Rinnai Tankless Water Heater Reviews: 2019 Guide

When you are in need of a water heater replacement, looking for the right model for your home can be a real chore. No doubt you have heard of Rinnai tankless water heaters, and probably for good reason.

With extremely comprehensive and plentiful warranties and entirely replaceable parts, Rinnai is known for its longevity and durability. Its products display exceptional energy efficiency, while the rigorous testing ensures that all customers receive top quality products. If you’re wondering whether Rinnai tankless water heaters are the ones for you, take a look at this quick guide to the brand.

The Best of Rinnai Tankless

Rinnai Tankless heaters are dedicated to ensuring that their customers have the most comfortable experience. From compact models to quick-to-heat water, their products are designed to give a consistent performance that keeps their customers satisfied. Here are some of the things that give Rinnai Tankless such a great reputation:

Space Efficient 

Space can be valuable, especially if you live in an apartment or a smaller house. In this respect, you need a water heater that isn’t going to significantly reduce your living space. Rinnai Tankless water heaters are designed as compact wall-mounted devices that take as minimal room as possible.

Not much bigger than a small suitcase, their wall-mounted tankless heaters can be installed both on the exterior and interior walls. Not only that, the smaller size means that water heaters can be installed in more creative places to save space, such as crawl spaces and small attics. This also means it can be installed in modular homes.

Replaceable Parts

Durability is key to ensuring the longevity of your water heater. However, this means the water heater is only as durable as its weakest part. With most water heater manufacturers, when a part breaks, you need to replace the whole water heater with a new model.

Rinnai boasts that its water heaters have replaceable parts that are easy to reinstall. This means that if a component breaks, you don’t have to spend a huge amount of money replacing the water heater. Instead, with replaceable parts straight from Rinnai, you are able to extend the lifetime of your water heater at a low cost. It’s great to know that every single part of a Rinnai water heater can be replaced by the company.


With a keen eye on the environment, Rinnai recognizes that customers want products that are kind to the Earth. By increasing energy efficiency and reducing emissions, Rinnai provides products that stick with this eco-friendly testament.

This is why you will see many of Rinnai’s products displaying the Energy Star seal. This gives Rinnai the merit for producing devices that far surpass the industry standards for energy efficiency. In fact, some of Rinnai’s products have outstanding energy efficient ratings of up to 93%, meaning only 7% of energy is lost. According to Rinnai, their products can reduce energy consumption levels by up to 40% while all reducing carbon dioxide emissions. In terms of eco-friendliness, this helps to reduce your carbon footprint noticeably.

Transitioned to UEF 

Last year EF (energy factor) ratings were replaced with the new industry standard for energy efficiency measurements. The new ratings, UEF (universal energy factor) was expected to be adopted by all companies within the industry. Many brands have fallen short of this switchover, but Rinnai has taken the bull by the horns and jumped straight into this new measurement.

Where the EF only previously measured the fuel to heat efficiency rate, the UEF measurement now takes into account others factors and is better positioned to help consumers with selecting correct products based on how they use their hot water supply. While Rinnai’s products haven’t changed, they have taken the plunge to alter their ratings to this new measurement, showing their willingness to be ahead of the curve.

Recirculating Feature: Get Hot Water Quickly 

Rinnai promises its customers that they no longer have to wait for hot water when they want to shower, as their products deliver immediate hot water all over the house. Using a recirculation system to push the water through your plumbing system, hot water becomes available wherever it is needed, without delay.

Due to their dedicated return line installation, the pump pushes the water around the recirculation system through this line and straight back to the heater. Due to this, Rinnai’s solutions can be installed with any plumbing configuration system already existing in your house. Normally, those households without a dedicated return line find that adding one is a very expensive endeavor. Rinnai, however, solved this issue with the recirculation system, allowing rapid hot water without a dedicated return line.    

Quality Control Checks During Assembly

With a focus on technological quality and durability, Rinnai ensures that all products are of the best manufacturing level before they are sent out. Designed and engineered with intense precision, Rinnai products are put under extreme stress tests before being sent to the shop floor for consumer purchase.

Rinnai actually puts every product under five different staged quality control tests to ensure that every model is manufactured and assembled correctly so that Rinnai only sends out their highest standard products. On top of this, they have CSA-accredited laboratory technicians who give the products further testing for certification, development, application, and reliability. One of their two labs is dedicated to energy efficiency testing, while the other puts the products through their paces at commercial-grade application testing. All products meet an array of strict standards, including those set by the American National Standards Institute (AMNI).

Impressive Product Warranty Coverage 

Rinnai has such a high level of confidence in every one of its products that it offers an outstanding warranty. The warranty is actually the best one available from any tankless water heater manufacturer. The warranty lasts for 12 years on the heat exchanger, 5 years on parts, and one year on labor. Not only that, if your device is registered within 30 days of purchasing the unit, you can register for extended coverage on labor.

When you consider the fact that all parts can be replaced, coupled with this lavish warranty, this really gives Rinnai the top spot for the longevity of products.


While Rinnai certainly looks to go the extra mile for their customers to receive great service, this comes at a price. Rinnai water heaters are quite expensive in comparison to their competitors’ equivalent models. Not only are the upfront costs of the water heaters expensive, but they are also very hard to install. This means that you need a professional installer, and the installation costs are also pricey, resulting in quite a significant finishing total.

Some customers also complained of limescale build up inside their Rinnai products. The LC code that indicates the presence of calcium was constantly on which demands the tank be serviced and cleaned. For the inexperienced user, this may add an extra cost to have someone come out, and deal with the buildup.

Available Rinnai Tankless Water Heater Models 

Rinnai Tankless models are categorized by efficiency, labeled as High Efficiency, High-Efficiency Plus, Super High Efficiency, and Super High-Efficiency Plus. The V model catalog is their high-efficiency range, with a gallon per minute values ranging from 5.3 - 9.5 GPM on the varying models. The models, which come as either propane or gas-fuelled, have a UEF of around 0.81 and are wifi capable.

The RL and RLX models are the high-efficiency plus run. They are recirculation and wifi enabled, and have a UEF rating of up to 0.81. The units come with GPM ratings ranging from 7.5 - 9.8 and can come as either gas or propane fuelled devices.

The RUCS and RUS range is categorized as super high-efficiency, with UEF ratings of up to 0.90. It gives these models the Energy Star seal. They are wifi enabled and come with a GPM rating of between 6.5 and 7.5 gallons per minute.

The super high-efficiency category is comprised of the RUR, RUC, and RU models. These have UEF ratings of up to 0.93 and are all Energy Star recognized. They are all recirculation enabled, with RUR models having a 360 recirculation pump. Available as both natural gas and propane models, these units come with gallons per minute values of between 9.8 and 11 GPM.

Top Models in the Market

Rinnai V65IN 6.6 GPM Indoor Low NOx Tankless Natural Gas Water Heater

A natural gas powered water heater, the V65iN is installed inside and is 1.2” gas line compatible. It is wifi enabled and comes with a 10-year residential heat exchanger warranty, a 5-year warranty on parts, and a year’s warranty on labor.

Designed for a family home, this model produces 6.5 gallons per minute of hot water, making it a good model for the standard household single-family application. It has a BTU input of up 150,000 BTU and has anti-frost protection.

This model is quite energy efficient, with a UEF rating of 0.81, and an Energy Star seal which certifies this rating. It also has low NOx emissions and carbon emission, making it a safer and more eco-friendly model.

This unit comes with leak detection that will turn off the water if it suspects problems, which can prevent a great deal of property damage.

Rinnai V65EP 6.6 GPM Outdoor Low NOx Tankless Propane Water Heater

The V65EP model is fuelled by propane and is installed outside. It is also ½” gas inch line compatible and is wifi-enabled. This model has the same warranty as above with 10 years for the heat exchanger, 5 years for parts, and 1 year for labor.  It has a 150,000 BTU maximum and heats water instantly, providing 6.5 gallons per minute.

A little less energy efficient than the above model, this water heater has an energy efficiency rating of 0.79 UEF. The temperature lock prevents accidental alterations on the temperature, which helps to increase energy efficiency when in use.

Regarding durability, this model has enhanced scale detection, censoring the buildup of limescale and helping users to troubleshoot this issue. It helps to keep the unit maintained, and prevents blockages and drops in efficiency.

Rinnai RUC98iN Ultra Series Natural Gas Tankless Water Heater

More suitable for larger applications, this natural gas-powered model can generate up to 9.8 gallons of hot water per minute. Extremely compact in size, this model can be installed inside in a little hideaway and has both a concentric of PVC venting option. The warranty on this model lasts for 12 years on the heat exchanger, 5 years on the parts, and a year on labor. This model is also wifi enabled and has a maximum BTU output of 199,000.

With a UEF factor of 0.92, this model is outstandingly efficient and also, therefore, heralds the Energy Star compliant seal. As well as its efficiency in fuel consumption, this unit has ultra-low NOx and carbon emissions, which significantly reduces your carbon footprint, showcasing this model as an eco-friendly device.

Tankless Water Heaters vs. Hot Water Tanks

Conventional water heaters come with big tanks that are known to be reliable. Installers and plumbers are more than familiar with how these systems work, and therefore have a sense of trust in a system that they know as straightforward. Due to this, the upfront costs of these kinds of water heaters and the installation costs tend to be relatively inexpensive, in comparison to tankless water heaters. In fact, many people can install them by themselves. Often argued to be inefficient in terms of energy consumption, technology has improved to the point that there are now Energy Star rated conventional water heaters.

However, on the flipside, conventional tank water heaters are always on, meaning that despite their energy efficiency rating, they will always be using energy to keep the water hot, whether needed or not. Equally, their big, bulky size is inconvenient in small spaces and often produces far too much hot water for the average family. Moreover, many people tend to inherit the space for a tank from the previous owners. This means they are limited to the capacity they can have, meaning they may not be able to meet their demand if they cannot fit a big enough tank in.

The big, bulky tanks also mean that installation is less versatile, as the tanks cannot be hidden so easily in smaller spaces. And as it cannot be placed outside the home, there has to be an area dedicated to it.

Tankless water heaters, in contrast, only work when someone needs hot water, heating the water on demand. This can reduce energy costs by around 25% or more per year. While only heating water on demand increases the energy efficiency of tankless water heaters, the models are far more energy efficient by their operational design than tank versions. Some tankless units can have UEF values as high as 0.93 compared to an efficient tank water heater with a UEF of 0.65.

Being small in size allows for more options when it comes to the installation of tankless water heaters. Despite their small size, if correctly fitted, tankless models will generate continuous instantaneous hot water all around the house to meet your demands. You will also find that the long warranties on tankless water heaters demonstrate the durability of the products, with some lasting up to 20 years.

However, tankless models are expensive to buy and have a more complicated installation. This means you often have to pay for a professional to put it in. It is not easy to retrofit a tankless model, and venting materials and labor can be pricey.

Rinnai Tankless Company History

Based in Nagoya, Japan, Rinnai began making products just under 100 years ago. First incorporated in 1920, Rinnai launched its first tankless water heater in 1921. The company went public in 1950 on the Tokyo Stock Exchange to expand its market. By 1967, they had consolidated their research and engineering to open a new technology center for innovation. In 1974, Rinnai established their US-based company Rinnai America Corporation, in Los Angeles.

By the early 2000s, Rinnai was improving its product range with a new tankless water heater in 2000 and a commercial version in 2001. This led to them being voted #1 as Builder Magazine's “Most Popular Product” for their LS Series Tankless Water Heaters in 2006.

In 2009, Rinnai narrowed down their focus to efficiency, and 6 products earned the Energy Star, with condensing tankless models being presented the following year.

Rinnai now has 20 branches around the world. Six of these branches are in Japan, with 86 sales offices across 15 countries, including Thailand, the UK, Vietnam, and the USA.


Rinnai is an undoubtedly solid brand to put your confidence in when choosing a water heater. Make sure you understand your requirements when choosing a water heater for your household. A reliable and durable brand with an excellent warranty and a dedication to longevity, Rinnai products are a great choice. Just remember that upfront costs and installation can be a little pricey.

Enter your text here...

Leave a Comment