The Best AO Smith Gas Water Heaters to Buy for your Home

A review of the best AO Smith gas water heaters to buy for residential homes and features to look for. Check out both tankless and conventional tank-type heaters with the advantages and benefits of both. See the differences between cheaper and expensive gas models.

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AO Smith gas water heaters: Model review

As the list of gas-powered water heaters from AO Smith is long, this review will cover only the best and most advanced models. It is meant for those homeowners looking either for an affordable one or shopping for the most advanced models with state-of-the-art design.

There are several categories you can select from:

  • Proline
  • ProLine Master
  • ProLine High Recovery
  • Polaris
  • Vertex
  • Tankless

Most of the above gas water heaters with storage tanks come with a warranty of 6 and 8 years, energy efficiency up to 0.69, and are used for small to mid-size homes.

The best models, such as Polaris and Vertex models come with a 10-year warranty, and since they have powerful and high-performance burners they are mostly used in average and large homes with 3-4 showers.

Tankless water heaters are available as non-condensing and condensing, heating water on demand and delivering hot water in continuous supply to up to 3 showers working simultaneously. They have the longest warranty of all gas water heaters - 15 years.

Popular 50-gal models to buy

  • Vertex GDHE-50
  • Effex
  • GCR-50 ProMax Plus High Efficiency

Features and benefits

AO Smith gas water heaters come with many useful features where some are more and some less advanced. As explained in this article, the main features that are included in most models are:

  • Blue Diamond glass coating - provides tank protection against corrosion.
  • Coregard anode rod - also protecting the metal tank. Advanced anode protection is only available on models with 8 and 10 years warranties.
  • Self-cleaning dip tube - reduces the sediment build-up.
  • Self-powered electronic gas valve used for enhanced performance and diagnostics.
  • Low NOx gas burner to reduce gas emission.
  • Heat traps for reducing energy waste.
  • Brass drain valve for longer life.

Best AO Smith gas water heaters to buy

The best gas water heaters from AO Smith are designed with commercial-grade components and include condensing technology, advanced diagnostics, high or continuous water flow rate, state-of-the-art technology, superior high efficiency, and ultra-low gas emission for better environmental protection.

These models are coming from the ProLine XE series, as shown in the review of 50-gal units below:

Vertex Power-Vent GPHE-50

  • Helical internal heat exchanger increases the energy efficiency to over 90%, which is higher than the efficiency found on conventional models.
  • Side-mounted recirculation taps for combined space and potable water heating.
  • Intelli-vent gas valve with the premium-grade hot surface ignitor for durability, precise temperature control, and diagnostics.
  • Two heavy-duty anode rods for better corrosion resistance.
  • High first-hour rating of 119 and recovery rate of 92 gallons.

Vertex Power-Direct GDHE-50

  • Helical internal heat exchanger and condensing design for the efficiency of 96%.
  • Side-mounted recirculation taps for combination space and potable water heating.
  • Advanced electronic control with LCD display, diagnostics, and iCOMM for remote control.
  • First hour rating of 100 gallons.


  • Condensing design and 96% thermal efficiency.
  • Modulating gas burner for lower energy consumption and increased comfort.
  • Helical internal heat exchanger.
  • Stainless steel construction for durability.
  • Advanced electronic control with the large LCD display.
  • Recovery rate of over 129 GPH.
  • First hour rating is over 179 gallons.
  • Several models available with the power from 100,000 to 199,000 BTU, and two tank sizes of 34 and 50 gallons.
  • 10-year warranty.

Best affordable gas models to purchase

High-Efficiency Power Vent

  • Versatile power vent system with the 3-position rotatable blower outlet.
  • System against flammable vapors.
  • Hot surface ignitor.
  • Improved gas valve design with LED.
  • Energy Star compliant.
  • Side connection.
  • First hour rating of 108 GPH.

ProLine XE - High-efficiency Ultra-Low NOX

  • Intelli-Vent gas control with the ultra-low NOx combustion.
  • Power venting with flexible thru-the-wall and thru-the-roof vent pipes.
  • High efficient and Energy Star compliant.
  • Enhanced-flow brass drain valve.

Top tankless models to buy

AO Smith tankless water heaterAO Smith tankless water heater

The best AO Smith gas water heaters with the tankless design utilize the following features; two strong and ultra-efficient heat exchangers, condensing technology for the ultra-high energy efficiency of 0.95, built-in recirculation pump for faster hot water delivery, and ultra-low NOx for less pollution.

All models are from the ProLine XE series.

The most powerful tankless model is ATI-540H, designed to deliver up to 10 GPM of hot water, enough to supply hot water to homes with up to 4 showers, or even more when using an Easy Link or Multi-Unit system.

This tankless unit is small and compact and can be installed indoors with the power or power-direct venting system or outdoor, as ventless. It is also smart where the built-in advanced electronics monitor the whole operation while helping with the diagnostics system for easier troubleshooting.

All the tankless units are equipped with the safety elements to protect the system from extreme temperatures, pressure, and freezing, while the long warranty of 15 years provides a peace of mind to the owners.

How to contact AO Smith:

Official website: hotwater.com

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