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Tankless Water Heaters


#1 in Tankless Water Heater in North America

Your Central Texas Rinnai Pro

At OnCall Plumbing we are Rinnai Pros. We specialize in Rinnai tankless water heater installation.


More homeowners and business owners choose Rinnai than any other tankless water heater brand. They choose Rinnai for their 100-year commitment to quality, for their industry-leading warranties, and because they are the first major tankless brand assembled in the U.S.A.

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How Tankless Works

With a tankless water heater, your Texas home's cold water is heated only when you need it, and it stays hot until you're done using it. This results in a limitless hot water supply and little to no wasted energy usage.

No-Hassle Hot Water, When and Where You Need It

  1. Flame ignites and heats two heat exchangers

  2. Water preheats as it passes through the secondary heat exchanger

  3. Water continues to heat to desired temperature as it passes through stainless steel primary heat exchanger

  4. Water exits the unit and travels to the water fixture where it is needed

  5. Flame output adjusts as needed to maintain water temperature during use

  6. With usage complete, the flame turns off and water stops flowing

Contact us today for your tankless water heater installation.

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Austin, TX, 78748

Office Hours: 8am-5pm Monday - Friday



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