Best Non-Condensing Tankless Water Heater 2026 Top Picks for Hot Water Comfort

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Rinnai RE140iP Non-Condensing Propane Tankless Water Heater Review

Pros:

• Energy Efficiency: One of the standout features of the Rinnai RE140iP is its energy-saving capabilities. This unit heats water only when necessary, reducing energy consumption and lowering utility bills. It’s designed to deliver hot water on demand, meaning no energy is wasted keeping water heated in a storage tank.
   
• Compact Size: Despite its powerful output, the Rinnai RE140iP is remarkably compact. At the size of a small suitcase, this tankless gas water heater can be easily installed in tight spaces, providing versatility and saving precious floor space in your home.
   
• Instant Hot Water: With a maximum flow rate of 5.3 GPM, the Rinnai RE140iP can support up to 5 fixtures running simultaneously. That’s plenty of hot water for a family shower, laundry, and kitchen needs all at once, no waiting for the tank to refill or fear of running out.
   
• Smart Features: The LED screen on the Rinnai RE140iP provides essential service reminders and error codes, helping homeowners easily keep track of maintenance needs. Plus, the option to add a Wi-Fi control module (sold separately) allows for remote management, giving you full control of your water heater from anywhere.

Cons:

• Professional Installation Required: The Rinnai RE140iP comes with a recommendation for professional installation, which could add to the initial setup costs. While this ensures the unit is properly installed, it’s something to consider for homeowners seeking a DIY installation.
   
• No Wi-Fi Control Included: While the unit supports Wi-Fi control, the module is sold separately. This can be frustrating for those expecting the convenience of smart home integration right out of the box. It’s an added expense if you want to take advantage of the remote control feature.
   
• Limited Warranty on Parts: While the Rinnai RE140iP does come with a solid 15-year guarantee on the heat exchanger, the warranty on parts and labor is only for one year. This could be a concern for those who are looking for long-term, extensive coverage.
   
• Not Ideal for Larger Households: While 5.3 GPM is sufficient for moderate use, larger households with higher water demand may find this unit lacking in performance. Multiple showers, dishwashers, and laundry machines running simultaneously could push the limits of this model.

This non-condensing tankless water heater is designed to deliver the convenience of instant hot water without the bulk of a traditional water tank. With its compact size, smart design, and energy-efficient operation, the Rinnai RE140iP is a solid choice for those looking to upgrade their home’s water heating system. However, the installation requirements and additional costs for Wi-Fi integration might be drawbacks for some users.

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Rinnai RE180iP Non-Condensing Propane Tankless Water Heater Review

Pros:

• Impressive Flow Rate: With an 8.5 GPM capacity, the Rinnai RE180iP is built for large households or spaces with high hot water demands. It can handle up to 7 fixtures running at once, making it a powerhouse for homes that need continuous, on-demand hot water for multiple showers, laundry, and kitchen use simultaneously. This is ideal for larger families or those with multiple bathrooms.
   
• Energy Efficient: Thanks to its non-condensing design, the Rinnai RE180iP only heats water when needed. This on-demand heating mechanism conserves energy, providing hot water without wasting energy on heating water that's not in use. The smart design ensures that you won’t be paying for wasted energy, ultimately reducing utility bills.
   
• Compact and Space-Saving: The Rinnai RE180iP is roughly the size of a small suitcase, which is perfect for homes that lack space for bulky water heaters. It can fit into tight spots, freeing up more room in your utility areas while still delivering robust performance. Its compact size also means it’s easy to install, though professional installation is still recommended for optimal performance.
   
• Smart Features for Convenience: Equipped with a built-in LED screen, the Rinnai RE180iP offers users service reminders and error codes to help with easy maintenance. The ability to add a Controlr Wi-Fi module (sold separately) gives you remote control, which means you can adjust settings or check the system's status from the comfort of your smartphone, perfect for those who prefer smart home integration.

Cons:

• Professional Installation Needed: While the Rinnai RE180iP boasts easy installation due to its compact design, the manufacturer recommends hiring a professional technician to ensure proper installation. This adds an additional cost to the overall purchase, as homeowners must find a qualified professional through Rinnai’s service locator tool.
   
• Wi-Fi Module Not Included: Although this model is compatible with Wi-Fi control, the Controlr module is sold separately. For those who are looking to have full smart home control out of the box, this extra expense may be frustrating. It would have been more convenient if the module was included, especially given the premium nature of the unit.
   
• Limited Warranty on Parts: The Rinnai RE180iP comes with a solid 15-year guarantee on the heat exchanger, but the warranty on parts and labor is only 1 year. For consumers looking for long-term coverage, this could be a drawback, as you might need to pay out of pocket for repairs or part replacements after the first year.
   
• Not Ideal for Extremely Large Households: While the 8.5 GPM flow rate is impressive, some extra-large households may still find themselves pushing the limits when multiple high-demand fixtures are in use. For example, simultaneous hot water needs from multiple showers, dishwashers, and washing machines could challenge the capacity, especially if the water temperature drops significantly.

The Rinnai RE180iP stands out with its high flow rate, energy-efficient design, and compact size, offering solid value for larger households or homes with high hot water demand. It’s a top choice for those seeking a space-saving, on-demand water heater with smart features for easy control. However, the professional installation requirement and additional costs for Wi-Fi control might be a dealbreaker for some.

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Rinnai RL75IN Tankless Hot Water Heater Review

Pros:

• Compact and Space-Saving: Despite its powerful 7.5 GPM flow rate, the Rinnai RL75IN is as compact as a small suitcase, making it ideal for homes with limited space. Whether you have a tiny apartment, a compact utility room, or a tight crawlspace, this non-condensing gas water heater can easily be tucked away, providing all the benefits of a high-performance tankless heater without taking up precious floor space.
   
• On-Demand Hot Water: The Rinnai RL75IN ensures you’ll never run out of hot water, even during peak usage times. With 7.5 GPM, it can comfortably supply up to 5 fixtures at once, making it perfect for larger households or multi-bathroom homes. Whether you're running showers, a dishwasher, and laundry simultaneously, this unit has the capacity to handle it all without a drop in performance.
   
• Circ-Logic Technology for Efficiency: What sets the Rinnai RL75IN apart is its Circ-Logic technology, which tailors the water heater’s recirculation patterns to your usage habits. This means it optimizes energy usage, ensuring that you're never wasting hot water. Whether you’re running a shower or filling a tub, this intuitive technology adapts, cutting down on water waste and increasing overall efficiency.
   
• Reliability and Warranty: With a 12-year guarantee on the heat exchanger, a 5-year labor warranty, and a 1-year parts warranty, the Rinnai RL75IN offers robust protection for your investment. These warranties are well above the industry standard and provide peace of mind, ensuring you're covered for years to come.

Cons:

• Professional Installation Required: The Rinnai RL75IN recommends professional installation, which could add to your upfront costs. While the design is easy to install for professionals, you’ll need to factor in the price of a certified technician, as DIY installation is not advised for this unit. If you’re looking for a more straightforward, DIY-friendly option, this may not be the best fit.
   
• Wi-Fi Control Sold Separately: While the Rinnai RL75IN is compatible with the Controlr Wi-Fi module, this module is sold separately. For homeowners who are hoping for an out-of-the-box smart-home experience, this extra purchase might be disappointing. It would have been more convenient if Wi-Fi control came as a standard feature, considering the advanced capabilities of this water heater.
   
• Limited Commercial Warranty: While the residential warranty is generous, the commercial warranty for the Rinnai RL75IN is limited to 5 years for the heat exchanger, 5 years for labor, and 1 year for parts. This shorter commercial warranty might be a concern for business owners who are looking for long-term, reliable service for commercial-grade operations.
   
• Not Ideal for Extra-Large Households: Although the 7.5 GPM is sufficient for most large households, if you have a particularly high demand for hot water, such as running multiple showers and a washing machine or spa at the same time, you may need a more powerful unit. This water heater is best suited for homes with moderate to high demand but might struggle in extreme usage scenarios.

The Rinnai RL75IN Tankless Hot Water Heater is a strong contender in the world of non-condensing tankless water heaters. Its compact design, Circ-Logic technology, and impressive warranty make it a great choice for homeowners seeking reliable, on-demand hot water. However, the need for professional installation and the extra cost of the Controlr module may be deterrents for some. Still, for the right user, this water heater offers a blend of efficiency, reliability, and performance that’s tough to beat.

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Rinnai RE199iN Non-Condensing Natural Gas Tankless Water Heater Review

Pros:

• Exceptional Flow Rate: One of the major benefits of the Rinnai RE199iN is its 9.8 GPM capacity, which provides ample hot water for multiple fixtures simultaneously. Whether you have a large family or regularly entertain guests, this water heater ensures you’ll never run out of hot water. It can easily handle 6 fixtures at once, so you can run multiple showers, a dishwasher, and laundry all at the same time without sacrificing water pressure or temperature.
   
• Compact and Space-Saving Design: The Rinnai RE199iN is surprisingly compact, about the size of a small suitcase, which makes it perfect for homes with limited space. Despite its small footprint, this water heater delivers high performance, offering flexibility in where you install it. Its size allows you to save valuable space in your utility room or closet while enjoying the benefits of a high-output tankless water heater.
   
• Energy Efficiency and Smart Technology: The Rinnai RE199iN employs advanced smart technology that only heats water when it’s needed. This non-condensing design minimizes energy waste and helps you save on utility bills. It also features an LED screen that provides service reminders and displays error codes, making it easier to troubleshoot any issues. For those looking for the ultimate in convenience, the Controlr Wi-Fi module (sold separately) enables you to monitor and control your water heater remotely, providing greater flexibility.
   
• Long Warranty and Reliable Durability: This unit comes with a 15-year warranty on the heat exchanger, 5 years on labor, and 1 year on parts, offering robust protection for your investment. With this long warranty, the Rinnai RE199iN is designed for the long haul, ensuring reliable performance and reducing your risk of costly repairs down the line.
   

Cons:

• Professional Installation Required: While the Rinnai RE199iN is easy to use and maintain, professional installation is recommended. This may add additional costs to the upfront price, as it’s crucial to have the unit installed by a qualified technician to ensure proper functioning. For those looking for a DIY-friendly unit, this could be a downside.
   
• Wi-Fi Control Sold Separately: While the Rinnai RE199iN is compatible with the Controlr Wi-Fi module, this module is not included and must be purchased separately. Many customers expect smart features to be included with the initial purchase, and the extra cost of adding the Wi-Fi functionality can be frustrating for those who want the convenience of remote control right out of the box.
   
• Limited Warranty on Parts: Although the Rinnai RE199iN comes with a 15-year heat exchanger warranty, the parts and labor warranty is only valid for 1 year. This could be a drawback for users looking for long-term coverage, especially for those who want peace of mind for more than just the heat exchanger.
   
• Not Ideal for Extra-Large Households with Extreme Hot Water Demand: While 9.8 GPM is impressive, extra-large households or homes with particularly high simultaneous water demand may find this unit lacking. If you're constantly running multiple high-demand fixtures like several showers, dishwashers, and washing machines simultaneously, you might need a model with a higher flow rate to keep up with your needs.

The Rinnai RE199iN stands out with its impressive flow rate, compact design, and energy-efficient technology. It’s perfect for medium to large households that need reliable, on-demand hot water without taking up too much space. However, the need for professional installation and the additional cost of Wi-Fi functionality might be a consideration for some. Still, for users seeking a durable, high-performance, non-condensing tankless water heater, the Rinnai RE199iN offers excellent value and reliability.

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Rinnai RE180iN Non-Condensing Natural Gas Tankless Water Heater Review

Pros:

• Space-Saving Compact Design: The Rinnai RE180iN is a compact yet powerful tankless water heater that easily fits into tight spaces. It’s roughly the size of a small suitcase, making it ideal for homes with limited installation areas. Despite its small footprint, this unit delivers an impressive 6.9 GPM output, providing hot water for up to 5 fixtures at once, perfect for larger homes or families with high hot water demands.
   
• Energy Efficiency: One of the standout features of this non-condensing water heater is its energy-saving design. The Rinnai RE180iN heats water only when it’s needed, reducing energy consumption compared to traditional storage water heaters. The smart technology ensures that no energy is wasted, helping homeowners keep their electricity bills in check. The cleaner internal layout also speeds up installation and enhances serviceability, making it easier to maintain over time.
   
• Reliable Performance with Warranty: The Rinnai RE180iN is built for durability. It comes with a 15-year warranty on the heat exchanger, 5 years on labor, and 1 year on parts, offering solid protection for your investment. This robust warranty is a testament to the reliability and long-lasting performance of this water heater, giving users confidence in their purchase.
   
• Smart Features: Equipped with an LED screen that provides service reminders and displays error codes, the Rinnai RE180iN ensures that maintenance and troubleshooting are easy to handle. Additionally, you can upgrade to the Controlr Wi-Fi module (sold separately) to remotely monitor and control your water heater. This feature adds a layer of convenience for tech-savvy homeowners looking for smarter ways to manage their appliances.
   

Cons:

• Professional Installation Required: While the Rinnai RE180iN is designed for easy installation, professional installation is strongly recommended. This might add to the initial costs as you’ll need to hire a certified technician to ensure the system is set up correctly. For those looking for a DIY-friendly solution, this could be a drawback.
   
• Wi-Fi Control Not Included: Although the Rinnai RE180iN is compatible with the Controlr Wi-Fi module, it’s sold separately. For homeowners who were hoping to have smart home integration right out of the box, this could feel like an inconvenience. Adding the Wi-Fi control module means an additional expense and effort to fully unlock the smart features of this water heater.
   
• Limited Parts Warranty: While the heat exchanger is covered for an impressive 15 years, the parts warranty is only 1 year. This could be a concern for some, especially if you’re looking for extensive coverage over a longer period of time. After the first year, you might find yourself covering costs for repairs or part replacements out of pocket.
   
• Not Ideal for Extremely Large Households: While the 6.9 GPM output is sufficient for many homes, extremely large households with multiple high-demand fixtures running at once may push the limits of this unit. For example, if you have a large family and frequently run multiple showers, dishwashers, and laundry machines at the same time, you might want to consider a model with a higher flow rate.

The Rinnai RE180iN offers a solid combination of space-saving design, energy efficiency, and reliable performance, making it an excellent choice for medium-sized homes. The 6.9 GPM flow rate is perfect for moderate to high usage, while the smart technology and robust warranty add extra value. However, the need for professional installation and the extra cost for Wi-Fi control may be a drawback for some. If you’re looking for a durable and efficient non-condensing tankless water heater, the Rinnai RE180iN checks all the boxes.