How Often to Flush a Tankless Water Heater

Tankless water heaters are a fantastic upgrade for any home, providing endless hot water while being more energy-efficient than traditional storage tanks. However, like any appliance, they require regular maintenance to work their best. One of the most important tasks is flushing the system. But how often should you do it, and why does it matter?

Why Flushing Your Tankless Water Heater Is Important

Over time, minerals from your water—especially if you have hard water—can build up inside your tankless system. This buildup, primarily composed of calcium and magnesium, can clog the heat exchanger, reduce efficiency, and even shorten the lifespan of the unit.

Flushing removes these deposits, keeping the system running smoothly and ensuring you get the best performance possible. It also prevents common issues like fluctuating water temperatures, reduced water pressure, and strange noises coming from the unit.

How Often Should You Flush Your Tankless Water Heater?

How often you flush your tankless water heater depends on the water quality in your area and how often you use your water heater.

• If you have hard water (high in mineral content), you should flush your system every six months to a year to prevent excessive scaling.
• If you have soft water or use a water softener, flushing once a year is typically sufficient.
• If your household uses a high amount of hot water, more frequent maintenance may be needed to keep up with the demand.

Checking your water heater’s manual is always a good idea, as manufacturers often provide specific guidelines based on their system’s design.

Signs Your Tankless Water Heater Needs Flushing

Even if you’re on a regular maintenance schedule, sometimes your water heater will show signs that it needs attention sooner than expected. Watch for these indicators:

• Fluctuating water temperatures – If your hot water suddenly becomes inconsistent, mineral buildup may be affecting the heat exchanger.
• Reduced water pressure – Scale can clog the pipes, leading to lower water pressure throughout your home.
• Odd noises – If you hear crackling or popping sounds, that’s a sign minerals are interfering with the heating process.
• Error codes – Many modern tankless water heaters display error messages when maintenance is needed.

If you notice any of these signs, flushing the unit as soon as possible can help prevent larger problems down the line.

How to Flush a Tankless Water Heater

Flushing a tankless water heater is a bit different from flushing a traditional tank system. The process usually involves shutting off the power and water supply, connecting hoses to the unit, and running a descaling solution or white vinegar through the system to remove buildup.

If you’re comfortable with DIY maintenance, you can follow the instructions in your owner’s manual. However, it’s typically best to schedule professional water heater maintenance to ensure the job is done safely and correctly.

Keep Your Tankless Water Heater in Top Shape

Regular maintenance keeps your tankless water heater working efficiently, helps lower energy costs, and extends its lifespan. If you’re due for a water heater flush or want to schedule professional maintenance, Schaal Plumbing, Heating & Cooling is here to help. Our team of experts ensures your system stays in peak condition, so you can enjoy hot water without worry.

Call Schaal today to schedule an appointment!