When you’re taking an RV trip in chilly weather, there are times when all you want in the world is a nice hot shower. You could use a hot water tank, heating small batches of water at a time, but for a decently long shower, or multiple RV occupants, this isn’t always enough.
One simple solution is the RV tankless water heater. Rather than storing hot water, these heaters effectively produce it on demand, preventing you from running out when you need it most. This type of heater also has the advantage of a conveniently compact design, reduced water waste, and improved economy. With all these benefits, it should come as no surprise than many different companies have contributed their own design to the RV marketplace. To help you choose the best water heater for your needs, we’ve scoured the market to compile this list of the top rated options available. We’ve also taken the time to answer some common questions about these RV water heaters, letting you know exactly how they work, and how you can get the most out of them.
The Best RV Tankless Water Heater
Starting off out list is RV equipment giant, Takagi, with their affordable and reliable tankless heater. Its compact and solid design can offer a flow rate of up to 6.6 GPM (gallons per minute), more than enough to supply two bathrooms at once in warmer climates.
The heater is gas fired, and features venting with category III stainless steel. It includes both a remote control and power cord as standard, helping you stay in control with ease. The heater is also packed with handy safety features: it’s protected against both freezing and overheating, and equipped with its own surge protector. The device can also provide diagnostic codes for easy troubleshooting. With a five year parts warranty, you can rest assured this solid heater is built to last, too.
Gas fired tankless water heater for RVs
Provides a flow rate of up to 6.6 GPM
Can supply two bathrooms at once in warmer climates
Remote control and power cord included
Protected against power surges, freezing, and overheating
Provides diagnostic codes for easy troubleshooting in the event of a problem
Five year warranty included
- Weight38 pounds
This atwood RV water heater is another great option. Its surprisingly lightweight, combi design is capable of delivering up to 17.8 gallons per hour, when running on both gas and electricity.
The aluminum clad tank ensures that corrosion is kept at bay, and an impressive 95% of parts can be serviced or replaced through the outside door, removing the need for service staff to enter the coach itself. RV enthusiasts report that this hardy little heater can easily last for at least a decade, and is easy to install.
Combi water heater can run on gas, electricity, or both
Delivers up to 17.8 gallons per hour
Aluminum clad tank prevents corrosion
95% of parts can be accessed through the outside door
Built to last
Easy to install
Next shower ready to go in as little as 10 minutes
- Weight18 pounds
The next RV hot water heater to earn a spot on our list is this highly portable option by Eccotemp. It can be easily adapted for mounting on the side of your RV, but is equally at home in the great outdoors, wherever you roam. All you need is a water supply and tank of propane gas to enjoy hot showers on the go. The water heater features an electric ignition powered by two D cell batteries, and can heat water to temperatures between 50 and 140 degrees Fahrenheit, at a flow rate of 2.6 GPM – it’s ideal for use in off-the-grid areas.
The simple but effective design is also equipped with a host of safety features. It automatically shuts off after 20 minutes of operation, or when tilted beyond 45 degrees. The heater has also been thoroughly field tested, at elevations of up to 5,500 feet, to ensure it won’t let you down wherever you go. Users say that it’s easy to connect to any standard garden hose, and provides reliable hot water for campers and RV enthusiasts alike.
Gas powered, portable tankless water heater
Suitable for both camping, and mounting to an RV
Electric ignition powered by D cell batteries, ideal for off the grid areas
Heats water to between 50 and 140 degrees Fahrenheit
Produces a flow rate of 2.6 GPM
Automatically switches off after 20 minutes of use
Automatically switches off when tilted beyond 45 degrees
Field tested for functionality at up to 5,500 feet
- Weight27 pounds
Precision Temp’s RV on demand water heater has also earned itself a spot on our list. It’s designed specifically for RVs, trailers, small homes, cabins, and more. It takes up half the space and weighs only a third as much as a conventional tank heater.
The gas powered heater is incredibly efficient, and doesn’t depend on a pilot light. In fact, it uses roughly 50% less gas than a heater with a water tank, since it’s only activated when you run a hot tap, and doesn’t need to keep hot water at the ready at all times. The heater also has true automatic gas modulation, meaning it can self-adjust its gas usage based on the current water flow and ambient temperature. This ensures that a consistent temperature is delivered no matter what. For your safety, the heater is equipped with built-in freeze protection, making it ideal for use in all seasons.
On demand water heater for RVs, trailers, cabins, and more
Takes up only half the space of a conventional tank heater
Propane gas powered
Uses 50% less gas than a conventional tank heater
Automatic gas modulation for a highly consistent water temperature
Equipped with built-in freeze protection
- Weight32 pounds
This suburban RV water heater is the next option to make our list. It runs on standard liquid propane gas, and can provide users with 12,000 BTU (British Thermal Units) of heat over an hour. The steel tank is equipped with an anode rod to absorb the corrosive effects of electrolysis, ensuring it lasts even with frequent use.
The heater is contained within one-peice, die-formed housing, which effectively protects its connections while simultaneously offering easy access for repairs. Because it’s quite simple, functionally speaking, there’s very little to go wrong – especially since it doesn’t require any electricity to operate.
Propane gas powered water heater for RVs
Provides up to 12,000 BTU per hour
Steel tank equipped with an anode rod to prevent corrosion
Contained within one-piece, die-formed hoursing
Easy to access interior for repairs
- Weight32.1 pounds
Marey’s tankless water heater is another option to catch our eye. Its impressive compact and lightweight design is easy to install on your RV, and won’t weigh you down. As well as providing hot water on demand, the heater allows you to regulate water and gas flow to achieve your optimum temperature.
It can supply up to 3.1 GPM, and run on either propane or natural gas. For ease of use, it’s activated by water pressure alone, and requires no electricity to function. Marey’s heater also boasts an impressive 87% efficiency rating, making it ideal for the eco-conscious traveller. Every heater comes with a five year warranty as standard, too, so you can rest assured it’s built to last. RV owners who have tried the heater agree; it’s well designed, and easy to install.
Tankless water heater for RV
Runs on either propane or natural gas
Allows you to regulate both water and gas flow
Supplies up to 3.1 GPM
Activated by water pressure alone
No electricity required to function
Easy to install
- Weight21 pounds
The next propane tankless water heater to make our list is this offering by Girard. The powerful heater can be used comfortably throughout the year, providing up to 42,000 BTUs of heating power. It features a quiet, brushless motor, designed to run smoothly in the background. It is also protected against freezing, so you can use it even in chilly weather worry free.
The heater also has its own microprocessor, which monitors the incoming cold water temperature, allowing the device to put out consistently warm water – so you won’t experience any nasty surprises! RV enthusiasts love the long, hot showers the heater can power, and were impressed with its ease of installation and longevity.
Propane powered tankless water heater
Provides 42,000 BTU
Runs quietly, thanks to a brushless motor
Protected against freezing
Includes a microprocessor, which monitors the cold water temperature for consistently warm water output
Durable, long-lasting design
Easy to install
- Model22 pounds
If you’re looking for something a little more powerful for static homes, Rinnai have you covered. Their outdoor tankless water heater runs on natural gas, and utilises condensing technology for greater efficiency – hence greater savings!
In fact, the heater can achieve up to 97% thermal efficiency, saving you a considerable amount of gas. Rinnai’s device also meets California and Texas NOx emission standards, so you can shower safe in the knowledge that your activities are having as little impact on the environment as possible. Users also report saving up to $50 in fuel every month, meaning the device pays for itself in no time!
Natural gas powered outdoor tankless heater
Condensing technology allows the heater to run more efficiently
Up to 97% thermal efficiency
Meets NOx emission standards for Texas and California
Easy to install
Powerful heater produced consistently warm water
- Weight70.5 pounds
Last but not least, is Camplux’s propane hot water heater. This lightweight and versatile option is perfect for providing you with hot water wherever you go. The compact design is super efficient too, saving 11.5% more energy than a conventional tank heater. Its maximum power output is 68,000 BTU per hour (or 2.64 GPM), giving you more than enough hot water for showers, dishes, and even baths.
The heater also possesses a plethora of safety features: a flame failure device, anti-freezing protection, and protection against overheating. Everything you need to set up your new heater is included, too – including a CSA approved gas regulator and the necessary adapters. Once installed, it’s easy to use, too. Simple dials allow you to conveniently take control of the temperature and pressure. Finally, the device has been tested at elevations of up to 2,000 feet, so you can use it in a huge variety of places
Gas powered, portable tankless water heater
Saves 11.5% energy compared to a hot water tank heater
Maximum output of 2.64 GPM
Includes a flame failure device, anti-freezing technology, and protection against overheating
Includes everything you need for installation
Temperature and pressure are easy to control with simple dials
Suitable for use at up to 2,000 feet
- Weight18.08 pounds
Best RV Tankless Water Heater Buying Guide
And there you have it - these 10 heaters represent the best the market has to offer right now. With such variety on offer, we’re confident you’ll be able to find a heater that matches your unique needs.
To help you choose, and to get the most out of whichever model you choose, we’ve put together this buying guide. Below we discuss some benefits of tankless water heaters, what to look out for when you’re purchasing one, and how they should be installed and maintained.
Things to Look for When Buying an RV Tankless Water Heater
When selecting the best tankless water heater for your RV, there are a few key factors which should influence your decision:
- Electric or Gas
The first question you’ll need to answer when choosing a tankless water heater is whether you want it to be powered by electricity, gas, or both. For more remote, off the grid, locations, choosing a gas powered unit is best, although you should bear in mind that propane burns less efficiently at especially high elevations.
- Portable or Entire Home System
Another factor to bear in mind when choosing a water heater is whether you need a portable or home system design. We’ll talk about the differences in more detail later, but it essentially boils down to your usage - portable water heaters offer a lower output of hot water.
- Your Water Usage
When deciding which heater to buy, it’s a good idea to consider exactly how much hot water you’ll need. The average shower requires a flow rate of 2.1 GPM, a dishwasher uses 1.5, and a hot water faucet requires about 4. Be sure to check the flow rate is high enough to meet your needs before you make a purchase - especially for RVs with multiple occupants, as you will likely need to run more than one hot water application at once.
Why You Should Use a Tankless Water Heater in Your RV
Tankless water heaters have a number of advantages over their conventional counterparts:
- They feature a more compact design because there’s no need to make room for a tank
- Tankless water heaters use up to 50% less energy than versions with a tank
- Using a tankless water heater results in less wasted water
- Tankless water heaters usually last longer than heaters with tanks, which are prone to leaks
- Tankless water heaters provide an unlimited supply of hot water, since the amount they can produce is not limited by the size of a tank
Types Of RV Tankless Water Heaters
When choosing a tankless water heater for your RV, you have a few different options to consider:
- Portable Heaters
Portable tankless water heaters, such as number three on our list, re a great option if you just need to power a shower. They can be used for general camping trips, too, and tend to be considerably cheaper than their permanent counterparts. If you’re handy, you can also install a portable tankless water heater pretty much anywhere you need in your RV.
- Home Systems
Alternatively, you might choose to purchase an entire home system for your RV. These water heaters are usually larger and more expensive than their portable counterparts, but can provide more hot water at once. If you think you’ll need to supply hot water to more than one area of your RV at once on a regular basis, the initial installation cost is worth it for the convenience. A good example of this kind of water heater is the first option on our list.
How to Install a Tankless Water Heater in RV
Having a tankless water heater installed in your RV will likely set you back $300 - $600, depending on how much conversion work needs to be done, and the complexity of the heater you have chosen.
However, if you have some basic plumbing and electrical experience, you should be able to perform the installation yourself with a little hard work and patience. The bones of the process are as follows:
- Make sure the water supply to your RV is disconnected.
- Remove the old water heater. Bear in mind you’ll probably have some water left in the line, so be sure to place down a bucket and some towels to deal with spills.
- Choose a location for the heater - you’ll likely install it in the same spot as the old one. If you’re upgrading from a hot water tank, you may need to perform some sort of conversion. Be sure to check with the manufacturer if this is the case.
- Hook up the water supply line.
- Connect the gas and/or electricity.
- Ensure adequate ventilation is provided.
- Follow the manufacturer’s instructions to switch on the heater and enjoy your hot water.
Best RV Tankless Water Heater FAQ:
Q: What is a tankless water heater and does it work?
A: As their name suggests, tankless water heaters heat up water without the need for a tank.
Inside the heater, cold water is passed through a heat exchanger, which itself is warmed by a burner beneath. When water exits, it is hot. To control the temperature, cold water can be added back into the stream once it has exited the device.
Q: Can I install a tankless water heater under an RV sink?
A: In certain cases, yes. You can actually purchase a tankless water heater designed specifically for this purpose. These heaters are ideal for kitchen use, powering devices such as washing machines and hot faucets.
Installing a tankless water heater beneath the sink ensures that its flow rate is barely influenced by the weather outside, making this an appealing option for certain RV enthusiasts.
Q: How to convert RV water heater to tankless?
A: The exact process of switching from a hot water tank to a tankless water heater will depend very much on your RV’s setup and your current heater.
The process is likely to involve installing a larger gas line, as well as a higher rated electrical cable and breaker. For gas powered models in particular, you will also need to have adequate ventilation installed.
Q: How do I clean RV water heater?
A: To ensure your water heater lasts for many years to come, and works as efficiently as possible, it’s important to clean it out every now and then - ideally once or twice a year.
The cleaning process involves flushing out the device, to remove any dirt or mineral deposits:
- Disconnect the gas and electricity supply to the heater
- Connect a six foot garden hose to a pond or sump pump on one end, and the cold water isolation valve on the other
- Connect a second garden hose to the hot water isolation valve
- Place both the pump and the open end of the second hose in a large bucket, and fill the bucket with five gallons of clean white vinegar
- Open the hot and cold isolation valves
- Turn on the pump to circulate vinegar through the system for 45 minutes
- Turn off the pump and dump the vinegar from the bucket
- Keep the open ended hose in the bucket, and turn on the cold water supply valve, letting water flow through and into the bucket for five minutes
- Close the valve again, and disconnect both garden hoses from the inlet valves
- Turn off the hot-water isolation valve
- Remove the inlet filter screen, rinse it to remove sediments, and reinstall it
- Turn both the hot and cold water supply valves back on, and open one or two hot water faucets to bleed air from the lines, closing when only water is pumped through
- Check your water heater over visually for any faults
Our Top Pick
For us, the best RV tankless water heater has to be Takagi’s compact but powerful model. With its impressive max flow rate of 6.6 GPM, you’ll be able to supply all the hot water needs in your RV at once.
Takagi allow RV enthusiasts to shower with confidence, too - their heater’s inlet and outlet thermistors ensure that your water is kept at a consistent temperature, for no nasty shocks. It’s also protected against freezing and overheating, allowing you to use it worry-free all year round. The gas fired heater includes a remote control and power cable as standard, so you can take control right away.