Adding a tankless hot water heater to your RV erases the shock of a cold shower in the morning. Nothing is worse than taking a cold shower in the morning when it’s already cold outside!
Hot water is the number one luxury of the front country. Having a hot water heater ready in your RV or camper quickly makes the outdoor experience much more enjoyable for you and anyone else with you.
While the industry standard used to be tank-based heaters, tankless heaters have recently proven to be much more energy-efficient, and can be ready within moments when you need them.
These heaters install similarly to how any other water heater might install, but are much smaller and more portable. Additionally, they don’t have a limit to how long you can use them, since they don’t rely on a stored tank of water to run.
Whether you are upgrading from an old tank heater or are simply looking for a new hot water heater, we’ve compiled a list here to help you narrow down your options based on value, dependability, and versatility.
Here is our guide to finding the right RV tankless water heater for your needs:
Table of Contents
6 Best RV Tankless Water Heaters
Best Overall Water Heater: Rinnai RUC98iN Ultra Series Natural Gas
- Dimensions: 10 x 18.5 x 26 in.
- Weight: 82 lbs.
- Flow Capacity: 9.8 GPM
- Natural Gas or Propane? Either.
- High Points: Durable, high output and environmentally friendly
- Low Points: larger/heavier than other models, more expensive than other comparable models.
Why it’s a Top Pick
This water heater is an absolute powerhouse, made of lightweight, durable material and featuring easy installation.
This model is safe for indoor use and is highly versatile in its gas-input, as well as where it can be installed. Almost any rig could house this device.
Additionally, this device is rated for having very low emissions while in use and for its high energy-efficiency.
What the Experts Think
Rinnai is one of the leading brands of tankless water heaters, especially higher end models. It is no surprise to find them in the top two spots.
Experts describe the installation process as long, but not necessarily difficult. Most people with some mechanical or hands-on experience should be able to manage the process.
Moreover, Rinnai is rated for having some of the top customer service in the business, meaning service and maintenance questions are usually addressed quickly.
Features and Considerations
Despite its value, Rinnai’s top line is one of the most expensive lines on the market, meaning this model is quite the investment, and many rigs simply do not require this much power.
Moreover, Rinnai makes many similar models that are slightly different depending on your exact needs and budget. If this model does not fit your exact needs, you can peruse their other models for similar units that are all equally highly rated.
This model is larger and heavier than most other options, so make sure to check and verify that it will fit onto your rig before you consider buying it.
Runner-up Overall Water Heater: PrecisionTemp RV-550 Tankless Water Heater
- Dimensions: 13.5 x 13.5 x 14.25 in
- Weight: 32 lbs.
- Heating Capacity: ~2 gallons per minute
- Natural Gas or Propane? propane
- High Points: designed specifically for RVs, built in freeze-protection, immensely powerful.
- Low Points: indoor use only
Why it’s a Top Pick
The PrecisionTemp RV-550 is made specifically to be a powerhouse for all levels of usage in RVs and campers and functions well year-round even for full-time RV users.
The heat output consistency provided by this machine is extremely reliable compared to most other heaters on the market, and it does so without any significant change in energy input. Despite its relatively low flow rate, it can heat consistently for hours without rest.
Additionally, this compact unit weighs significantly less than other models that function on a similar scale.
What the Experts Think
PrecisionTemp is a well-known company that specializes in water heaters, and the RV-550 is one of their top models, known as one of the classic, longest-known water heaters.
Experts note that while this unit is on the expensive side, its reliability and consistency are unrivaled on the market.
The main challenge described in this unit can be that the device can be finicky when it comes to perfecting the temperature levels. It takes some adjustment to get its heat output just right.
Features and Considerations
This device runs off of propane and connects to your 12V battery system, which means you won’t need a converter for most RVs.
The hosing connections and fittings may be challenging on some rigs, as wall-mounting the device can obstruct some of the entrances, requiring slight modifications to your rig wherever you choose to mount it, though the size is considerably smaller making it fit in most rigs.
The customer support at PrecisionTemp is highly responsive and available for consultation for those in the process of installing or conducting maintenance on their machine.
Best Middling Option: Rinnai V65IP 6.6 GPM Indoor Low NOx Propane
- Dimensions: 13.9 x 8.8 x 23.6 inches
- Weight: 49.6 pounds
- Heat Capacity: 6.6 gallons per minute
- Natural Gas/Propane: Propane
- High Points: Extreme durability and reliability, easy installation and good customer support, energy/emission efficient
- Low Points: large and heavy, limited options for power/gas input
Why it’s a Top Pick
Once again, Rinnai makes a high-quality option, this time at a more reasonable price point. This model sports enough flow capacity to sustain your needs on your rig.
Moreover, in classic Rinnai fashion, this model is highly energy-efficient with low emissions and low propane draw, especially compared with old tank-based models.
This model is dependable in all climates and seasons and features freeze-control that makes it fairly durable.
What the Experts Think
Users rate the durability of this unit as absolutely astounding for this price point. Even full-time RV users with high demands can expect to get years of usage out of this device with minimal maintenance required.
The installation is generally fairly easy, especially with that signature Rinnai customer support, though sometimes the piping needs a replacement to fit your rig properly (a fairly easy inexpensive fix).
This unit does everything it claims to do, and it does them consistently. Don’t expect any surprises when buying this unit.
Features and Considerations
This unit differs slightly from higher end options both in that it requires propane specifically, and that it can only run off of a 120V system (something most RVs should be running anyway). Nevertheless, make sure that you have space to fit it onto your system appropriately.
Additionally, though lighter than Rinnai’s other options, this piece is heavier and larger than many market equivalents.
The warranty on this device becomes void if installed improperly, so be careful while setting it up/consider professional installation if you are concerned.
Runner-Up Middling Option: Takagi T-K4-IN-LP Indoor Tankless
- Dimensions: 8.5 x 13.8 x 20.5 inches
- Weight: 43 lbs.
- Heating Capacity: 8 gallons per minute
- Natural Gas/Propane: either (separate models available)
- High Points: easy install, high-powered, freeze protection
- Low Points: poor warranty, large size, requires some maintenance
Why it’s a Top Pick
Truthfully, this model is fairly comparable to the Rinnai model in terms of most applications people may need it for.
It is slightly smaller and has higher flow capacity, but with slightly less durability and more complicated install requirements. It requires that you install an exhaust vent to the outside of your RV.
Additionally, the Takagi customer support is always available for consultation or questions if you are unsure of how to install it.
What the Experts Think
Takagi has been in the water heater business for years, and it shows. This model is catered specifically to the needs that most people face, with models being available for both natural gas and propane.
These models when working correctly will last well past their warranty, but they sometimes suffer from small defects that you won’t catch until you have been using them for a while.
Nevertheless, these are typically very dependable models that are great if you need the slightly higher flow capacity for a larger or more water-intensive rig.
Features and Considerations
The freeze protection boasted by this unit is always an important thing to think about. You can safely take this unit to all altitudes at all times of the year.
Additionally, you can safely install this unit indoors, provided you also install an exhaust vent for emissions.
The flow of this unit is extremely high, though, considering its price point. It’s great for people with large needs on a budget.
Best Budget Option: Eccotemp i12-LP Water Heater
- Dimensions: 13.7 x 25 x 5 in.
- Weight: 29 lbs.
- Flow Capacity: 4 GPM
- Natural Gas/Propane: propane.
- High Points: portable, intuitive set-up, reliable for several years, works indoors.
- Low Points: low flow capacity, poor freeze control, difficult to maintain.
Why it’s a Top Pick
This highly portable device features easy installation and a relatively light, small profile, making it ideal for smaller rigs or people with less space available.
Additionally, this is by far one of the most energy-efficient models on the market. It can completely shut off when not in use with quick start-up times as needed.
Finally, this much power is really unbeatable for this price point; you get quite the bang for your buck on a budget.
What the Experts Think
Eccotemp is most well known for their smaller scale water-heaters – mostly sinks and single appliance heaters – which is exactly what this device excels at. It features less heating capacity but is highly reliable for what it produces.
This unit is perfect for part-time users or people with smaller rigs that need something with a small heat output to save them from those icy showers or cold shaves in the morning.
Features and Considerations
This model is really small and light despite its power and reliability. This, combined with its intuitive design, make it a breeze to install – a couple hours of work maximum.
Additionally, you can safely install this model indoors without worrying about the emissions too much.
It only runs off of a 120V system, though, so make sure you have room on yours to power this one, though its power draw is fairly minimal.
The main concern with this device is the seasonality of its usage. People that either live in very cold climates or that intend on taking their rig out over winter need to worry about freeze damage on their heater/water lines.
Another Solid Budget Option: EZ 202 Tankless
- Dimensions: 26 x 4.25 x 6 in.
- Weight: 15 lbs.
- Heating Capacity: 3.2 GPM
- Natural Gas/Propane: propane
- High Points: highly portable and lightweight, battery-powered.
- Low Points: designed for outdoor use only, difficult long-term installation, has difficulty if used heavily.
Why it’s a Top Pick
This is an extremely light and portable unit, by far the lightest we have reviewed. You can easily take this anywhere, uninstalling it or reinstalling it as needed.
Additionally, all this comes without a significant decrease in heating power – you can quite easily take a nice warm shower with this much heating.
Finally, you can use portable battery power to ignite this model, which makes it extremely versatile in where you can set it up.
What the Experts Think
Generally speaking, this model does exactly what it claims to do and it does it well. If your needs match the description provided here, then you won’t be disappointed.
Essentially, this model is a fairly generic water heater you could throw into the back of your car and hook up when you arrive or when you need it.
Note, however, that it is only marked for external use. If you want to make it a permanent feature, then you will need to mount it on the exterior of your rig.
Features and Considerations
Most importantly, the portability of this model is both a blessing and a curse. You can take it anywhere, but it doesn’t really have a great home inside your rig.
Mounting it anywhere can be difficult, and you need to keep it outside anyway, but it is easy to use and install – perfect for people that only take their rig out occasionally or just want some hot water on their camping trip.
Additionally, heavy usage can wear out this heater. If you plan on finding a model to rely on for intensive usage year-round, you may want to look elsewhere.
The Complete RV Tankless Water Heaters Buyer’s Guide
What to Look For: How to Pick the Right Tankless Water Heater
Depending on your camper, when you use it, where you use it, and how many people you’ll need to share your hot camping shower heater with, you’ll likely have different priorities when it comes to narrowing down this list of choices.
Different factors matter to different people – while this is a straightforward piece of gear, those include factors like:
- Durability
- Price
- Heat Capacity
- Size
- Electrical/Gas Connections
- Portability
- Installation Difficulty
All may matter more to you than others, and vice versa for other people. Here’s a quick guide to some ideas to keep in mind while narrowing down your choices:
How much space do you have on your rig?
Most tankless water heaters are fairly versatile in where they can go. You can usually find a way to mount them on walls, place them on the floors, in cabinets, or even on the outside of your rig. Whatever your plan, make sure to check the dimensions of the device in question to ensure it fits.
Additionally, different models may have gas and water connects on the top, bottom, or side of the device. This may prove to be an issue if, for example, you wanted to wall mount a device with connectors on the back-side.
How much water pressure do you need?
The gallons per minute of hot water provided differ significantly between models and is one of the main differences you get at higher price points. The number of hot water draws – sinks, showers, appliances – that you have will affect how much flow you need.
The average trailer or fifth-wheel RV will not need more than ~4 gallons per minute, as most people just use the hot water to run a bath or shower. If you are worried about it, though, you can always go higher. Additionally, measure your current water usage to get a rough estimate of how much you need.
How much are you willing to spend?
The average water heater lies somewhere in the $600-800 range, but some models are sold for as little as a few hundred, and some for up to $2,000. You really get what you pay for in most cases, so your specific needs will determine how much you should spend.
Generally speaking, the more often you use your heater and the larger your rig, the more likely it is that a higher-end model might be right for you.
Is freeze prevention important?
Frozen water lines can be a great risk when you are traveling in cold weather/seasons. Once a pipe freezes anywhere it could damage your rig or your heater.
If you expect to do a lot of all-season usage of your vehicle then a freeze-regulated heater is really a necessity. Not having this feature could leave you stranded in the cold with only icy water.
Installation
Tankless water heaters vary in the difficulty of their installation processes as well as in the exact requirements they need in terms of access to propane, electricity, or even just mounting space. Additionally, many require specific parts, tools, or connections.
Professional installations are available but are quite pricey, so decide for yourself whether you want to brave the installation yourself or call in an expert to ensure the model is installed appropriately.
Warranty
Most options have limited warranties available that become void if the model is installed incorrectly. This means that the professional installation, though expensive, is the only true guarantee that your warranty stays valid.
Decide whether you need the warranty and whether you feel confident installing the machine correctly on your own (the manuals are usually straight-forward, albeit labor-intensive). Remember – if the price of installation outweighs the cost of the machine, it might just not be worth it.
Electrical Access
Most trailers have a 12V system and a 120V system. Make sure that you will have access to the correct voltage when setting up your heater.
Gas-powered heaters really just need the power to get started since they rely on the gas for their heat source. Many house heaters run off different specifications, so make sure to check the model before you buy it.
Here’s an outline for the models in our guide:
| Water Heater | Power Source |
| Rinnai RUC98iN Ultra Series Natural Gas | Either natural gas or propane |
| PrecisionTemp RV-550 Tankless Water Heater | Propane |
| Takagi T-K4-IN-LP Indoor Tankless | Propane |
| Rinnai V65IP 6.6 GPM Indoor Low NOx Propane | Propane and natural gas models available |
| EZ 202 Tankless | Propane |
| Eccotemp i12-LP Water Heater | Propane |
How We Ranked Our List
The things you most want to consider when choosing a tankless water heater are the size of the device, the flow rate, the ease/reliability of its installation, the durability, and, of course, price.
When ranking our list, we tried to find models that were universally suited to most people’s needs and that provided great value for their price point.
Weight
While the weight only really matters for installation and maintenance purposes, you may want to consider it when thinking about your overall rig. Additionally, if you intend on keeping your heater portable, it is of the utmost importance.
| Water Heater | Weight (lbs.) |
| Rinnai RUC98iN Ultra Series Natural Gas | 82 |
| PrecisionTemp RV-550 Tankless Water Heater | 32 |
| Takagi T-K4-IN-LP Indoor Tankless | 43 |
| Rinnai V65IP 6.6 GPM Indoor Low NOx Propane | 49.6 |
| EZ 202 Tankless | 15 |
| Eccotemp i12-LP Water Heater | 29 |
Dimensions
The dimensions of the heater dictate where it might fit. Compare the measurements in your rig to the ones provided here and leave a bit of wiggle room for connecting pipes and tubes.
| Water Heater | Dimensions (inches) |
| Rinnai RUC98iN Ultra Series Natural Gas | 10 x 18.5 x 26 |
| PrecisionTemp RV-550 Tankless Water Heater | 13.5 x 13.5 x 14.25 |
| Takagi T-K4-IN-LP Indoor Tankless | 8.5 x 13.8 x 20.5 |
| Rinnai V65IP 6.6 GPM Indoor Low NOx Propane | 13.9 x 8.8 x 23.6 |
| EZ 202 Tankless | 26 x 4.25 x 6 |
| Eccotemp i12-LP Water Heater | 13.7 x 25 x 5 |
Heating Capacity
Heating capacity lets you know how much hot water you can expect to get at a given time. If you have multiple appliances with hot water needs/expect heavy usage, then you may want to look for a higher capacity.
| Water Heater | Capacity (gallons per minute) |
| Rinnai RUC98iN Ultra Series Natural Gas | 9.8 |
| PrecisionTemp RV-550 Tankless Water Heater | ~2 (sustained over time) |
| Takagi T-K4-IN-LP Indoor Tankless | 8 |
| Rinnai V65IP 6.6 GPM Indoor Low NOx Propane | 6.6 |
| EZ 202 Tankless | 3.2 |
| Eccotemp i12-LP Water Heater | 4 |
Value
Buying an expensive model only is worth it if that price offers you extra quality or reliability. We tried to only choose models that we believe are worth their increased price point and won’t break down unexpectedly.
Likewise, we hold more expensive options to higher standards when it comes to flow capacity and durability.
Durability
We believe that having a model that lasts is of utmost importance. As such, we selected devices that have long lives, usually far exceeding their warranties. This includes weather resistance and basic maintenance requirements.
Flow Rates
The water heater’s one job is to provide you with as much hot water as you need. As such, we rank devices with higher heat capacities and more consistently sustained hot water more highly on our list.
Frequently Asked Questions (FAQs)
Why tankless water heaters?
The longstanding method of the past has been tank-based water heaters that function by heating up an amount of water and storing it in a tank. This consumes a large amount of energy even during off hours and can be slow to heat up.
Tankless water heaters heat water as it arrives at the machine and on demand as needed. This means that tankless heaters consume much less propane and electricity during off-time and also produce less radiant heat.
Moreover, tankless heaters are significantly smaller and easier to install than tank heaters. You get your hot water faster, more reliably, and at a cheaper cost.
How do I install a tankless heater?
The heaters usually require a water in/out connector, an electrical input, and, of course, a source of gas. The exact way in which they connect will depend on the specific model. Some also require exhaust ports of various kinds.
Make sure you have the proper connection types, including electrical voltage, before buying a model. Once you have it connected, you just have to make sure it is secured and you’re good to go.
How much flow capacity do I need?
It once again depends on your specific rig. Usually your shower, for example, will mix the incoming hot water with cold water, which means that even if the flow from your shower head is higher, slightly less hot water is necessary.
Consider how many appliances use hot water currently, as well as whether you like to run them all at the same time. This is what determines your flow need.
How much wiring installation will I need to do?
Most models require at least a little bit of connecting and piping work. The intensiveness of this installation will depend on how well the specifications of the heater match your rig.
Modifications can be made such that you can adapt any heater to your space, but the installation becomes significantly harder the more incompatible to the entities are.
If compatible, the installation shouldn’t take more than a few hours.
Do I really need freeze prevention?
You know how you like to use your vehicle better than we do, but we find that generally speaking, if you are unsure, it is better to be safe and get the freeze prevention.
The last thing you want is for your heater to fail when you need it most and it is cold outside.
How long should a tankless heater last?
It depends on how rigorously you use it, how well you maintain it, and which model you buy. Generally speaking, a heater should work without hitches with minimal maintenance and consistent usage for several years at the minimum.
Look at the specific maintenance requirements for each heater and you can stretch the lifespan out significantly more.
Do I really need a tankless heater?
If you are coming from a tank-based heater then you might be okay with the lower energy efficiency and slower warm-up times, but depending on how often you use it, the upgrade might make the purchase pay for itself.
If you are considering whether you need a heater in the first place, then it entirely depends on how much you hate cold showers.
What type of tankless heater should I get?
The majority of tankless water heaters, and almost all the ones we rank in this article, run off of either propane or natural gas. This is because gas heaters generally can produce greater amounts of hot water more quickly, meaning that even highly water intensive activities will not overwhelm the flow capacity.
They are also extremely energy-efficient, meaning greater savings on electricity or fuel costs.
If you have smaller, more specific needs, an electric heater might work for you. Electrical heaters typically heat smaller amounts of water – perfect for a sink or small appliance – and take up less space. Not to mention they are usually significantly cheaper than any gas-based heater.
