Tankless water heaters are known for their efficiency and long lifespan, but like any system, they need regular care to stay in peak condition. Over time, minerals from hard water build up inside the unit, coating the heat exchanger and restricting water flow. This not only reduces efficiency but can also shorten the life of your system.
Knowing how to clean a tankless water heater helps prevent these problems, and with just a bit of maintenance, you can keep your system running smoothly for years. That said, not everyone feels comfortable tackling this kind of project on their own—and that’s okay. A professional can handle tankless water heater flushing for you, ensuring it’s done safely and effectively.
How Often Should You Clean a Tankless Water Heater?
How often you clean your tankless water heater depends on the quality of your water supply. Homes with hard water will see faster mineral buildup than those with soft water. In general, most manufacturers recommend cleaning a tankless water heater once a year.
If you notice fluctuating water temperatures, reduced flow, or error codes, it may be time for a cleaning even sooner. And if you’re unsure how to begin, scheduling a professional service is always a safe bet.
Materials You’ll Need For Flushing Your Tankless Water Heater
If you’re comfortable with DIY, you’ll need a few basic tools and supplies before starting:
- Submersible pump
- Two clean hoses
- A five-gallon bucket
- White vinegar or a tankless water heater descaling solution
- Adjustable wrench
- Safety gloves and goggles
Gathering these materials ahead of time will help the process go smoothly. If you’d prefer not to buy or manage this equipment, a professional HVAC company can bring the right tools and expertise to handle it for you.
Step-by-Step Guide: How to Clean a Tankless Water Heater
Cleaning a tankless system is commonly referred to as “flushing” the unit. Here’s how the process works:
1. Power Down the Unit
Turn off the power supply to your water heater—either by switching off the breaker for an electric model or closing the gas valve for a gas-powered unit. Shut off the water supply valves to prevent water from entering during the cleaning process.
2. Connect the Hoses
Attach one hose to the cold-water service port and the other hose to the hot-water service port. Place both hose ends into a bucket. The pump will push vinegar through the cold-water inlet, circulate it through the unit, and return it through the hot-water outlet.
3. Add the Cleaning Solution
Fill the bucket with about four gallons of white vinegar or the recommended descaling solution. Avoid harsh chemicals—vinegar is safe, affordable, and effective for dissolving mineral buildup.
4. Start the Pump
Turn on the pump and allow the vinegar to circulate through the system for 45 to 60 minutes. This process breaks down scale deposits and restores efficiency.
5. Rinse the System
Once circulation is complete, empty the vinegar and fill the bucket with clean water. Run the pump again for about 10 minutes to rinse any remaining solution from the system.
6. Reconnect and Restart
Remove the hoses, close the service ports, and reopen the water supply valves. Restore power or gas to the system and run hot water at a faucet for a few minutes to ensure everything is working properly.
If this process feels overwhelming, a professional technician can handle tankless water heater cleaning for you and give your system a full inspection at the same time.
Benefits of Regular Cleaning
Taking the time to clean your tankless water heater—or scheduling a professional cleaning—offers many benefits:
- Improved Efficiency: Removing scale allows the unit to operate at peak performance.
- Longer Lifespan: Regular maintenance helps your system last 20 years or more.
- Consistent Performance: Say goodbye to fluctuating water temperatures.
- Lower Repair Costs: Preventive cleaning reduces the chance of expensive breakdowns.
DIY vs. Professional Cleaning
Some homeowners enjoy handling maintenance tasks themselves, but others prefer to leave it to the experts. If you’re not confident with plumbing connections or working around gas or electrical components, professional cleaning is the safest choice.
Hiring an HVAC technician also means your system gets a thorough inspection along with cleaning. This ensures small problems—like loose connections or minor leaks—are caught early before they turn into bigger, more expensive issues.
Schedule Professional Water Heater Service
Learning how to clean a tankless water heater is a valuable skill for homeowners, but it’s not something you have to do alone. Whether you handle the process yourself or call a professional, regular cleaning helps your system run efficiently, improves reliability, and extends its lifespan.
If you’d rather leave the job to trusted experts, MSCO Inc. Heating & Cooling is here for you. We’ve been serving Virginia Beach families since 1955 with reliable service, experienced technicians, and a promise of a pleasant customer experience every time.
Call MSCO Inc. Heating & Cooling today at (757) 427-0016 to schedule tankless water heater maintenance and enjoy worry-free hot water all year long.
