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Tankless Water Heater Maintenance: A Guide for Homeowners

A tankless water heater, like this one, can supply your home with energy-efficient water heating for years to come.

So you’ve decided to go tankless. A tankless water heater that is.
Tankless water heaters save money in the long run, running more efficiently than bulky tank water heaters.

A tankless water heater is a great option for providing you with a steady stream of hot water. It takes up less room than a tank heater, and it lasts almost twice as long on average. You also do not end up with a surprise puddle when your tank cracks and fails you.
More homes than ever have adopted tankless water heaters because of their efficiency and longevity. Keep reading to learn about how tankless water heater maintenance will keep your water heater running efficiently for decades.

Basic Tankless Water Heater Maintenance Steps

A tankless water heater, like any water heater, is an investment. The more you care for it, the longer it will last. Tankless water heaters malfunction when you neglect them, leaving you with tepid and sometimes even cold water.
This tankless water heater maintenance checklist will help your water heater last a long time.

1. Turn Off Your Power

Before you inspect your tankless water heater, turn off its power source. Electricity or gas typically powers a tankless water heater. However, some heaters will use propane or kerosene.
If you turn off the main gas outlet or electricity source by flipping the main circuit breaker, you will ensure that you’re safe as you inspect the water heater.

2. Close the Water Valves

Close the valves near your tankless water heater to prevent water from entering the heater while you’re working on it. A closed valve also prevents hot water from leaving the water heater as you clean it.

You will typically have three water valves, and they are color-coded. The blue valve is for cold water, the red one is for hot water, and the other valve is for the main water supply coming into your home. Close all of these valves before you touch your water heater.

3. Relieve Pressure

At this point, you will relieve the pressure in your water heater. This action keeps hot water from rushing out of the water heater and burning you in the process of flushing the line.

Locate the purge valves. This looks like a cap with a little T-shaped handle. You can relieve the pressure buildup by pulling up on the T-shaped handle.

When you do this, you relieve the pressure in the heater.

4. Attach Hosing Line

Consult your tankless water heater manual. See where you can attach hosing when you’re flushing the line.

Most tankless water heaters come with hosing lines. If you inherited your tankless water heater with your house then you may need to buy some from a local hardware store.

After you’ve located your hose, connect the water heater to a sump pump or bucket. The hosing will let the cold and hot water valves discharge and empty from the water heater.

When port valves are closed, they are parallel to the valves. Thus, turn your valves so they are perpendicular. This action releases the water in the unit.

5. Descale the Unit

If you have hard water, minerals will build up in your tankless water heater. They eventually will clog the heater. A commercial descaling solution or a white vinegar solution will remove these minerals and keep your tankless water heater running smoothly.

To make the white vinegar solution, add approximately two and a half gallons of white vinegar as an organic descaler directly into the tankless water heater.

6. Flush the Water Heater

Once you have all of the materials in place, follow the instructions in your tankless water heater. The water heater should drain for around 45 minutes to have a thoroughly clean unit. After the water heater finishes draining, close the valves and disconnect the hoses.
Then reseal the purge valves with the port caps.

7. Restart Your Heater

After you have flushed the water heater, restart the water heater unit. Consult your manual once again for the specifics on how to flush the water heater. The restarting process should include turning the valves on and turning the power source back on.

When you turn your valves on, air will go through your after pipes. Turn on your faucets, and they will spurt air for a couple of minutes. Eventually, water will flow freely.

Benefits of Maintaining a Tankless Water Heater

If you maintain your tankless water heater properly, you can hope for it to last a long time. Typically, a tankless unit lasts around 20 years. A typical storage water heater, in contrast, lasts only 10 to 12 years.

You can prolong your water heater’s life expectancy by periodically flushing the line.

You can also hope your water heater will perform better as time passes. If you keep it maintained during its lifespan, the tankless water heater will perform optimally. This will keep your water heating bills low and flow rates high.

Every time you flush your tankless water heater, you’re removing the minerals that could slow down the flow. Regular maintenance will keep the mineral build-up at bay and the water flowing freely.
Furthermore, you lower the risk of premature failure. Magnesium and calcium deposits will damage a tankless unit’s heat exchanger. As a result, you’ll have to replace the entire unit sooner than if you had just flushed the unit regularly.

If you have soft water or just average water, plan on flushing your unit once a year. If you have hard water, flush it more often. Make it a habit to flush it whenever you change your clocks over for daylight savings time.

This way, you will ensure that you’re flushing it regularly.

Don’t Neglect Tankless Water Heater Maintenance

If these steps sound intimidating, call a professional. At any point in the process, you could damage your water heater. So it’s always best to let a professional plumber do the job.

Proper tankless water heater maintenance will ensure you get the most out of your water heater investment. Flush the line at least once a year to keep minerals and scaling at bay.

Do you need a plumbing, cooling, and heating expert? We do it all, from air conditioning to furnaces to water heaters. We have been serving clients all over Chicago’s south suburbs since 1968.
Give us a call today, and let us take care of you.