When deciding a water heater for your home, office, or any other space; there is a usually a toss between two water heater companies- Rheem and AO Smith. Both are the popular water heater brands of U.S. They manufacture top quality water heaters intended for both residential as well as commercial purposes.

With a neck to neck fight between both of them, which water heater brand you should opt for? To ease your decision-making process, take a closer look at their product line, price, quality, warranty, design, energy efficiency, and storage.

Rheem Vs AO Smith Comparison

Let’s Dive Deep To Get Acquainted With Their Telling Differences And Learn How These Two Popular Are Frequently Compared Water Heaters.


Rheem, a remarkable water heater brand was devised by two brothers- Richard and Donald Rheem. Since its inception, there has been no turning back. The brand is evolving and coming up with a diverse range of products with each passing day.

It always focussed on quality over profit. Consequently, it became a worldwide popular brand.

AO Smith, a leader in supplying commercial as well as residential water heater products. This tank-based water was brought into being by Olivier Smith in 1921. Its performance is undoubtedly surpassable. With the passage of time, the brand has also devised tankless heaters.

Energy efficiency:

Rheem tanked and tankless water heaters have Uniform Energy Factor(UEF) as the rating measure for their energy efficiency. Some of its renowned energy-efficient models are:-

  • Professional Prestige Series

  • Performance Power Direct Vent 50 Gallon Gas Water Heater

  • Performance High-Efficiency Condensing Power Direct Vent

AO Smith has UEF as the rating measure for the energy efficiency of their tank as well as tankless water heater models. They have also got Energy Star ratings. Some of its renowned energy-efficient tanked heaters models are:-

  • Polaris® High-Efficiency GSP 100 (LP)

  • Vertex™ 100 Power Direct Vent Propane Water Heater

  • ProLine® XE SL Power Vent 50-Gallon Gas Water Heater

rheem vs ao smith water heater


The warranty policy of Rheem water heaters encompasses support, warranty services, and an extended warranty option too. Its warranty period starts from 6 years that can be extended upto the period the purchaser owns the home where the unit is installed.

AO Smith offers unparalleled warranty services. It provides an up to 12 years warranty on its both tanked as well as tankless models. It is well-known for its satisfactory customer services, whereas Rheem lacks in this aspect.

Product Line:

Rheem is known for producing 15 tanked water heaters of electric type, and 43 tanked water heaters of gas-type. Apart from this, it also manufactures three kinds of tankless heaters for residents.

Its products are good and can easily fit one’s pocket. It also manufactures many other broad range of products including air conditioning, heating, and cooling systems.

AO Smith being solely focused on water heaters manufactures 270 models of tanked water heaters. 66 of them are electric tanked water heaters, where 206 of them are of gas-driven models.

In addition to this, it also has 51 tankless water heaters in its product line from which 18 of them are electric, and 33 of them are gas-powered. You can easily select your desired model from its extensive portfolio of heaters.

Design And Installation:

When it comes to design, Rheem never fails to surprise the people with its innovative crafted water heater models. Here are some of the models that have topped the list in terms of novel design.

These are as following- Gladiator Water Heater, Smart Thermostats, and Condensing Tankless Heaters.

When it comes to installation, Rheem has ‘Find A Pro’ service that connects the buyer and any independent Rheem serviceman within 25 miles.

AO Smith not so attractive models don’t appeal people at the very first look. However, they are known for a diverse range of product design.

When it comes to installation, AO Smith too offers ‘Find a Pro’ service upto 100 miles. The best part is that its installation service is more reliable than Rheem’s service.


Upon closer inspection, it is apparent that both the leading brands of water heater possess individual distinctions. Their products are built to last for a prolonged period of time.

They have their own pros and cons. Rheem is manufactured to quickly adapt to the solar system which makes them a durable and reliable choice for homeowners. On the other hand, it lacks up to the mark customer service.

AO Smith is a proud manufacturer and has gained remarkable attention for coming up with a diverse range of tanked as well as tankless water heaters. Depending upon your needs and requirements, make an informed choice by carefully inspecting each brand’s specifications.

Frequently Asked Questions

Q4. What Is The Best Rheem Electric Water Heater?

Till date, the best Rheem electric water heater is the Rheem RTEX-18 Electric Tankless Water Heater.

Q3. How long do a Rheem and AO water heater last?

A Rheem water heater usually lasts for 12 years. However, the lifespan varies upon the model, energy supply and level of usage. On the other hand, AO Smith water heaters last for about 10-15 years.

Q2. In terms of customer service, which US brand of water heater outperforms another?

Both AO Smith and Rheem offers ‘Find A Pro’ services. However, only the former one takes liability to train the contractors up. If you are an owner of Rheem water heater, you are prone to bear the damage cost in case of inconvenience caused.

Q1. Which is the better choice for gas water heaters- AO Smith or Rheem?

AO Smith is the better choice for gas water heater but only by a fraction. However, Rheem is a preferred choice of buyers who wish to purchase Electric Tankless Water Heaters.