases.

Key Questions

How do I know if my tankless water heater needs cleaning?

If you notice decreased hot water flow, higher energy bills, or error codes, it may be time to clean your unit. Checking your owner’s manual for recommended maintenance intervals is also advised.

Can I clean my tankless water heater myself?

Yes, with proper tools and safety precautions, homeowners can perform a flush using a descaling solution like vinegar. However, following manufacturer instructions and consulting a professional if unsure is recommended.

What happens if I neglect annual cleaning?

Mineral buildup can reduce efficiency, cause the system to work harder, increase energy costs, and eventually lead to system failure or costly repairs. Regular maintenance helps prevent these issues.

Does hard water make cleaning more necessary?

Yes, areas with hard water experience faster mineral accumulation, making annual cleaning even more critical to maintain performance and longevity.

Are there signs of internal damage I should watch for?

Signs include inconsistent hot water supply, error messages, or unusual noises. If these occur, professional inspection and cleaning are recommended.

Source: Bob Vila

You May Also Like

How to Clean and Maintain Stainless Steel Appliances

Learn how to effectively clean and maintain stainless steel appliances to keep them shiny and scratch-free—discover essential tips you won’t want to miss.

Best DEWALT Power Tools for Auto Work (2026) — Guide 4

Discover the top DEWALT power tools for auto repair in 2026. Our roundup highlights the best drills and impact drivers for tight spaces and demanding tasks.

DEWALT Power Tools Maintenance: Essential How-To & Troubleshooting Guide

Learn practical, step-by-step maintenance and troubleshooting tips for your DEWALT power tools, ensuring safety and optimal performance.

DEWALT Power Tools Overheating: Causes & Troubleshooting Guide

Learn how to identify, troubleshoot, and fix overheating issues in DEWALT power tools safely and effectively with our step-by-step guide.