I’ve worked with both Rheem and A.O. Smith water heaters, and when it comes to choosing between these two giants, the decision can get tricky. Both brands have long-standing reputations for reliability, energy efficiency, and a range of options—whether you’re looking for gas, electric, tank, or tankless water heaters. But there are differences that can make one better suited for your needs over the other.
Here’s a full breakdown based on real-world experience, performance, and user feedback to help you decide which brand is the better choice for your home.
Rheem Water Heaters: Key Features
1. Types of Water Heaters
Rheem has a wide selection of models that fit a variety of needs:
- Tank Water Heaters (Gas and Electric):
Available in 40 to 50 gallons for most homes. The Performance Platinum series is one of their most popular, offering high efficiency and durability. - Tankless Water Heaters:
Rheem’s tankless options are well-known for delivering endless hot water and come in both gas and electric models. The Rheem Performance 27 kW electric tankless heater is a favorite among homeowners looking for compact solutions. - Hybrid (Heat Pump) Water Heaters:
Rheem’s Performance Platinum Hybrid water heater is one of the most energy-efficient models on the market. It can cut down your energy bills significantly while still delivering reliable hot water.
2. Energy Efficiency
Rheem has some of the best energy efficiency ratings in the industry. Their hybrid models are particularly energy-efficient, with Uniform Energy Factors (UEF) as high as 3.50, meaning they can be up to four times more efficient than standard electric water heaters.
- Tank Models: Rheem’s gas and electric tank models are ENERGY STAR certified, with UEFs ranging from 0.67 to 0.80.
- Tankless Models: Rheem’s tankless water heaters are highly efficient, with gas models boasting up to 0.96 UEF, and the electric versions also offer significant energy savings over time.
3. Durability and Warranty
Rheem water heaters are built to last, especially their Performance Platinum series, which comes with 12-year warranties. Their stainless steel components and glass-lined tanks ensure resistance to corrosion, which prolongs the lifespan of the unit.
- Warranty: Rheem offers 6 to 12-year warranties on most of its water heaters, with the hybrid models offering longer coverage.
4. Installation and Maintenance
Rheem water heaters are designed with ease of installation in mind. Their electric and hybrid models are more DIY-friendly, while gas and tankless units often require professional installation, especially if venting or gas lines need upgrading. Maintenance is generally straightforward, especially with their Wi-Fi-enabled models, where you can monitor the system via a smartphone app.
Popular Rheem Models
| Model | Type | Capacity/Flow Rate | Energy Factor (UEF) | Best For |
|---|---|---|---|---|
| Rheem Performance Platinum 50 Gal | Hybrid (Electric) | 50 gallons | 3.50 | Large homes, high energy savings |
| Rheem Performance 27 kW Tankless | Electric | 5.0 GPM | 0.93 | Small to mid-sized homes |
| Rheem Professional Prestige Gas 50 Gal | Gas Tank | 50 gallons | 0.67 | Medium homes, reliable performance |
A.O. Smith Water Heaters: Key Features
1. Types of Water Heaters
A.O. Smith also offers a comprehensive selection:
- Tank Water Heaters (Gas and Electric):
A.O. Smith is known for its ProLine series, which includes durable gas and electric tank models ranging from 40 to 50 gallons. - Tankless Water Heaters:
A.O. Smith’s gas-powered tankless models are highly regarded, offering endless hot water with impressive flow rates of up to 10 GPM. They also offer electric tankless models, though they are less common than gas. - Hybrid (Heat Pump) Water Heaters:
Their Voltex Hybrid series is among the top-tier heat pump water heaters, known for high energy efficiency and large capacity. It’s ideal for homeowners looking to save on energy bills while still having plenty of hot water.
2. Energy Efficiency
A.O. Smith is equally competitive when it comes to energy efficiency, with a focus on long-term savings:
- Hybrid Models: Their Voltex Hybrid models offer up to 3.45 UEF, which is similar to Rheem’s hybrid series in terms of efficiency.
- Tank Models: A.O. Smith gas and electric tank water heaters have UEFs ranging from 0.62 to 0.74, depending on the model. Their ProLine XE series is ENERGY STAR certified and designed for higher efficiency.
- Tankless Models: A.O. Smith’s tankless gas models feature UEFs of up to 0.95, providing homeowners with energy-efficient options for reducing gas bills over time.
3. Durability and Warranty
A.O. Smith focuses heavily on durability. Their CoreGard™ anode rods and glass-coated tanks provide superior corrosion resistance, extending the life of the heater. Their ProLine XE models come with enhanced durability and are specifically designed for harder water environments, making them a great choice for homes in areas with mineral-heavy water.
- Warranty: A.O. Smith water heaters come with 6 to 12-year warranties, similar to Rheem. They also offer extended warranty options for certain models, making them competitive in terms of protection.
4. Installation and Maintenance
A.O. Smith’s electric tank models are generally easy to install, while gas and tankless models typically require professional installation due to venting and gas line requirements. One unique feature is their Blue Diamond® glass coating on tank models, which helps reduce corrosion and the need for frequent maintenance. For tankless models, regular descaling is recommended, especially in areas with hard water.
Popular A.O. Smith Models
| Model | Type | Capacity/Flow Rate | Energy Factor (UEF) | Best For |
|---|---|---|---|---|
| A.O. Smith Voltex Hybrid 50 Gal | Hybrid (Electric) | 50 gallons | 3.45 | Large homes, energy savings |
| A.O. Smith ProLine XE Gas 50 Gal | Gas Tank | 50 gallons | 0.74 | Mid-sized homes, high performance |
| A.O. Smith ATI-540H-N Tankless Gas | Tankless Gas | 10 GPM | 0.95 | Larger homes, endless hot water |
Rheem vs. A.O. Smith: Side-by-Side Comparison
| Feature | Rheem | A.O. Smith |
|---|---|---|
| Energy Efficiency | Hybrid models have UEF up to 3.50 | Hybrid models with UEF up to 3.45 |
| Tank Durability | Stainless steel and glass-lined tanks | Blue Diamond® glass coating, durable anodes |
| Tankless Options | Gas and electric, UEF up to 0.96 | Primarily gas, UEF up to 0.95 |
| Warranty | 6 to 12 years, depending on the model | 6 to 12 years, with extended warranty options |
| Installation | DIY-friendly for electric models | Slightly more complex installation for gas models |
| Best Model | Rheem Performance Platinum Hybrid 50 Gal | A.O. Smith Voltex Hybrid 50 Gal |
Pros and Cons of Rheem Water Heaters
Pros:
- Energy-efficient hybrid models save significant energy over time.
- Wide range of options, from tank to tankless.
- Wi-Fi connectivity on some models for easy control and monitoring.
- Strong warranties on premium models.
Cons:
- Some tank models have slower recovery times compared to competitors.
- Higher initial cost for hybrid and tankless models.
Pros and Cons of A.O. Smith Water Heaters
Pros:
- Excellent durability, especially for homes in hard water areas.
- ProLine XE series offers high efficiency at a moderate price.
- Tankless models offer high flow rates, perfect for larger households.
- Affordable electric tank models for smaller budgets.
Cons:
- Fewer electric tankless models compared to Rheem.
- Some users report slightly more expensive installation for gas models.
Final Verdict: Rheem or A.O. Smith?
Both Rheem and A.O. Smith offer reliable, energy-efficient water heaters, but your choice will depend on your specific needs:
- If energy efficiency is your top priority, and you want smart features like Wi-Fi control, Rheem’s hybrid models are your best bet. Their Performance Platinum series is unmatched for savings and convenience.
- For durability and tough conditions (like hard water areas), A.O. Smith has the edge. Their Blue Diamond® coating and ProLine XE series offer strong protection and long-lasting performance.
In summary, you can’t go wrong with either brand, but Rheem is ideal for homeowners looking for cutting-edge tech and efficiency, while A.O. Smith excels in durability and performance, especially for those in challenging water environments.