Top 5 Best Rinnai Tankless Water Heaters

The chances are that unless you’re a plumber (or a landlord), you’ve probably never heard of Rinnai before. But if you had heard of them, you’d know that they make some of the best water heaters and boilers in the world (at an affordable price point).

You’ve probably come across this article because you’re shopping around for replacement water heaters. We guess you’ve got 1001 questions about the brand, their reputation, and most importantly – their products.

Well, you can stop looking because you’ve just found the most comprehensive guide to Rinnai and their tankless water heaters on the entire internet. Today we are going to discuss what we like (and what we don’t like) about the brand, and we’re going to review some of their most popular products.

We recommend you grab a drink and get comfy because this is going to be a long one…

Let’s get started.

Rinnai Tankless Water Heaters Comparison Chart

ModelFuelUsesFlow RateBTUCertificationPrice
Rinnai RUR98iNNatural GasIndoor9.8 GPM 199,000 Energy Star
Rinnai RUC98iNNatural GasIndoor9.8 GPM199,000 Energy Star
Rinnai RL94iPPropaneIndoor9.4 GPM199,000Energy Star
Rinnai RL75iNNatural GasIndoor7.5 GPM180,000Energy Star
Rinnai V65EPPropaneOutdoor6.6 GPM150,000-

Who Are Rinnai?

Rinnai is a Japanese company that has been in business since the 1920’s. When the company was first founded, it was in the oil stove industry, but they soon evolved into primarily dealing with water heating in the 1940’s.

They are a company that has gone from strength to strength over the years, slowly but surely building their reputation into the formidable thing it is today. They are one of the water heating industries most respected brands and are known for reliable, efficient products provided at a low cost to the consumer.

Rinnai is constantly pushing modern-day water heating technology to its limits. Their innovations have changed the game more times than we can remember. They are constantly striving to improve their products faster than the competition…

And up until now, they have continuously succeeded.


How a Rinnai Tankless Water Heater Works?


The Best Rinnai Tankless Water Heaters – Our Reviews

Ok, that’s enough about the company. Let’s take a look at some specifics. Below we are going to list some of our favorite Rinnai heaters that we know to be reliable and excellent value for money. We are going to list them in order of price (starting with the most expensive).

Rinnai RUR98iN Ultra Series Condensing Tankless Heater with Recirculation 

RUR98i is one of the biggest and best water heaters that Rinnai produce. It represents the cutting edge of modern water heater technology. This is a highly efficient product that runs on natural gas (and has an amazing GPM rate).

Special Features:

  • Maximum output, minimum space.
  • Innovative technology provides an endless supply of hot water.
  • Installation Type-​Indoor, Tankless Rack System (TRS/TRW) Compatible,1/2″ Gas Line Compatible
  • Recirculation capability, with or without a dedicated recirculation line Innovative technology provides an endless supply of hot water.
  • Offers both Concentric and PVC, providing more venting options right out of the box
  • Rinnai’s condensing technology features dual heat exchangers to provide maximum efficiency, up to .96 Energy Factor.


The Pros

The most obvious thing to like about this water heater is the massive GPM rating it provides its owner. Its 9.8GPM is one the highest on this list (and is one of the highest in the world). This is a heater that is more than capable of heating a large family home where you’re likely to be running multiple hot water hungry devices at the same time.

However, this is not a normal water heater. Normally the 9.8GPM would be a show-stopping feature, but the big thing you should be excited about here is the products recirculation feature. We won’t go into the technical details and bore you here, but basically, it means you can have an endless supply of nearly instant hot water instead of having to wait for it to circulate your pipes.

The .96 efficiency factor (96% efficient) is also something worth shouting about. This is about as efficient as residential water heaters can get. When you consider how much water this thing is going to be heating on a daily basis, a super high-efficiency rating like this is an almost essential part of the package.

The Cons

The most obvious issue with this heater is the price of the unit. It’s a big product that has taken a huge amount of time, money and resources to design and build. As such, it’s not exactly what you would call “cheap”.

But apart from the pricing, there is not much to dislike about this product. It’s a top of the cutting-edge range example of the excellence of Rinnai’s engineers and the company’s extensive experience.


This is the easiest recommendation for us on this list. As we mentioned, it’s one of the best water heaters Rinnai (or anyone else) produce. The recirculation feature is literally game changing and is a prime example of the kind of innovation that Rinnai is known for.

Recirculation is one of those things that you’ll never be able to live without once you have it. An endless supply of nearly instant hot water that increases efficiency and reduces water wastage is a beautiful thing to have in your day to day life. Despite this, it’s far from what we would deem to be an essential feature, but if you want the best – this is it.

Sure it’s not cheap, but this is a premium product that has a premium price tag. You get what you pay for when it comes to boilers, and considering the specifications and functionality this unit provides. It’s a great value for money.

Click here to Buy from Amazon

Rinnai RUC98iN Ultra Series Twin Pipe Installation 

The RUC98iN is the second most expensive water heater on our list. It’s very similar to the RUR98iN we just discussed above, but it’s around $500 cheaper. If you are in the market for something this size and liked the sound of the RUR98iN, you should certainly consider the RUC98iN too.

Special Features:

  • 199,000 max BTU
  • Concentric or PVC venting option
  • Up to .96 Energy Factor
  • Ultra low NOx emissions
  • The space-saving design allows installation almost anywhere


The Pros

Again like the RUR98in, this product has a fantastic 9.8GPM rating that’s going to be able to provide any ho water hungry home with all the water it needs. It’s quite difficult to overstate just how much water 9.8GPM is. You’d really have to try and use it all by turning every tap, shower, and machine on in the house before you started to notice a temperature drop.

Again it’s got the same energy efficiency rating as the RUR98iN too. It’s .96 efficiency factor (96% efficient) is one of the best on this list, this going to help you keep your energy bills down really.

The Cons

The most significant “con” this heater has is that it doesn’t have the recirculation feature of the RUR98iN we mentioned above. As we mentioned earlier recirculation is a great addition to any boiler, and if you have it in your home, it’s not going to be something you regret. But that being said, you can most certainly live without it if you don’t think it’s worth the extra money.


This is a boiler that Rinnai has produced to give consumers a choice. It’s pretty much the exact same boiler as the RUR98iN just without the recirculation technology. We’re reluctant to recommend one or the other here. Some people will find the $500 or so price increase for recirculation technology good value for money, and others will find it an unnecessary expense.

However, compared to other boilers on the market this product is an absolute bargain. It’s pretty much got the best specs money can buy (without going to extreme prices). Again this is not exactly a cheap product. But for long-term investments (like water heaters) it usually pays off, in the long run, to get a quality item that you’re sure will do the job properly and stand the test of time.

Click here to Buy from Amazon

Rinnai RL75iN 82% Thermal Efficiency 7.4 GPM

Now before we get into this review, it’s important to remember that the RL75iN is a much cheaper product than both the other products above. As such you have to adjust your expectations accordingly. For the price of the unit, this is a great little heater.

Special Features:

  • 10,300 – 180,000 BTU
  • 82% Thermal Efficiency
  • Residential Temperature Settings: 98°F – 140°F
  • MC-91-1US Digital Controller with Error Code Indicator


The Pros

The best thing about RL75iN is the huge 7.4 GPM that it can provide. We know that this might sound a little underwhelming after hearing about the 9.6GPM of the two heaters above. But trust us, 7.4 GPM is more than enough for most family homes, the two heaters above are almost freaks of nature in the water heater world (and should not be used as a benchmark).

7.4 GPM will be a little easier to use up than 9.6 GPM, but it’s still more than enough to satisfy a large family. You could probably use three showers and a washing machine at the same time without noticing a significant temperature drop. Any more than that and you’ll probably begin to notice a decrease.

The Cons

The most significant con of this heater compared to the two above is the energy efficiency rating. The RL75iN has a .82 rating (82% efficient). Compare this to the 96% efficiency rating of the other natural gas heaters on this list, and it’s quite a stark difference. Those percentages seem a little bit abstract, so let’s put it in real-world money terms here.

You are going to be paying 14% more for your water if you buy the RL75iN instead of the RUC98iN.

That’s not an insignificant difference.


Considering the high GPM of this unit, it’s a great deal. There are not many other products on the market at this price point that can provide this much water (but there are some). We are slightly disappointed by the efficiency rating, and it’s an essential factor that Rinnai has slightly dropped the ball on here.

In all honesty, we highly recommend that you consider spending the extra $500 or so and get the RUC98iN instead of the RL75iN. $500 is not an insignificant price increase we know, but it’s a sound investment over the long run. With this product, you’ll be paying 14% more on your energy bills for the next 10 to 15 years. That is almost certainly going to add up to more than $500 (and you’ll get more capacity out of the RUC98iN too).

But if you really can’t afford the extra $500, the RL75iN is a fine boiler that will stand the test of time and is great value (considering the price point compared to the competition).

Click here to Buy from Amazon

Rinnai RL94iP Residential & Commercial Tankless Heater

This is a great heater. We usually prefer natural gas, but if propane is what you need – then this is a product that is more than worthy of your consideration. Its GPM is lower than both products above, and it’s much less efficient – but it’s much cheaper.

Special Features:

  • 10,300 – 199,000 BTU
  • 83% Thermal Efficiency
  • MC-91-1US Digital Controller with Error Code Indicator.
  • Heavy duty forged brass Webstone Isolator service valves.
  • Residential Temperature Settings: 98°F – 140°F


The Pros

The 9.4 GPM that is provided by this heater is an amazing amount of capacity considering the price of this unit. We can’t think of many other propane based heaters from other brands that can provide this kind of performance at this price point. It’s a little less capacity than both the top of the range RUC98iN and the RUR98iN we talked about above, but to be totally honest it’s an almost negligible difference of 0.2 GPM.

The Cons

The biggest issue we have with the RL94iP is the efficiency rating it has. We were a little surprised to find out that it’s been rated at .84 (84% efficient). This is reasonably good for a propane water heater, and it’s even better than the RL75iN natural gas heater. However, we cannot in good conscience sit here and tell you that a .84 efficiency rating is good.


This product is a little tricky for us to recommend fully, but it’s more than worthy of your consideration. If you absolutely have to have a propane powered water heater, you could do a lot worse than the RL94iP.

The main thing you need to take into account here is the efficiency rating. Water heaters are a long-term investment, and the efficiency rating directly effects how much you are going to be spending on your energy bills. And as hot water is one of the biggest consumers of energy in the home, it’s going to really add up over time.

But as far as propane water heaters go, it’s not too bad at all.

Click here to Buy from Amazon

Rinnai V65EP Outdoor Propane Heater 

The final water heater we are looking at today is the only outside heater on our list. It’s a well built sturdy machine that is packed full of technology to provide your home with ample amounts of hot water at a very reasonable price.

Special Features:

  • 150,000 Max BTU
  • Energy Factor of .82 for Natural Gas and Propane
  • Certified for Installation in Manufactured (Mobile) Homes
  • Enhanced scale detection lessens possibility of serious, long-term damage to unit
  • Temperature lock prevents accidental or unauthorized changes to water temperature
  • Complies with South Coast Air Quality Management District 14 ng/J or 20 ppm NOx emission levels


The Pros

The best bit about this heater quite honestly is the price. It’s the cheapest product on this list at around $700 and is great value for money. However, as the most affordable product, it’s also the lowest rated in terms of GPM. The 6.6 GPM that the V65EP has is significantly lower than almost every other heater on this list.

So why are we listing it as a pro instead of a con?

Well, it’s because that you’re not going to be able to find a product that has this kind of GPM and this build quality anywhere else at this price point. For the price, 6.6 GPM is great value for money when you consider this is a Rinnai product.

Sure you can find other 6.6 GPM heaters on eBay for a hundred dollars or so cheaper. But they will be a no name Chinese brand that will be incomparable to a Rinnai product in terms of quality.

The Cons

To be honest, we could almost have listed the efficiency rating of the V65EP as a pro considering the price point, but it could be improved a little. The V65EP has a .82 efficiency rating (82% efficient), which for a propane heater is not too bad at all. If we were picky it would be nice to see that rating a little higher (in the .84 – .85 range) but all in all – not too shabby at all.


There’s not that much to really say about this product. It is what it is. It’s a mid-range product that is verging on being a budget model due to its low price. The efficiency rating isn’t great, but it isn’t terrible either. The GPM is decent enough for a mid-sized family home, and you can rest assured that it’s a reliable product (because Rinnai makes it).

There are better water heaters on this list (in fact all of them are better). But considering how much you are paying for the V65EP it’s an absolute bargain. There is not much on the market from other brands that can compete with this level of quality and performance at around $700.

Important Note: Natural gas is inherently more efficient than propane as an energy source. It’s unfair to compare the energy efficiency of natural gas boilers and propane boilers regarding product quality. The difference mainly comes from the fuel and not the product.

Click here to Buy from Amazon

Final Words

So there you have it, everything you ever wanted to know about Rinnai and their water heaters.

As a parting note, we just wanted to mention how important it is to invest as much as you possibly can into a water heater (and to go with a trusted brand). If you decide to skip out on the investment, you’re probably in for a bad time further down the road.

When a water heater breaks down, it’s an extremely annoying thing. Days without hot water mean plenty of cold showers in the morning (which I’m sure you already know, really sucks). You’ll be kicking yourself for going with a no-name brand when this breakdown inevitably happens.

(Plus the cost of the repairs will probably make what little saving you made on the initial purchase seem insignificant).

Additionally, you should try to get the most energy-efficient model you can afford. Even a 5% increase in efficiency will translate into much lower energy bills (and significant savings) over the long term.

Rinnai is already considered to be a highly affordable brand by plumbers and professionals in the water heater industry. There are not many other companies that can provide products with a similar specification that are going to stand the test of time.

All the products we have included in this article today are of excellent quality. It might sound like we have been a little bit critical of some of them (especially on efficiency ratings) but that’s just how we roll here.

Considering our high standards, Rinnai has done very well in this review.

Any of the products on this list are more than worthy of your consideration. Providing you pick one that has a high enough GPM rating for your requirements, we can’t possibly see how you could ever be disappointed with any of them.