How To Flush A Tankless Water Heater

Have you recently installed a tankless water heater in Austin? If you have, you’ve probably heard how important it is to flush your heater at least twice a year. Flushing, also called water heater descaling, removes the mineral deposits left over from Austin’s exceptionally hard water, which can otherwise lead to lime-scale buildup on the inside of your water heater’s various pipes and parts. Left unchecked, lime-scale can cause many of the components inside your tankless water heater to work harder than necessary, shortening the lifespan of your system. 

If you are stuck wondering how to flush your tankless water heater in Austin, follow along as we explain how to do it properly! 

First Things First: Why You Should Regularly Flush Your System

One of the best ways to keep a traditional water heater healthy is to maintain it. Draining and flushing the system regularly helps prevent mineral buildup from negatively impacting its performance and shortening its overall lifespan. 

What many homeowners don’t know, however, is that tankless water heaters require the same level of care. To maintain their integrity, tankless water heaters need to be flushed every 12 months, and even more often if you live in a hard water area, like Austin, Texas. Flushing your heater is what will prevent lime-scale buildup on the inside of your system, which, left unchecked, can otherwise ruin the efficiency and effectiveness of your system.

Things to Keep in Mind Before You Flush

Look for Flush Valves

Something you should look for before you flush your tankless water heater are flush valves (also known as isolation valves.) Just like the valves on the back of your stove or toilet, these are valves that are installed for maintenance purposes only and often come in one of two types: rotary movement (such as a ball or butterfly valves) and linear (such as glove valves). These valves are important since they allow you to cut off liquid or gas from your appliances without having to shut off the entire supply. 

In the case of tankless water heaters, flush valves are especially important to have, since you’ll need to close the valves before you flush your system, so that the descaling solution doesn’t mix with the rest of the water in your house. That said, if your heater doesn’t have shut-off valves, it’s strongly encouraged that you hire a professional plumber who can safely perform your water heater flush without contaminating your system.

Essential Tools

Flushing a tankless water heater is a bit different from flushing a traditional system. Unlike draining and flushing a traditional water heater, which most homeowners can do with a few basic tools, you’ll need specialized equipment to properly clean your tankless system. Fortunately, you can often find many “flush kits,” available online that will generally include everything you need to flush your tankless water heater, such as hoses, buckets, and a circulation kit. These can be a great investment if you own a tankless unit.  

Read Your Manual

Before you do anything, it’s always best-practice to check your water heaters’ manual before you flush and descale, as some makes and models will have more specific instructions. Also, keep in mind that electric tankless water heaters may have different instructions for flushing than gas units, so be sure to check. 

How To Flush An Electric Tankless Water Heater

Here’s a general overview of how to properly flush your system.

As mentioned above, an important first step is to turn off both of the water intake valves (hot and cold) to your water heater. You should also turn off the gas or electric connection to the unit as well. Then, connect the hoses to your water heater’s inlet and outlet valves, the circulation pump to the inlet hose, and the other end of the outlet hose in the bucket that contains your cleaning solution.

Once everything is set up, open the water valves and start your circulation pump. Let it run for as long as your kit tells you to, or for one to two hours on average. Once the time is up, stop the pump and close the valves–you’re done.

Finally, you’ll want to clean your system by turning on the cold water intake valve and allowing tap water to move through the system. Wait for 5-10 minutes, then turn off the intake valve, and disconnect the remaining hoses. Last but not least, turn on the gas by opening the gas shut-off valve and reconnect the electrical supply. 

Get Your Tankless Water Heater Professionally Flushed in Austin

Flushing your tankless water heater is extremely important for maintaining the longevity of your system. By flushing your water heater at least twice a year, you can clear out the sediment buildup off the inside of the heat exchanger, increasing its efficiency, and ensuring it doesn’t have to work harder to heat your water. 

If you need a hand flushing your water heater in Austin, contact Stan’s today! We’ll schedule your water heater repair at a time that’s convenient for you, and send over an experienced plumber who can flush it for you. You’ll never have to worry about your chemicals mixing with your water, gathering all the essential tools, or overlooking any of the aforementioned steps. Plus, we’ll inspect and tune up your water heater for maximum efficiency and long term use—greatly increasing its lifespan and lowering your utility bills in the process. 

Contact Stan’s to schedule your tankless water heater repair in Austin today!

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