How to Flush a Tankless Water Heater

A tankless water heater is a marvel of modern plumbing technology, providing homeowners with endless hot water and energy efficiency. However, like any piece of equipment, it requires regular maintenance to ensure optimal performance and longevity. One crucial maintenance task for tankless water heaters is flushing the unit. In this blog post, brought to you by My Buddy the Plumber, we will walk you through the steps to effectively flush your tankless water heater, ensuring it continues to deliver hot water reliably.

Why Flush a Tankless Water Heater?

Over time, sediment, mineral deposits, and other impurities can accumulate inside a tankless water heater. This buildup can hinder the unit’s efficiency, reduce water flow, and even lead to malfunctions. Flushing the water heater annually helps to remove these deposits, preventing potential problems and preserving the system’s efficiency.

Step-by-Step Guide to Flushing a Tankless Water Heater

1. Turn Off the Power and Gas Supply

Before starting any maintenance on your tankless water heater, turn off the power and gas supply to ensure safety. Locate the electrical breaker dedicated to the water heater and switch it off. For gas-powered units, turn the gas valve to the “off” position.

2. Turn Off the Water Supply

Next, shut off the cold water supply valve that feeds into the water heater. This step prevents water from entering the unit while you’re flushing it.

3. Attach a Hose and Bucket:

Find the drain valve on your tankless water heater and attach a hose to it. Place the other end of the hose in a bucket or drain to collect the flushed water and debris.

4. Open a Hot Water Faucet:

To facilitate the flushing process, open a hot water faucet somewhere in your house. This will create a flow through the water heater and help push out the sediment and buildup.

5. Flush the System:

Now, it’s time to flush the tankless water heater. Locate the purge port valves on the unit (refer to the manufacturer’s manual for specific instructions). Use these valves to introduce a descaling solution or vinegar into the system. Allow the solution to circulate through the heater for the recommended duration, typically around 45 minutes to an hour.

6. Rinse and Clean:

After the flushing period, close the purge port valves and disconnect the hose. Turn on the cold water supply valve to rinse the system thoroughly. The descaling solution, along with the accumulated sediment, will drain out through the hose.

7. Close the Faucet and Reconnect:

Once the water runs clear, close the hot water faucet you opened earlier. Reconnect the power and gas supply to the water heater, and turn on the unit.

8. Check for Leaks:

Inspect all connections and valves to ensure there are no leaks. If you spot any, address them promptly to avoid potential issues down the line.

Conclusion: Flushing a Tankless Water Heater

Regularly flushing your tankless water heater is essential to maintaining its efficiency and prolonging its lifespan. By following the steps outlined in this guide, you can keep your tankless water heater running smoothly, providing you with endless hot water whenever you need it. Remember, if you’re uncertain about performing this maintenance yourself or encounter any problems, don’t hesitate to contact professionals like My Buddy the Plumber, who can provide expert assistance and ensure your tankless water heater stays in peak condition for years to come.