An AO Smith tankless water heater comes from one of North America’s largest water heater makers, and Takagi is a long-standing Japanese tankless brand. Here’s what to know about each.
A.O. Smith, headquartered in Wisconsin, makes tank, tankless, heat pump and commercial water heaters. Its tankless lineup includes:
Model numbers often include fuel and venting information. Always check the specification sheet for flow at your temperature rise.
An AO Smith electric tankless water heater is available for point-of-use and small whole-house needs, and you’ll also see AO Smith instant water heater and AO Smith tankless heater used for the same products. A State tankless water heater is part of the same family.
| Brand | What it’s known for |
|---|---|
| State Water Heaters | Professional-channel tank and tankless models |
| American Water Heaters | Residential tank and tankless products |
| Lochinvar | High-efficiency boilers and commercial water heaters |
Many shoppers also search for an American Standard water heater; American Standard water heaters are a different brand from American Water Heaters, so compare specifications and warranty terms directly.
A Takagi tankless water heater is a common choice among installers who want a straightforward, serviceable unit.
Takagi is a Japanese tankless water heater brand with a long history in the U.S. market. Its range includes:
Compare A.O. Smith and Takagi models with Rinnai, Navien and Noritz on:
See our best tankless water heaters and other brands compared.
See current listings with BTU, flow, venting and condition.
A.O. Smith is one of the largest water heater manufacturers in North America with a broad service network. Its tankless range includes condensing and non-condensing gas units and electric models.
State Water Heaters is an A.O. Smith brand. Models across A.O. Smith brands often share designs, but names, features and warranties can differ. Compare the spec sheets.
No. American Water Heaters is an A.O. Smith brand, while American Standard is a different brand name. Check the manufacturer listed on the rating plate and warranty.
No. EZ Tankless is a separate brand known for portable and point-of-use propane units.
This guide is general information for U.S. homeowners, not professional advice. Gas, electrical and venting work must follow the manufacturer’s instructions and local codes, and in most areas requires a licensed plumber, electrician or gas fitter and a permit. Specifications and prices change; always confirm details on the product page and in the installation manual.