Buying guide for best Rinnai tankless water heater models
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A tankless water heater could make you a happier homeowner by reducing your energy bill. If you are unfamiliar, these innovative appliances deliver hot water on demand. This way, you don’t have to heat up a large tank full of water and store it until you need it. Instead, you heat the water only when you are ready to use it, which saves energy.
One of the top brands that makes these is Rinnai, a Japanese company that’s been around for more than a hundred years and now manufactures tankless water heaters in Griffin, Georgia. The best Rinnai tankless water heater models will supply you with sufficient water flow for your needs while offering efficient, safe and convenient performance.
As desirable as these items are, it’s important to understand they do have some limitations. The upfront cost is higher than a tank-based system, the water flow rate may be lower than you are accustomed to (especially if you are switching over from a tank), high-demand situations, such as large families, are not ideal, and extreme low temperatures can negatively impact its performance.
Fortunately, there are intelligent workarounds, such as using more than one tankless system for high-demand situations, which make a tankless system a better option for many homes. We love the Rinnai RX199iN Condensing Smart Sense Tankless Water Heater for its high flow rate, versatility and money-saving tech, but there are other terrific models from Rinnai, which we’ll delve into here, that may suit your needs better.
Which Rinnai tankless water heater model is best?
Rinnai RX199iN Condensing Smart Sense Tankless Water Heater
Best of the Best
Flow Rate: 11.1 GPM | Fuel Type: Natural Gas or Propane | Energy Efficiency: EF 0.98 | Btu Range: 199,000 Btu | Temperature Range: 140 degrees (maximum)
The Rinnai RX199iN is an extremely versatile tankless water heater. It features a Versa Vent, so the model can be installed either indoors or outdoors, depending on your needs.
It also can accommodate either propane or natural gas. And thanks to the Smart Sense fuel-control system, the appliance automatically knows which fuel type you are using.
Despite its compact size, this impressive unit can deliver up to 11.1 GPM. It has a user-friendly interface and the highest energy-efficiency factor of all the models on our short list: 0.98. We also love the Quick Flush technology, which adds convenience to the maintenance process.
Rinnai's RX199iN condensing tankless water heater has all the features you crave and the power you need. Because of its performance and flexibility, we've rated it the Best of the Best. If you want the top-tier option, this is it.
Rinnai RX130iN Condensing Smart Sense Tankless Water Heater
Best Bang for the Buck
Flow Rate: 7.1 GPM | Fuel Type: Natural Gas or Propane | Energy Efficiency: EF 0.97 | Btu Range: 130,000 Btu | Temperature Range: 140 degrees (maximum)
The Rinnai RX130iN is the little brother of the Rinnai RX199iN. It offers many of the same features, such as the Versa Vent and the Smart Sense fuel control system. This means the RX130iN can be installed indoors or out using either propane or natural gas. It also has the ability to capture and recycle heat to keep the unit's EF rating high.
This model is only about the size of a small suitcase, but it still can provide hot water for up to four fixtures at once, making it suitable for a family of four. This Rinnai also has an intuitive interface with a Quick Flush feature, and a Wi-Fi control can be added, if desired (Control-R sold separately).
The best part of this offering is that it’s gentle on your budget. You can get all of these features and high-tech performance for a little over $1,000, making it our choice for great value.
Rinnai REP160iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater
Best Indoor Natural Gas
Flow Rate: 6.1 GPM | Fuel Type: Natural Gas | Energy Efficiency: NA | Btu Range: 160,000 Btu | Temperature Range: NA
If you prefer a natural gas model, the Rinnai REP160iN has Smart-Circ technology that adds effortless convenience and comfort to your life.
The technology learns when you use hot water and automatically schedules the system for recirculation, so you always have plenty of hot water when you need it most.
The compact design makes installation possible in a wide variety of spaces, and this model comes with a 15-year guarantee for the heat exchanger to give you peace of mind for over a decade.
Also, like other Rinnai tankless water heaters, you can purchase Wi-Fi control for added convenience. Thanks to all of these features, the Rinnai REP160iN is our pick for the best indoor natural gas tankless water heater.
Rinnai V53DeP Propane Tankless Hot Water Heater
Best for Small Homes
Flow Rate: 5.3 GPM | Fuel Type: Natural Gas | Energy Efficiency: EF 0.82 | Btu Range: 273,000 Btu | Temperature Range: 120 degrees (maximum)
Not every home needs a high-end tankless water heater system outfitted with an abundance of bells and whistles. If you are looking for a basic model that just does what it is supposed to do — warms up your water to a comfortable temperature for your daily needs — you will find the Rinnai V53DeP Propane Tankless Hot Water Heater is a good option.
With a 5.3 GPM flow rate, this model is best for smaller homes or smaller families. It features a rugged design, so it can withstand exposure to the elements and still provide the warm water your home needs.
The thoughtful inclusion of enhanced scale detection reduces the possibility of serious long-term damage that may arise from mineral deposits forming inside your system.
We recommend this compact model for smaller homes and people who need to stick to a strict budget but are unwilling to sacrifice quality.
Rinnai REP199iP Smart-Circ Non-Condensing Propane Tankless Water Heater
Most Reliable Hot Water
Flow Rate: 7.9 GPM | Fuel Type: Propane | Energy Efficiency: NA | Btu Range: 199,000 Btu | Temperature Range: NA
The Rinnai REP199iP is an indoor propane tankless water heater. It has a built-in recirculation pump controlled by the company's Smart-Circ technology. This means your water heater learns your usage patterns, so it knows when you need hot water. The unit schedules hot-water recirculation appropriately for maximum energy efficiency and convenience.
With a flow rate of 7.9 GPM, this model can service up to six fixtures at once, making it a good option for the average family. The compact design means you can install the unit indoors, even if you don't have a lot of room.
Combining the top-performing fuel type with Smart-Circ technology and Rinnai's trusted brand name created just the right alchemy to make this our choice for the most reliable hot water delivery.
How we analyzed the best Rinnai tankless water heater models
BestReviews is adept at navigating the market to find the top products for your needs. For this article, we compiled a list of features required for real-world applications and evaluated them according to consumer needs. Besides creating a hierarchy to determine which Rinnai model is the overall top choice, we scrutinized the details to determine which models are best for homeowners with different needs. To be certain our results are unbiased, we also take consumer reviews into consideration before forming our final opinion.
Key features to consider
Water heating capacity (flow rate)
Gallons per minute (GPM)
Since the water is heated on demand in a tankless water heater, how fast that hot water comes out is a key factor in determining which model is best for your usage needs. The flow rate is expressed as gallons per minute.
While it’s possible to be strategic with your hot-water usage and never schedule showers, dishwashing and laundry simultaneously, for the ultimate in convenience, a small household with one or two bathrooms typically requires a tankless water heater with a flow rate of 5 to 6 GPM. A home with two or three bathrooms would be better served with a flow rate of 7 to 8 GPM. If you have a house with more than three bathrooms and a family that may use them simultaneously, a tankless water heater with at least 9 GPM is a wise choice.
Climate considerations
If you live in a colder climate, you'll need to consider a model with a higher-than-typical flow rate. This is because a tankless water heater must work harder to raise the temperature of groundwater that comes in colder. For example, people who live in the northern region will want to consider a model with at least a 10-GPM flow rate.
Our top picks: Water heating capacity (flow rate)
- Rinnai RX199iN Condensing Smart Sense Tankless Water Heater: This model is available in 7, 9, 10 and 11 GPM versions, so you can select the best one for your needs.
- Rinnai RX130iN Condensing Smart Sense Tankless Water Heater: Like the RX199iN, this model has four different flow rates so you can choose the one that best fits your household hot-water usage needs.
- Rinnai REP160iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater: This tankless water heater is a better choice for small to medium homes as it maxes out at 7.9 GPM.
- Rinnai V53DeP Propane Tankless Hot Water Heater: The V53DeP is only available in 5.3, 6.5 and 7.5 GPM options, so it’s better suited for low-usage homes in warmer climates.
- Rinnai REP199iP Smart-Circ Non-Condensing Propane Tankless Water Heater: This model ranges from 5.3 to 7.9 GPM, making it better for small to medium homes with up to two and a half bathrooms.
Fuel type
Natural gas
A natural gas water heater lasts longer than an electric model. It also heats faster, has lower operating costs and is better suited for homes that have a high demand for hot water. On the downside, these models are more expensive and require a natural gas connection along with higher installation costs.
Propane
Like natural gas models, propane models last longer, heat faster and have lower operating costs. Propane is also more energy efficient than natural gas — it can produce roughly twice the heat as the same amount of natural gas. This means propane costs more but offers better bang for your buck, and it’s suitable for rural homes and off-grid living.
Electric
A Rinnai electric tankless water heater is more compact than a natural gas model. It’s also not as expensive to install. Unfortunately, an electric model doesn't heat the water as quickly and costs more to operate. Additionally, an electric model has a shorter lifespan — closer to a tank-based water heater system.
Our top picks: Fuel type
- Rinnai RX199iN Condensing Smart Sense Tankless Water Heater: The RX199iN can be installed using natural gas or propane fuel, making it a highly desirable option.
- Rinnai RX130iN Condensing Smart Sense Tankless Water Heater: If you want longevity, convenience and versatility at a great value, this model is the way to go.
- Rinnai REP160iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater: This natural gas tankless water heater features indoor installation, high Btu and long life.
- Rinnai V53DeP Propane Tankless Hot Water Heater: The V53DeP is a propane tankless water heater that is only rated for outdoor installations.
- Rinnai REP199iP Smart-Circ Non-Condensing Propane Tankless Water Heater: If you are looking to go off the grid or have a rural home, this highly efficient propane model is a solid option.
Energy efficiency
Energy factor (EF)
The Energy Factor of a tankless water heater tells you how efficient the model is. It’s a number based on the ratio of how much hot water is produced compared to how much fuel is consumed. The higher a tankless water heater's EF is, the more energy efficient it is. For example, a tankless water heater with a 0.92 rating is 92% energy efficient. In general, tankless water heaters are extremely energy efficient, with most having an EF of at least 0.80.
Condensing vs. non-condensing model
There are two main types of tankless water heaters: condensing and non-condensing. A condensing model captures and recycles heat from the exhaust to increase a model's EF rating. Typically, these models range from an EF of 0.85 to an EF of 0.96. A non-condensing model, by comparison, usually has an EF of 0.80 to 0.82. The condensing models cost slightly more but can save you more money over time.
Our top picks: Energy efficiency
- Rinnai RX199iN Condensing Smart Sense Tankless Water Heater: The RX199iN has an energy factor of 0.98, which means there is only 2% waste.
- Rinnai RX130iN Condensing Smart Sense Tankless Water Heater: This condensing tankless water heater also comes in with a remarkably high rating of 0.97.
- Rinnai REP160iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater: The manufacturer doesn't publish the actual EF on this non-condensing model, but it does label it as "high efficiency."
- Rinnai V53DeP Propane Tankless Hot Water Heater: Being a non-condensing unit, this Rinnai tankless water heater has a lower energy factor. It’s only 0.82, which still outperforms many traditional tank-based water heaters.
- Rinnai REP199iP Smart-Circ Non-Condensing Propane Tankless Water Heater: The manufacturer hasn't noted the EF on this non-condensing unit. However, it does state that the water heater is a high-efficiency model.
Installation location
Indoor installation
Another option when purchasing a Rinnai tankless water heater is to buy an indoor or outdoor model. An indoor model can be mounted on the wall in homes with the space and flexibility for plumbing adjustments. This type is best in colder climates, and it usually does not require as much maintenance because it’s not exposed to the elements. However, you do need adequate ventilation to protect against carbon monoxide buildup in combustible units.
Outdoor installation
An outdoor tankless water heater is best for warmer climates where there is little to no concern of pipes freezing. This type is also good for people who have limited indoor space. If you choose an outdoor model, you won't have to worry about ventilation, and installation may be easier.
Our top picks: Installation location
- Rinnai RX199iN Condensing Smart Sense Tankless Water Heater: Our "Best of the Best" pick can be installed indoors or outdoors, giving the consumer maximum flexibility.
- Rinnai RX130iN Condensing Smart Sense Tankless Water Heater: The Rinnai RX130iN also features the convenience of either indoor or outdoor installation, giving the consumer the ability to install it in any location.
- Rinnai REP160iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater: This model must be installed indoors, making it a good option for homeowners with ample indoor space.
- Rinnai V53DeP Propane Tankless Hot Water Heater: If you have limited indoor space, the V53DeP is a solid option because it features outdoor installation.
- Rinnai REP199iP Smart-Circ Non-Condensing Propane Tankless Water Heater: For individuals who live in a colder climate, this compact model is ideal because it features indoor installation.
Water heater technology features
Recirculation technology
Rinnai has an option that lets you recirculate water that has already been heated, giving you the hot water you demand even faster. And the best part is select models have a thermal bypass valve that lets you recirculate hot water even if your system does not have a dedicated return line.
Wi-Fi connectivity
The most common uses of a smart appliance are remote control and scheduling from any place you can connect to the internet. Another tech bonus from Rinnai is to help monitor usage, offer diagnostics and make maintenance hassle-free.
Temperature control
Rinnai's advanced temperature control technology monitors temperature and adjusts flow rate so the user always has the precise temperature they desire.
Self-diagnostics and maintenance alerts
Rinnai offers self-diagnostic capabilities to help make your water heater as easy to operate as possible. Whenever a problem arises, the system displays error codes on the control panel, so you know exactly what is happening. If you missed (or forgot) a code, no worries. You can cycle through error and maintenance codes to ensure you never miss a single alert.
Our top picks: Water heater technology features
- Rinnai RX199iN Condensing Smart Sense Tankless Water Heater: Besides Wi-Fi control (sold separately) and an energy-efficient design, this model knows what fuel you are using and has quick flush technology for convenience.
- Rinnai RX130iN Condensing Smart Sense Tankless Water Heater: For convenience, the RX130iN features remote operation (sold separately), quick flush and intelligent sensors that automatically detect what type of fuel you are using.
- Rinnai REP160iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater: This model contains new technology that learns your usage patterns and schedules recirculation to ensure you always have hot water when you want it.
- Rinnai V53DeP Propane Tankless Hot Water Heater: Besides recirculation technology, the V53DeP has advanced scale detection to help prevent damage from mineral buildup and keep your appliance running better for longer.
- Rinnai REP199iP Smart-Circ Non-Condensing Propane Tankless Water Heater: This model also features Rinnai's Smart-Circ technology that ensures hot water is always ready when needed.
Our expertise
Before writing articles and product reviews for BestReviews, Allen Foster worked for a national home improvement chain. Besides being trained and attending product classes taught by company reps, Allen had the opportunity to compare several brands head-to-head to learn what made each stand out. It’s this real-world, hands-on knowledge that informs his writing, giving him the ability to offer valuable purchasing insights to individuals seeking to buy the best home-improvement products for their needs.
