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How to Maintain Your Tankless Water Heater

Tankless water heaters are one way homeowners can save energy.

Instead of heating tanks of water in batches, a tankless water heater, or on-demand water heater, warms up water as it's needed. Depending on how many gallons of hot water your home uses per day, a tankless water heater can be 20 to 30 percent more efficient than a normal hot water heater.

Like any other new piece of equipment in your household, it's important that you understand how to best take care of it. Neglecting basic maintenance won't allow your tankless water heater to operate at its full potential, and won't allow you to achieve the energy savings you likely were looking forward to when you chose it.

Flush to remove hard water deposits

Your tankless water heater should be flushed at least annually. This is to remove mineral deposits, such as calcium. If you've had hard water problems in your home, you might consider flushing out your heater more than once per year to counter mineral deposits.

To flush your heater, first you must check your owner's manual to see if your unit needs to have the power shut off. If your heater is electric, turn off the power from the breaker panel, and if it's gas, rotate the gas cutoff until fuel is no longer going to the heater.

Next you will want to turn off the water supply bringing cold water to the heater, as well as the valve sending hot water out.

Fasten a six-foot garden hose to a sump pump, and the other end to the cold-water valve. A second garden hose will have to be connected to the hot-water valve, with the opposite end submerged in a five-gallon bucket of distilled white vinegar. Place the pump line in the bucket as well.

Use the pump to circulate the vinegar through the heater. The vinegar will break down mineral deposits and buildup. Let the pump run for about 1.5 hours. Then replace the vinegar with cold water. Use this to rinse out your heater.

Once the heater is clean, you'll have to clean the inlet filter screen. To do this, simply rinse it and take away any sediment stuck to it.

Once the screen is clean and the heater is all flushed out and rinsed, you can replace everything back to working order. Test the faucets throughout your home to make sure there isn't any air trapped in them. Let the water run for a few minutes to remove any air pockets.

Again, refer to your owner’s manual for some procedures may vary.

If you have problems with your tankless water heater, you may want to call in the experts. Contact your local Roto-Rooter to make sure everything is in working order.

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