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The Best Tankless Propane Water Heater for Your Modern Home

Best Overall
Best Value
Rinnai V65iP
Best Choice
Rinnai RL94IN

The first-ever tankless water heater was introduced to the world in 1889, and almost 125 years later, the demand for these superior water heaters is continually rising.

If you’ve ever wondered what’s so special about propane tankless water heaters, then you are at the right place to learn more about them. Here’s our list of tried and tested options and the best tankless propane water heater for your home!

Our Top Tankless Propane Water Heater for Modern Home Picks

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The Best Tankless Propane Water Heaters

1. Rinnai Indoor Propane Tankless Hot Water Heater

If you’re considering buying tankless water heaters for your home and company use, the Rinnai indoor propane water heater we tested is the best choice to consider.

With a maximum flow rate of 7.5 GPM and heating power of 180,000 BTU, you can comfortably connect this water heater to two or three bathrooms at the same time.

Its effective temperature settings hit a maximum of 140oF for residential settings and 1600F for commercial settings. However, you have to purchase an additional controller to achieve the super-hot temperatures of 1600F.

It’s one of the best tankless propane water heaters because it has a water heater has an efficiency rating of 0.81, measured by UEF standards. You can trust it to give you the best heating results at minimum use of gas.

Its horizontal and vertical ventilation options make it an excellent model for your indoor water heating endeavors. It can fit into a setup that perfectly works for your available space.

The water heater also gives you two fuel options to choose from. You can either fuel it using propane or natural gas. While propane is more expensive than natural gas, it is more efficient as it has double the BTU rating. It can therefore be a more efficient fuel option to choose in the long run.

It comes with two outstanding monitoring sensors, which along with others, ensure it works safely inside your house.

The first sensor is the temperature lock system that prevents accidental fluctuations in the water temperature.

The second sensor is the unique inbuilt scale detection system that shows you when there’s a buildup of scale. It is an ideal tool to check when maintenance is required and helps keep your heater working for a long time.

Compared to the Eccotemp L5 1.5 GPM Portable Liquid Propane Outdoor Tankless Water Heater, the Rinnai Indoor Propane Tankless Hot Water Heater and Eccotemp L5 1.5 GPM Portable Liquid Propane Outdoor Tankless Water Heater are two different types of water heaters with different use cases. The Rinnai is designed for indoor use and provides a high flow rate of hot water on demand, while the Eccotemp is a portable unit for outdoor use and has a lower flow rate.


2. Eccotemp L5 1.5 GPM Portable Liquid Propane Outdoor Tankless Water Heater

If you love the great outdoors but are unwilling to put up with cold showers, then Eccotemp L5 is your water heater to pick out of all of the options we tried out.

It is currently the only legal CSA-certified portable water heater legally sold in the US and Canadian markets.

It is lightweight and compact for easy portability and the ideal choice for camping, RV’s, tiny homes, poolside, greenhouses, and anywhere else out of the home where you need an endless and reliable warm water supply.

Despite having an electronic ignition powered by 2 D-cell batteries, the water heater isn’t powered electronically. It is fueled by a 20-pound liquid propane tank that you can easily carry with you to your outdoor events.

It has a flow rate of 1.5 GPM, which is just enough for basic needs and your daily outdoor needs. With a heating power of 37,500 BTU, you can be sure to get enough hot water with temperatures ranging from 50-1400F for your daily outdoor use.

Its gas regulator helps you to adjust the gas flow for your varying temperature needs easily.

With full control of water flow and heat regulations, you can conserve both water and propane. Even at the lowest flow and lowest heat controls, you can still enjoy warm water that comes out pretty fast.

Compared to the Eccotemp L5, the Rinnai is a larger unit designed for indoor use with a higher flow rate.


3. Rinnai V65iP Propane Tankless Hot Water Heater

Rinnai did an excellent job with this powerful V65iP tankless heater. It features a powerful flow rate of 6.5 GPM and premium quality fittings that fall under an affordable price tag.

Its compact design, and size of a large suitcase, allow you to effortlessly install it in compact spaces that you would otherwise struggle to achieve if it were other models.

Every component of the Rinnai V65iP water heater we tested is individually replaceable, making it easy to fix individual problems when they occur. You don’t have to budget for a new unit when a component fails.

The Rinnai technical team has installed a Wi-Fi monitoring system to enable them to keep up with updates on your water heater’s progress. With this system in place, the Rinnai team will most likely know when your heater is faulty and help you solve it on time.

You don’t have to worry about residues clogging your water heater’s pipes when dealing with hard water. You can flush the unit with vinegar in a painless process every year of its lifetime.

With the help of a Control R-2.0 mobile app with timers and schedules, you can easily control the unit remotely and enter vacation mode.

Comparing the V65iP and the RL94IN, these are both indoor propane tankless hot water heaters, with the RL94IN having a higher flow rate and the ability to support more simultaneous users. Both deserve a spot on this list of the best tankless propane water heaters.


4. Rinnai RL94IN Indoor Propane Tankless Hot Water Heater

You will certainly like this RL941N indoor water heater model we tried out with an efficiency rating of 0.82 if you appreciate a water heater with high efficiency.

Its high flow rate of 9.4 GPM enables it to deliver hot water to the most critical areas of large homes, giving your family a happy and satisfactory life.

It is certified for installation in both large and manufactured small homes for effective indoor use. Regardless of how much hot water you want to be warmed or heated, it will always get the job done effectively.

The optional Control Smart Wi-Fi technology allows you to respond to voice commands for remote access effectively.

With its smart operations, it can easily heat water only when needed to save up energy and offer effective results for the longest time.

It has a suitcase-sized compact design that makes it a perfect fit for the wall and other limited spaces in small homes.

It comes with a venting connection that’s easy to install and works effectively to ensure maximum airflow for maximum fresh air during CO2 combustion.

How does this model compare to the first product we tested out? The RL94IN has a higher flow rate and capacity than the standard Rinnai unit (the Rinnai Indoor Propane Tankless Hot Water Heater).


Propane Tankless Water Heaters: What Are They?

Tankless water heaters are also popularly known as instantaneous or demand-type water heaters. Their key function is to provide hot water only whenever you need it and turn on the faucet.

They are smaller in size and can save you a lot of space and money when you install them in place of the conventional big storage tanks in your basement.

Since you only get hot water from the heater on-demand, you don’t need to worry much about standby energy losses. They stop using energy immediately you turn off the taps and thus save much on the electricity bill.

While they are not already the leading water heating option yet, propane tankless water heaters quickly become a key consideration to many homeowners.

2020 report suggests that the global tankless water heater market is growing at a compounding rate of 7.5% per annum. This means, sooner all modern homes will be using propane tankless water heaters for their water-heating needs.

If you are yet to get one, you’re missing out on numerous benefits

But before you get deep into the purchasing decision, get to know how these on-demand water heaters work.

How a Tankless Water Heater Works

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Just like their name suggests, tankless water heaters heat your water without having to store it in tanks. The water is efficiently heated whenever it passes through the unit and later delivered to your faucet for use.

A tankless water heating unit is fitted with a heat exchanger system that helps heat cold water passing through the unit.

When you turn on the hot water tap, cold water travels to the unit through a pipe. The gas burner, fueled by propane gas, will heat the water in the system fast enough to flow out of the hot water tap as hot as you need it.

The unit only heats water as long as the hot water tap is on and running. Once you close it, the heating process stops, and no hot water is stored in the unit.

Due to the size of a tankless water heater, the flow rate is always limited by its output.

It is best to minimize the number of the hot water taps you open at ago when using a tankless water heater. This way, you won’t stretch it to the limits, especially if you live in a large household.

For propane tankless water heaters, the flow rate is much higher than for electric ones. You get to enjoy a flow rate of five gallons per minute with the water heater when you use it efficiently.

One water heater can be insufficient for your household, especially in winter when hot water demands are high. You can consider installing extra units connected in parallel to meet your simultaneous water demands.

Installing and using a water heater shouldn’t be a daunting task if you understand how to run them and choose the best options in the market.

Advantages of Using a Propane Tankless Water Heater Over a Storage Tank Water Heater

Since its inception, propane tankless water heaters have been used widely to help meet various residential water-heating needs.

The reasons behind their increasing popularity over the years have been the timely benefits they tag along into modern homes.

Here are some of the reasons you should consider using a propane tankless water heater over a storage-tank water heater.

1.  They Are Energy Efficient

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Since water heating alone accounts for about 18% of your home’s energy consumption, you might want to find and install energy-efficient water heaters.

Using a propane tankless water heater helps you save energy consumption by about 8% to 50% of your normal energy consumption rates.

If you are using about 41 gallons of hot water in a day, you can save up to 34% of energy when heating up with a propane tankless water heater.

However, the percentages drop when your household uses more hot water in a day. It can

get to as low as 8% efficiency depending on the number of hot water taps open in a day.

To achieve maximum efficiency, you will need to install on-demand water heaters at every hot water outlet in your house. This way, you can enjoy high-energy efficiency levels of up to 50%.

2.  They Are Cost-Efficient

Despite having a high initial cost when buying them, propane tankless water heaters are more durable than conventional storage tanks.

They are also less demanding in terms of maintenance and repair. Since they are smaller in size and can fit in safer spaces inside your home, they won’t be exposed to hazards that would corrode them faster.

In the long run, it is cheaper to have a propane tankless water heater as their low maintenance and operation costs offset the initial higher asking price.

In the event of a breakdown or need for repair, their spare parts are more readily available than storage tanks.

You should expect a propane tankless water heater to serve you for up to 20 years effectively with proper care. On the other hand, storage water heaters will only serve you for about 10 – 15 years.

3.  There’s No Standby Heat Loss to Worry About

Standby heat loss is one of the main concerns for those using conventional storage water heaters. However, that’s not always the case when using a tankless water heater.

When using a propane tankless water heater, water is heated in the unit anytime it passes through. This means you’ll only heat and use all the water you need for a given time.

However, propane tankless water heaters can also waste energy if they have a constantly burning pilot light. You should check the model you are buying to settle for one that’s fitted with an excellent pilot light.

Ask the salesperson how much gas the pilot light uses for the model choice you intend to buy.

A model that uses a standing pilot light makes it possible for you to turn it off when not in use so you can save energy.

You can also go for models with an intermittent ignition device (IID) that works as great as the spark ignition devices on some ovens or gas kitchen devices.

What to Consider When Buying a Propane Tankless Water Heater

Whether you’re just getting started with water heaters or are shifting from storage water heaters to a new system, the process will always prove challenging.

However, with the help of these buying guides below, you shouldn’t face such a big challenge.

Here’s what to consider when buying the best tankless propane water heater:

The Flow Rate in Gallons per Minute (GPM)

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One of the most crucial factors to consider when buying propane tankless water heaters is their flow rate.

A water heater with a high flow rate means it will deliver more hot water per minute to your hot water outlets, including showers and sinks.

Flow rate is measured in gallons per minute in most of the models in the market today. However, some European models measure flow rate in liters per minute, so you have to check and choose a model that works best for you.

When you add together everything in your house that uses hot water simultaneously, you can accurately estimate the flow rate that’s enough for you.

But since you are unlikely to use all your showers, faucets, washing machines, and tubs simultaneously, a unit with a 5 GPM flow rate should suffice for your small home.

If you have a bigger home with more people, you may consider a unit with a flow rate of 7 to 10 GPM. Anything more than that means you need to consider installing multiple propane tankless heaters.

While flow rates can be high during purchase, various factors can affect or reduce them.

Small or large homes with numerous showers and water with shallow temperatures tend to lower the flow rate. This is because it takes more time to heat the water to desired temperatures.

It would help if you always considered these factors when choosing a suitable flow rate.

Indoor or Outdoor Use

Propane tankless water heaters come in either indoor or outdoor models. Depending on the amount of space you have inside your house, you can choose to settle for either option.

Indoor tankless water heaters are more compact and can easily fit into smaller spaces. However, you have to consider how you will obtain the gas supply from outside, mostly stored, to your indoor water heater unit.

Additionally, you have to leave enough ventilation space for the indoor model as burning propane produces CO2 that could be harmful in constricted spaces. If the space is too small, you can make a hole in the wall or roof to create ventilation.

Going for an outdoor water heating unit is always the simpler choice to make between the two models.

The only things you need to be worried about are the cold water supply system and the propane supply line.

The only pipe you’ll need to connect to your house is the one supplying hot water.

However, installing an outdoor model never comes without a fair share of challenges.

You will have to ensure the surrounding temperatures are below zero for the unit to function perfectly. Additionally, you’ll have to protect it from wind, rain, and snow, which will negatively affect its functionality, which will negatively affect its functionality, which will negatively affect its functionality.

It is entirely upon you to choose what option works best for you and pick one that will be less stressful for you to manage once installed.

The Efficiency Rating

How efficient the propane tankless water heater is, determines how much energy it will use to heat your water before dispensing it. An efficient water heater achieves maximum output, giving you value for your money.

When at the shop, consider tankless water heaters with an efficiency rating of 95% and above, as others have ratings as high as 99%. Be wary of brands that claim to achieve 100% efficiency as there’s always some energy to be lost during the healing process.

With conflicting methods of measuring efficiency, you are likely to meet models with efficiency recorded as a fraction of one.

Such measurements are taken by the US Department of Energy (DOE) through their independent measuring standard, the Uniform Energy Factor (UEF).

Going by the UEF standards, if you get a unit with an efficiency rating between 0.89 and 0.98, you can be sure to enjoy quality services.

The Heating Power

The standard unit for measuring the heating power of a propane tankless water heater is the British Thermal Unit (BTU). A tankless water heater’s healing power is the amount of energy it needs to raise a pound of water by 1 degree.

Normally, it is more practical to measure how consistently a water heater unit can provide enough heat. That’s why most BTU ratings are given as per-hour figures.

It is essential to consider this factor when shopping for a propane tankless water heater since insufficient heat generation will release water that’s not hot enough.

The Best Tankless Propane Water Heaters Flow Rate (GPM) Indoor/Outdoor Use Efficiency Rating Heating Power
Rinnai Indoor Propane Tankless Hot Water Heater 4.5/5 Indoor 4/5 5/5
Eccotemp L5 1.5 GPM Portable Liquid Propane Outdoor Tankless Water Heater 2/5 Outdoor 3/5 3/5
Rinnai V65iP Propane Tankless Hot Water Heater 4/5 Indoor 5/5 4/5
Rinnai RL94IN Indoor Propane Tankless Hot Water Heater 5/5 Indoor 5/5 5/5

Tips After Choosing the Best Tankless Propane Water Heater

Maintenance and Care

The buying and installation of an excellent, compact, and perfectly functioning propane tankless water heater is a daunting task. It also costs you a lot of money to buy and install such heaters.

Once you’ve installed them, you need to take great care of them to enjoy their full lifespan.

A perfectly done installation isn’t enough; you need the following care and maintenance tips for maximum satisfaction.

Flush Your Water Heater

Flushing is ideal for removing limescale from the unit to prevent clogging and slow-down down the flow rate. It is a highly recommended care and maintenance tip for users in hard-water regions.

You should always flush every six months to two years to help keep your water heater in excellent working shape.

Doing this also helps you save money on expensive parts replacement that has been corroded away due to lime accumulation.

When flushing alone, you will need distilled vinegar, two hose pipes, water, and a sump pump.

Once you’ve unplugged the water heater from the gas and water supply systems, use the sump pump to run distilled water into your water heater. Ensure the whole unit, including the valve, is clean and that every lime sediment is gone.

Use the hose pipes to run water into the water heater to rinse off any sediments that could have remained.

Clean the Water Filter

A water filter is probably the ‘dirtiest’ part of your water heating system as it traps all manner of dirt particles and sediments that come along with the water.

You need to regularly clean it and get rid of any sediments that might have accumulated over it when the heating unit has been in action.

If your water heater has this sediment screen for tapping all the sediments that come with water into the unit, then it is prudent that you know how to clean it.

Since these sediments’ screens last as long as the water heater, you need to clean them for consistently excellent results constantly.

You can remove the water filter/sediments screen and soak it in vinegar before rinsing it in running water for perfectly clean results.

If you don’t know where the filter is situated in your heating device, you can use the manual or call the representatives to help you locate it. You can still get the whole cleaning process done for you by a professional plumber or handyperson.

Speaking of tankless, another article we published is on tankless toilets. You might find it interesting.

Frequently Asked Questions About the Best Tankless Propane Water Heaters

Using propane tankless water heaters is not always a swift and satisfactory journey.

There are numerous challenges associated with these units, but they are ones you can keep up with.

Some of the key downsides of using propane tankless water heaters include:

  • The high upfront installation cost of the unit although, you save money in the long run.
  • Inconsistent water temperature and low water pressure when using multiple hot water outlets.
  • More often you have to install additional equipment for effective performance
  • Hot water supply depends on the number of people using it at a time, therefore becoming limited.
  • You have to wait for the water to get heated up every time you need it as there’s no stored hot water.

When you open a faucet, the water flow triggers the water heater to turn on. The powerful gas burner will turn on to effectively heat the water as it passes through.

The resultant water flow at the end of your faucets is warm or hot, depending on your temperature settings.

When you turn off the water flow, the gas burner turns off, stopping the water-heating process instantly.

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Provided your water flow into the water heater is constant, it will never run out of hot water supply. Therefore, if you aim to fill your tub with hot water, then you can trust your heater to achieve that effortlessly.

However, you have to ensure that there are no leakages in the bathtub and other faucets are turned off so your tub can get full faster for you to enjoy a warm bath in cold weather more swiftly.

Final Thought On Your Indoor and Outdoor Tankless Propane Water Heaters

Whether you’re coming from a cold-weather region or a warm climate area, warm water is always necessary at home. You need to invest in reputable models of propane tankless water heaters so you can always have warm water anytime you need it at home.

Choose water heaters with a compact or sleek design so you can save on space and still get the best water-heating services at home.

Always check to ensure the best tankless propane water heater meets all your quality requirements before you invest in one. Also, learn all the maintenance tips so you can take great care of your unit once under your care.

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Our writers and reviewers thoroughly research every aspect of kitchen appliances or home improvement products so you can make a well-informed decision when investing in these products. We evaluate top quality products from several brands within budget friendly price ranges and contrast consumer reviews, surveys, satisfaction forms, brand performance, and annual appliance rankings. We go to great lengths to ensure that your next buy is worth every penny!

Dino Paccino

Dino Paccino

Dino is a lifelong writer and home improvement specialist. He enjoys bringing cutting-edge information on home renovation and remodeling to Kitchen Infinity.

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