The Best Rheem Natural Gas Tankless Water Heaters: Reviews & Guide

Hot water is a necessity for most households, whether you’re showering, washing dishes, or doing laundry. Running out of hot water mid-shower can be frustrating, especially during peak usage times. Traditional tank water heaters can leave you waiting for the tank to refill, but tankless systems offer an efficient solution. With Rheem’s natural gas tankless water heaters, you can enjoy a continuous supply of hot water, eliminating the wait and ensuring comfort for your family.

Choosing the right tankless water heater involves understanding your specific needs, including how many gallons per minute (GPM) you require and the energy efficiency of the unit. Rheem’s reputation for quality and innovation makes their products stand out in the market. Their natural gas tankless water heaters provide robust performance, making them suitable for large households and high-demand situations.

This roundup highlights the best Rheem natural gas tankless water heaters available. Each model offers unique features, ensuring you find a perfect fit for your home.

Here’s a quick comparison of the key specifications of our top picks:

Features	Rheem RTG 7.0 GPM	Rheem RTG 8.4 GPM	Rheem RTG 9.5 GPM	Rheem RTG 7.0 GPM Outdoor	Rheem RTG 8.4 GPM Indoor
Max Output	160,000 BTUs	180,000 BTUs	199,900 BTUs	160,000 BTUs	180,000 BTUs
GPM	7.0 GPM	8.4 GPM	9.5 GPM	7.0 GPM	8.4 GPM
Installation Type	Indoor	Outdoor	Indoor	Outdoor	Indoor
Energy Factor	0.82 UEF	0.82 UEF	0.82 UEF	0.82 UEF	0.82 UEF
Warranty	15 years	15 years	15 years	15 years	15 years

Rheem RTG Series 7.0 GPM…

The Rheem RTG Series 7.0 GPM Natural Gas Tankless Water Heater is designed for households that require a reliable supply of hot water without the bulk of a traditional tank. This model delivers an impressive 7.0 GPM at a 35°F temperature rise, making it ideal for families with 2-3 bathrooms. It’s particularly effective for simultaneous usage, such as taking a shower while running the dishwasher.

A standout feature of this model is its energy efficiency. With a Uniform Energy Factor (UEF) of 0.82, it provides significant savings compared to traditional electric tank heaters. Buyers appreciate the compact, wall-mount design that saves space and the advanced safety features that include leak detection and flame failure protection.

However, while it serves most households well, larger families with higher simultaneous demands might find themselves needing a more powerful unit. If you’re only using a single water point at a time, this model shines, but peak times may exceed its capabilities.

• Max output: 160,000 BTUs
• Flow rate: 7.0 GPM
• Indoor installation
• Energy Factor: 0.82 UEF
• 15-year warranty on heat exchanger

Best for: Medium-sized families needing reliable hot water.

Rheem RTG Series 8.4 GPM…

The Rheem RTG Series 8.4 GPM Natural Gas Tankless Water Heater is a robust choice for larger households. With a maximum output of 180,000 BTUs and a flow rate of 8.4 GPM, this unit can comfortably handle multiple hot water demands simultaneously, making it suitable for 3-4 bathrooms in use at once.

This model excels in energy efficiency, similar to other Rheem offerings, allowing homeowners to save on energy costs. It is designed for outdoor installation, eliminating the need for venting and providing flexibility in placement. Users appreciate its durable construction and the peace of mind that comes from its safety features, including built-in freeze protection.

One limitation to consider is that outdoor installation may not be feasible for everyone, particularly in colder climates where freezing temperatures can be a concern. Additionally, professional installation is recommended to ensure proper setup and functionality.

• Max output: 180,000 BTUs
• Flow rate: 8.4 GPM
• Outdoor installation
• Energy Factor: 0.82 UEF
• Industry-leading 15-year warranty

Best for: Large families needing high hot water output.

Rheem RTG Series 9.5 GPM…

The Rheem RTG Series 9.5 GPM Natural Gas Tankless Water Heater is the powerhouse model for those who need maximum performance. With a staggering 199,900 BTUs and a flow rate of 9.5 GPM, it’s perfect for larger homes with multiple bathrooms. This model ensures that everyone in the family can enjoy hot showers without interruptions.

The impressive energy efficiency rating of 0.82 UEF makes it a smart choice for energy-conscious consumers. The indoor installation option allows for a clean aesthetic, and the leak detection system offers added safety and convenience.

However, some users might find the installation process a bit complex, necessitating professional help. This can increase the overall upfront costs. Additionally, while it’s capable of high output, it may be overkill for smaller homes or apartments.

• Max output: 199,900 BTUs
• Flow rate: 9.5 GPM
• Indoor installation
• Energy Factor: 0.82 UEF
• 15-year warranty on heat exchanger

Best for: Extra-large households needing maximum hot water capacity.

Rheem RTG Series 7.0 GPM Outdoor…

The Rheem RTG Series 7.0 GPM Outdoor Natural Gas Tankless Water Heater is an excellent choice for homeowners who prefer outdoor installations. Delivering 160,000 BTUs, it provides a solid 7.0 GPM flow rate, suitable for 2-3 bathrooms, ensuring ample hot water for simultaneous use.

This outdoor model eliminates the need for venting, simplifying installation and enhancing flexibility. Its durable metal cabinet is built to withstand outdoor conditions. The energy efficiency rating of 0.82 UEF helps in managing energy costs effectively.

On the downside, outdoor installations can be impacted by extreme weather conditions, and users must consider potential freeze risks in colder regions. It still requires professional installation to ensure optimal performance.

• Max output: 160,000 BTUs
• Flow rate: 7.0 GPM
• Outdoor installation
• Energy Factor: 0.82 UEF
• 15-year warranty on heat exchanger

Best for: Homeowners preferring outdoor setups.

Rheem RTG Series 8.4 GPM Indoor…

The Rheem RTG Series 8.4 GPM Indoor Natural Gas Tankless Water Heater is a reliable option for families needing consistent hot water indoors. With an output of 180,000 BTUs and a flow rate of 8.4 GPM, it efficiently meets the demands of larger households.

This model’s indoor installation is compact, allowing for efficient space usage, while its advanced safety features provide an additional layer of protection. Homeowners appreciate the precise digital temperature control panel, which allows for fine adjustments.

However, its indoor setup may require additional ventilation and could lead to higher installation costs. Additionally, the heating capacity may not be necessary for smaller homes, where a less powerful model could suffice.

• Max output: 180,000 BTUs
• Flow rate: 8.4 GPM
• Indoor installation
• Energy Factor: 0.82 UEF
• 15-year warranty on heat exchanger

Best for: Families needing consistent indoor hot water.

How We Chose These Products

We evaluated these Rheem natural gas tankless water heaters based on several criteria. Key factors included performance, energy efficiency, installation type, and customer feedback. We also considered warranty options, which play a significant role in the long-term value of these products.

Real-world usability and versatility were crucial in our selections. Each model was assessed on how well it meets the needs of different household sizes and plumbing requirements. Our goal was to ensure a well-rounded selection that addresses various consumer needs.

Buying Guide: What Really Matters

When selecting a natural gas tankless water heater, consider the flow rate, which is critical for determining how many outlets can be used simultaneously. Look for models with high BTU outputs for better performance, especially in larger homes.

Energy efficiency is another crucial factor. A higher UEF rating indicates better efficiency and lower energy bills. Installation type also matters; choose between indoor and outdoor models based on your preferences and local climate conditions. Finally, evaluate the warranty, as extended coverage indicates a manufacturer’s confidence in their product.

Frequently Asked Questions

1. How do I know which Rheem tankless water heater is right for my home? Assess your household’s hot water needs, including the number of bathrooms and simultaneous usage. This will help you determine the required flow rate and BTU output.

2. What maintenance is required for Rheem tankless water heaters? Regular maintenance includes flushing the system annually to remove mineral buildup and checking for any leaks or corrosion.

3. Can I install a Rheem tankless water heater myself? While some homeowners may attempt DIY installation, professional installation is recommended to ensure safety and proper functionality.

4. Are Rheem tankless water heaters energy efficient? Yes, Rheem models offer high energy efficiency ratings, which can save on monthly energy bills compared to traditional tank heaters.