AO Smith Tankless Water Heater Reviews (2021 Edition)

Last Updated On October 19, 2021
ao smith tankless water heater reviews

Interested in purchasing an AO Smith tankless heater? 

AO Smith has established itself as the largest manufacturer of water heaters in North America. They make a wide variety of water heating products, including tankless water heaters. 

Tankless water heaters provide high-efficiency ratings and save space in your home, making them a more popular option for residential and commercial use. 

In this PlumbingNav guide, you will learn everything you wanted to know about AO Smith tankless water heaters and our picks for the top 5 AO Smith tankless water heaters currently on the market. 

Our Overall #1  Rated Top Pick for A.O. Smith

Updated On May 21, 2021

AO Smith ATI-540H Condensing Tankless Gas Water Heater

This power-vent, condensing gas water heater offers plenty of hot water for everyone in your family with a top flow rate of 9 GPM. You can use it all you want without creating high water bills since it has an exceptionally high efficiency rating of .93 UEF. You also get a 15-year limited warranty on the heat exchange and a 5-year limited warranty on the parts. 

Our Top 5Our Top 5 AO Smith Tankless Water Heaters for 2021

  1. AO Smith ATI-540H Condensing Tankless Gas Water Heater (Our #1 Overall Pick)
  2. AO Smith ATI-310U Non-Condensing Tankless Gas Water Heater (Best Non-Condensing)
  3. AO Smith Proline Electric Tankless 4 Chamber Water Heater (Best Electric)
  4. AO Smith ACT-199I-N Commercial Tankless Condensing Gas Water Heater (Best Commercial)
  5. AO Smith Proline R2VA-140E Electric Tankless Water Heater (Best Budget)

What's In This Guide?

      What Are The Advantages And Disadvantages Of A.O. Smith Tankless Water Heaters?

      Advantages:

      • Product Warranty 

      AO Smith believes in their products so much they include a warranty in case anything goes wrong. Warranties vary based on whether the unit uses gas or electricity. 

      Residential electric tankless water heaters come with a limited 5-year warranty on the heat exchange and a limited 1-year warranty on the parts. 

      Residential gas tankless water heaters come with a limited 15-year warranty on the heat exchange and a limited 5-year warranty on the parts. 

      • Company Community Engagement

      Most people want to buy from a company that plays an integral role in the community. AO Smith started the AO Smith Foundation in 1955 to support local communities. The AO Smith corporation contributes a portion of its profits to fund the organization and hosts various events to increase the influence of the charity. 

      did you know AO smith tankless water heaters

      Disadvantages:

      • Noisy

      Many AO Smith units make a significant amount of noise while operating. However, if you install the unit somewhere far away from work and study spaces, the noise should not interfere with daily activity during the day. 

      • Lack of Connectivity Options

      AO Smith does offer some products with advanced connectivity options that allow users to connect the device to the internet and monitor it from an app. However, the options are scarce compared to some of their competitors, such as Rinnai. 

      Many buyers want more smart water heater options since accessibility and easy usage monitoring can help users save money. 

      If you want to take advantage of AO Smith’s ICOMMTM Connectivity Platform, they come on all Cyclone® MXi commercial models. 

      Our AO Smith Tankless Water Heater Reviews

      AO Smith makes the following 5 tankless water heaters, but they still stand out through their unique features and uses. Read our reviews on the top 5 AO Smith tankless water heaters. 

      Our #1 Rated Pick: AO Smith ATI-540H Condensing Tankless Gas Water Heater

      AO Smith ATI-540H Condensing Tankless Gas Water Heater

      Our Overall #1 Pick

      This highly efficient, natural gas, condensing tankless water heater can provide unlimited hot water for up to three showers at one time with a maximum output of 9 gpm. If that still doesn’t provide enough hot water, connect it to up to four additional units with EZ link compatibility. 

      This indoor unit uses a power vent design and offers up to 50 feet of ventilation space so you can install it just about anywhere in your home. Advanced diagnostics to make troubleshooting a breeze. While this device uses natural gas, you can convert it to use propane.

      Pros

      • High .93 UEF efficiency rating
      • Power vent design for easy installation
      • Low-emissions

      Cons

      • Remote not included for indoor model
      • Expensive
      • Not suitable for outdoor use

      Our #2 Rated Pick: AO Smith ATI-310N Non-Condensing Tankless Gas Water Heater

      AO Smith ATI-310N Non-Condensing Tankless Gas Water Heater

      Best Non-Condensing

      This natural gas, non-condensing tankless gas water heater can provide unlimited hot water for up to two showers at one time with a maximum output of 8 gpm. 

      It uses a single copper heating element to heat the water with a low NOx emissions burner and an efficiency rating of .81. The unit ventilates the gas using a direct-vent design.

      Pros

      • Inexpensive, upfront cost
      • Small and lightweight 
      • Outdoor-friendly

      Cons

      • .81 UEF rating means higher utility bills
      • Direct-vent design limits install options
      • Non-condensing

      Our #3 Rated Pick: AO Smith Proline Electric Tankless 4 Chamber Water Heater

      AO Smith Proline Electric Tankless 4 Chamber Water Heater

      Best Electric

      This Proline electric tankless 4 chamber water heater supplies enough water for 1.5 bathrooms with 28,000 watts. The four heating element design runs at a high efficiency rating of .92 UEF. Powered by electricity, it does not require ventilation.

      Pros

      • .92 UEF rating
      • 4 Heating elements
      • Digital display

      Cons

      • Noisy
      • 5 year warranty
      • No WiFi/Bluetooth Connectivity

      Our #4 Rated Pick: AO Smith ACT-199I-N Commercial Tankless Condensing Gas Water Heater

      AO Smith ACT-199I-N Commercial Tankless Condensing Gas Water Heater

      Best Commercial

      InThis power-vent, condensing tankless natural gas water heater works perfectly for commercial use with a maximum flow rate of 10 GPM and 199,000 BTUs. Save money on your utility bills since this unit has an efficiency rating of .93 UEF. The first heat exchange is made from commercial-grade metal, and the second heat exchange is made out of stainless steel.

      Pros

      • .93 UEF 
      • Power-vent
      • 10 GPM

      Cons

      • High Maintenance
      • Heavy at 71 pounds
      • Regular maintenance required

      Our #5 Rated Pick: AO Smith R2VA-140E Electric Tankless Water Heater

      AO Smith R2VA-140E Electric Tankless Water Heater

      Best Budget

      This electric water heater uses two elements to heat the water with 14,000 kW, making it appropriate for about one shower at a time in cold climates. It runs at an efficiency rate of .84. The digital display makes it easy to read the temperature setting and change it. No moving parts reduce the amount of maintenance required. 

      Pros

      • Soft start feature ensures the unit won’t affect your electrical system
      • Scale-reduction technology
      • Easy to install

      Cons

      • Only suitable for 1 – 2 person household
      • .84 UEF rating (Not EnergyStar rated)
      • Not for outdoor use

      What Are The Key Features Of AO Smith Tankless Water Heaters?

      Learn what makes AO Smith Tankless water heaters stand out from conventional units by learning the key features. When you know what makes them unique, you’ll have the tools to make the best decision for you. 

      Small Size

      AO Smith tankless water heaters are easy to install in the most convenient location due to the small size. Some models can even fit in the crawl space or under the sink. This gives you the opportunity to place it as close to the most used fixtures and appliances in your home. 

      High Efficiency

      AO Smith tankless water heaters operate up to 34% more efficiently than conventional water heaters. Condensing units tend to provide the best efficiency ratings out of tankless options. Of course, each unit has a different rating, so compare models before you buy. 

      Instant Hot Water

      When you need hot water, you want it to continue to stay hot while using it. Tank-style units provide hot water until the tank runs out, but tankless units will stay hot since they heat the water as it’s needed. Just be sure to get a unit that has a high enough flow rate for your needs. 

      Our Overall Review Of AO Smith

      Reputable Company/Customer Service

      AO Smith has plenty of experience in the industry, and they used this experience to perfect their brand. AO Smith provides a wide number of water heating solutions, whether you prefer a tank, tankless, or hybrid unit. No matter what product you purchase, you know that it also comes with AO Smith’s dedication to the customer and emphasis on business ethics. 

      Before calling customer service, visit their website to read manuals on how to troubleshoot basic problems and answer questions. However, you can also fill out a form on the website, email, or call customer service during normal business hours to get a live person to help you. 

      Manufacturing Process:

      AO Smith originally had its headquarters in Milwaukee, WI, but it made a move to Ashland City, TN. In Tennessee, AO Smith created the largest water heater factory in the world. AO Smith continues its history of innovation and commitment to quality in the manufacturing process today, and continues to expand even through acquisition.

      Instead of merely focusing on safety and design with performance testing, AO Smith takes it one step further with extensive reliability testing of all its products at its one-of-a-kind Customer Experience Lab. 

      During testing, each device must prove its capabilities by running smoothly for 2500 cycles and having each component rigorously inspected.  

      Ease of Use: 

      AO Smith makes tankless water heaters as simple as possible. From installation to learning what an error code means, AO Smith provides plenty of resources for you to handle things yourself. Units with a digital display provide the easiest control. 

      Safety Issues:

      AO Smith makes efforts to create safe devices. In order to do that, here are some of the water heater safety features included in their products:

      • Air-fuel ratio (AFR) sensor
      • Water temperature safety control
      • Overheat cutoff fuse
      • Freeze protection

      Overall Effectiveness:

      You can trust you will have reliable hot water for your family when you purchase an AO Smith tankless water heater as long as you size the unit correctly. Gas tankless units offer a longer warranty, but electric tankless units are easier to install. 

      How Does A.O. Smith Compare Against Competitors?

      AO Smith is just one of many water heater manufacturers out there. Learn how AO Smith products and company culture stand up to some of its top competitors. 

      Is Rheem Better Than AO Smith?

      AO Smith makes reliable tankless water heaters at a reasonable price, and the parts are almost completely interchangeable. Rheem tankless water heaters come with a long life span and can hold up against the elements better. However, replacement parts must go through Rheem, and they charge more. 

      Is Bradford White Better Than AO Smith?

      AO Smith makes water heaters that last longer than Bradford White units with higher flow rates. However, Bradford White water heaters win slightly in efficiency and don’t make as much noise as AO Smith water heaters. 

      The Bottom Line On A.O. Smith Tankless Water Heaters

      AO Smith tankless water heaters provide a reliable hot water solution without the large tank. While not the most technologically advanced options on the market, they fit in most budgets and offer impressive efficiency ratings. 

      AO Smith FAQs

      Does AO Smith make tankless water heaters?

      Yes! AO Smith manufactures both gas and electric tankless water heaters for people looking for a tankless solution. They also make tankless water heaters designed for residential and commercial use.

      Are AO Smith tankless water heaters good?

      Yes! AO Smith tankless water heaters have a good reputation in the industry for quality, energy efficiency, and service. That’s why they are the #1 manufacturer of water heaters in North America. 

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