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Maximum Efficiency.
Powerful Performance.
Smart Control.

In Latin, “Maximus” means “the greatest,” and the Rheem® Maximus Super High Efficiency Gas Water Heater lives up to its name. It’s powerful enough to deliver dependable hot water, with unmatched efficiency in a residential gas water heater. So when you’re looking for a new water heater, choose the greatest.

Super-high efficiency operation delivers savings and a reduced energy and energy cost carbon footprint1
Heats water up to 2X faster,2 so you’ll have plenty of water to do the dishes, wash the laundry or even run continuous3 back-to-back showers
Exclusive technology provides control and alerts via both mobile device4 and full-color LCD display
Plumber-friendly design makes installation faster and more affordable with versatile and built-in features
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Unmatched Savings & So Much More

Save upfront and continue saving for years to come with the Rheem® Maximus Super High Efficiency Gas Water Heater. From big energy cost savings to installation savings and tax credits, everything about the Maximus is a win-win.

Maximum Efficiency

Super High Efficiency – High efficiency water heating with up to 0.90 UEF for carbon footprint and energy use reduction of up to 36%1

Cost-Friendly Upgrade – Take advantage of available tax credits or local utility rebates, and enjoy estimated energy cost savings of up to $1,100+ over 12 years5

Continuous Hot Water

Delivers Continuous Hot Water – Heats water up to 2X as fast as a standard gas tank2 so you’ll have plenty of water to do the dishes, wash the laundry or even run continuous3 back-to-back showers

MaxMode Gives the water heater the boost it needs to produce up to 15% more hot water and keep up, even if demand gets high—perfect for those weekends with house guests

Smart Controls

Integrated Wi-Fi – Real-time service alerts and control from anywhere with the EcoNet App4

Added Protection – Built-in 360° LeakSense water leak detection system detects any leak, large or small, internal or external6; plus Maximus is FVIR compliant

Hot Water Availability Indicator – Shower with confidence knowing there is enough hot water available

Leak Prevention – Available LeakGuard accessory stops water leaks before they become a problem, limiting leaks to 20 oz. or less7

Pain-free for Plumbers

0″ Clearance on Sides – Fits in a closet

Venting Versatility – Installs as Power Vent or Power Direct Vent, so you only have to carry one product on your truck

Startup Verification – Be sure your customer is up and running before you leave the home

Easy Diagnostics – View advanced diagnostic information8 and detect outgoing water temperature

Fast and Easy Service – Fully serviceable from the front

Did You Know?

Maximus qualifies for tax credits and rebates in addition to reducing energy use up to 36%.

Upgrading Is Easy

Making the switch to Maximus is simple. All Maximus Super High Efficiency Gas Water Heaters have zero side clearance requirement—making them easy to install even where space is a concern, like in a closet.

Knowledge is Power

With integrated Wi-Fi, homeowners can avoid cold showers, detect leaks and more. It’s all possible with Maximus Super High Efficiency Gas Water Heater and the EcoNet® App.4

Learn more about easy
homeowner financing options
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Degrees of Innovation
At Rheem, we focus on innovating with intent, engineering solutions with lifetime sustainability in mind—from material selection to smart features to responsible recycling
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Ready to get the continuous hot water you need with the efficiency and smart features you deserve?

Get Your Rheem Maximus Super High Efficiency Gas Water Heater Today