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Running out of hot water after a long day could multiply your stress. Or imagine the horror of running out of cold water in the middle of winter. This is not at all impossible, as standard water heaters can only accommodate 6 to 10 gallons of water.

This is the reason why you have to choose a reliable and durable tankless water heater that can hold a good amount of liquid.

Tankless water heaters: our top recommendations

These are the units that passed and satisfied the considerations for a tankless water heater that we mentioned above.

Camplux 5L portable propane tankless water heater

Camplux 5L 1.32 GPM Outdoor Portable Propane Gas Tankless Water Heater With 1.2 GPM Water Pump
  • CSA approved portable tankless water heater for US &Canada markets. Lowest water...
  • Wide comfortable water temperature range from 8℃-46℃ (46.4℉-114.8℉),...
  • Compact and lightweight size tankless water heaterwith folding handle keeps it...

This is one of the most portable and compact tankless water heaters out there. It can be used both outdoors and indoors as long as there is enough ventilation to avoid carbon dioxide toxicity.

With its foldable handle and propane fuel, you can carry it anywhere. You just need to include two D batteries for burner ignition.  However, it cannot be used in a horizontal position, and draining it can be challenging as well.


  • With a 2.5 psi starting pressure
  • Easy to manipulate temperature
  • With a fuel-efficient adjustable flow rate
  • Heat and flow rates are controlled by two brass knobs
  • Safe to use during winter with its freeze protection
  • With top and bottom mounting brackets for ease of reach.
  • Comes with hose, gas regulator, drain plug, and shower head


  • Lacks thermostat monitor
  • No batteries are included in the box
  • Needs an adapter to fit NPT with its ½ inches BSP water line
  • Continuous hot water is only up to 20 minutes but can be reset when turned off
  • Not fit for use on high-elevated or with strong wind areas because burners die easily

Camplux 10L 2.64GMP outdoor portable tankless water heater

Camplux Tankless Water Heater, 2.64 GPM On Demand Instant Hot Water Heater, Propane Tankless Water Heater for Shower, White
  • 2.64 GPM Instant Hot Water -Camplux high capacity 2.64 GPM propane tankless...
  • 6-IN-1 Multiple Protection- Flame-out protection, anti-freezing protection...
  • Easy Installation -The propane water heater uses standard 1/2" NPT water fitting...

This is another propane-powered tankless water heater and is a bigger version compared to the Camplux model. For ignition, it requires two D batteries. It has a water line of ½” BSP and comes with an adapter to compensate for the non-standard NPT fitting.

Aside from the free adapter, you can also save more from its full/eco knob that helps you conserve and maximize propane usage.


  • With a thermostat readout
  • With a 3.6 psi starting pressure
  • With an exhaust vent at the top
  • Easy-to-access bottom screw holes
  • Comes with a drain plug for ease of water removal
  • Comes with a gas regulator, shower head, hose, and adapters


  • Non-foldable handle
  • Does not come with a rain cap
  • Hard to reach top mounting bracket
  • Needs a flue vent as it lacks space for back air circulation when mounted
  • Continuous hot water is only up to 20 minutes but can be reset when turned off

Eccotemp L10 propane portable tankless water heater

Eccotemp L10 Portable Water Heater w/ Shower Set
  • Lightweight, easy to carry, and compact, makes using it for camping, hunting, in...
  • Runs on a standard 20 lb. Liquid Propane tank and is equipped with an electronic...
  • Features a safety shut-off that is activated when the unit runs longer than 20...

This is another portable water heater that is best for outdoor use. It is fueled by propane, and just like the other water heaters mentioned, it needs two D batteries for ignition. It is portable and can easily be transported from one place to another through its mounting bracket. It runs only when you need it to, and that is its edge over the other products.


  • With a gas regulator
  • Can cater 20-lb propane or more
  • Has a rain cap for added protection
  • With the common Half inch NPT fitting
  • Comes with an adapter and quick connects
  • With a 20 psi starting pressure and a pressurized input
  • Easy-to-reach screw holes at just ½ inch distance from the back


  • Heavy
  • Lacks handle
  • Does not include batteries
  • No temperature readout
  • No freeze protection for winter use
  • Does not have a shower head and hose
  • Continuous hot water usage lasts only for 20 minutes

Excel propane tankless water heater

Excel Tankless On-Demand Gas Water Heater VENTFREE – Propane (LPG) - Low Water Pressure Startup
  • "Low Water Pressure" Startup Technology
  • Starts with only 2 PSI of Water Pressure - Amazon Exclusive

If you are looking for a well-designed tankless water heater that uses propane gas, this one suits you. Its edge, among other models, is that it does not give off flue gas since it uses technology from excel, which converts combustion to water vapor and monoxide.

Just like other propane models, it also requires two D-cell batteries. It has a 2 psi starting temperature.


  • With a brass adaptor
  • With a ½” standard NPT fitting
  • The box includes batteries for immediate use
  • It can work well at high altitudes as high as 7000 ft
  • Has a wide range of water pressure from 2 to 120 psi
  • Environmentally friendly with its Excel proprietary technology


  • No freeze protection
  • Installation can be hard
  • Can only continuously work for 20 minutes
  • Can have difficulty functioning at 50 degrees above
  • Does not come with a shower head, hose, gas regulator and thermostat
  • Needs to be set up in a well-ventilated place because the top can get extra hot
  • The carbon monoxide it gives off can be dangerous at extreme levels, thus, requiring a detector.

EZ 202 portable propane tankless water heater

The same as the previous water heaters, this one also uses propane gas and requires two D-cell batteries for ignition. It is fuel efficient as it has a high flow rate of 3.2 gallons per minute, a higher one compared to other portable models.

In terms of fuel conservation, it has a winter/summer knob that enables propane usage limitations. The heater also automatically turns off once the temperature goes more than 88 degree Celsius or 190F.


  • Uses ½” NPT fittings
  • Steel-made gas inlet
  • 2.9 psi starting pressure
  • Has a thermostat readout
  • Has a shower head and hose
  • Has many vents for air passage
  • Brass-made outlet fittings and water inlet


  • Lacks gas regulator
  • No rain cap included
  • Does not include batteries
  • Does not come with a handle
  • Easily extinguished in windy areas
  • Installation and set-up can be difficult due to hard-to-reach top mounting brackets.

Girard 2GWHAM propane tankless water heater

Girard RV Tankless Hot Water Heater
  • POWERFUL PERFORMANCE — At 42,000 BTUs, this continuous hot water heater...
  • CONSISTENT TEMP — The onboard microprocessor monitors incoming cold water...
  • HIGHLY EFFICIENT — The Girard RV tankless water heater consumes half the LP...

This is an all-rounder, fit for all-season use, and is a stronger, quieter, and more high-performing version than the 1GWHAF model.  This propane-powered water heater does not need any special lines and has adaptors for brands like Suburban and Atwood.

However, it is not the ideal unit for portable use but is a reliable one for freezing weather. It also cannot go over 95 degrees.


  • Self-regulating
  • With freeze protection
  • Requires a 12V power source
  • With a ½” and ¾” water line and flare fitting, respectively
  • Comes with a digital controller to remotely adjust the temperature


  • Noisy cooling fan          
  • The cooling fan’s speed cannot be controlled
  • Does not come with a mounting equipment
  • Hot water continuously flows only for 20 minutes but can restart once turned off.

PrecisionTemp RV-550 tankless water heater           

This small and light water heater is the winner in terms of efficiency. With just 1.2 the size and 1/3 the weight of an average 10-gallon water heater, it is capable enough to compete with its larger counterparts. It uses propane as fuel and also comes with adapter mounts for ease of adjustment to varying heater compartments.

If you are a fan of customization, you can choose between raw metal finish door or a standard white color or even have it personalized at an additional cost. Even with its hefty price, it gives value for your money.


  • Does not produce a lot of noise
  • With an automatic freeze protection
  • Has a flow rate of 1.5 gallons per minute
  • Unlimited continuous hot water, compared to other models’ 20 minutes
  • With ½” and 3? 8” water line NPT fittings and gas line flare fitting, respectively


  • Expensive
  • No thermostat readout
  • No valve for water input control
  • Does not come with a controller
  • Takes time to get continuous water flow
  • It can be useless in areas with low and inconsistent water pressure
  • It May shut down when used in very cold temperatures, such as in less than 38C.

Camp chef HWD5 triton water heater

Just like the other products mentioned, this also uses two D cell batteries along with its propane gas fuel. It has around 25 psi starting pressure with an 80 psi maximum pressure, inferior to that of other products. It comes with a garden house adapter, and one of its edges among the other models is that it can easily produce hot water right away.


  • Has a stand
  • Easy-to-reach screw holes
  • ½” NPT fittings for water line
  • With a big handle for ease of carrying
  • Comes with a garden hose, shower head, and hose


  • No gas regulator
  • Lacks thermostat readout for monitoring
  • Flames easily get extinguished in windy areas
  • Does not have a drain plug for ease of draining and added winter protection
  • The continuous flow of 20 minutes and will not restart after turning the unit off.

Bosch E34 Tronic 3000& electric water heater

Bosch Electric Mini-Tank Water Heater Tronic 3000 T 4-Gallon (ES4) - Eliminate Time for Hot Water - Shelf, Wall or Floor Mounted
  • CONVENIENT HOT WATER HEATER: 4 gallon point-of-use mini-tank fits under your...
  • LONG LASTING QUALITY: This electric water heater is easy to maintain and has...
  • INDEPENDENT INSTALLATION: 36-37" cord plugs into a 120 volt outlet for...

This 13.65 x 13.5 x 13.75 inch Bosch mini electric tankless water heater is best for small RVs. Despite its size, it can handle 4 gallons of water. It has superior insulation and is resistant to corrosion because of its glass-lined tank interior.


  • 3-foot-long power cord included
  • Works in the standard 120-volt AC outlet
  • Has a temperature-and-pressure relief valve
  • With an external control dial for accurately changing temperatures


  • Electric element life may be short due to the small size

Tankless water heater: how does it work?

The water heater works by instantly heating the water that flows through it. The heated water then flows out through another line. Propane and electricity are used to run these tankless water heaters. The RV requires 12 volt DC power.

The most popular variants of water heaters are the mobile ones which can be used in or out of the RV. Unlike the traditional models, these tankless variants can instantly and consistently produce hot water, saving you from the cycle of having to constantly refill the water in the tank, heat it, and replace the water.

Different types of RV tankless water heaters

Gas water heater

This type is named after its power source, which is propane or kerosene. Since it is fueled by gas released through power vents, it requires proper ventilation to avoid health risks.

Moreover, it can also be bad for the environment as the propane-powered heater releases greenhouse gases. Its edge among the electric models is that it is cheaper and 85 percent more efficient.

Electric water heater

Unlike gas water heaters, electric water heaters are environmentally friendly because they do not emit greenhouse gases. It can even be installed with a solar panel or generator, and installing it is not a hassle-free experience.

Aside from that, this type gives value for your money as it is cost-effective with 99 percent efficiency, but efficiency can lessen when used in short bursts like hand washing.

Condensing water heater

These have 92 to 94 percent energy efficiency, relatively low compared to other types. This type utilizes a second heat exchanger, which recycles exhaust heat to further increase the water temperature. However, its edge is that it is cheaper compared to the other types.

Non-condensing water heater

Just like the condensing type, the non-condensing one is not that efficient regarding energy consumption. This type works by utilizing a heat exchanger, which requires stainless steel for the hot exhaust ventilation. This can lead to additional expense, but the great part is that it is reliable, durable, and can last long.

Is buying a tankless water heater worth it?

A tankless water heater makes hot water accessible to you as it instantly produces it whenever you need it. It is also more energy-efficient than other types as this utilizes 50% less propane.

For those with limited space, it also has less space consumption with the added benefit of lesser spillage risk.  However, it is undeniable that the initial price of the on-demand tankless water heater is relatively higher than buying a tank, but is the higher cost justifiable? Is it really worth it?

Here are some pros and cons to consider before buying a tankless water heater.


  • It can last for about 5-10 years longer
  • Some states offer tax credits or rebates
  • Has lesser repair and maintenance cost
  • Does not need a storage tank for winterizing
  • It saves you around 8-14% of energy according to


  • Unstable water temperature
  • More expensive in terms of the initial cost
  • Risk of water wastage when not properly installed
  • What to keep in mind before buying an RV water heater
  • Some models can keep continuous hot water flow for only 20 minutes

Factors to consider before you purchase a tankless RV water heater

You will be bombarded by a number of choices if you go to the store without planning the features and capabilities that you are looking for. Here are some of the considerations you should bear in mind before planning your trip to the shop to buy a water heater.


Choose a tankless water heater that complements your current heater. The same is true when separately buying a door for it.  Another consideration for size is your water usage.  An average water heater can supply 2-6 gallons per minute and would be absurd to pair with a 12-gallon tank, for instance.

As a general guide, showers and toilets use around 1-3 and ½ to 2 gallons of water per minute, respectively, whereas for a kitchen sink, you need around 1-2 gallons per minute.


Aside from the size, also consider the space that you currently have. Choose one that doesn’t take up much space. An added tip is to choose a lightweight water heater that is easy to transfer.

British Thermal Unit (BTU)

British Thermal Unit, more commonly known as BTU, is synonymous with a unit’s horsepower as it refers to how much power gas appliances consume. The higher the BTU rating, the faster it will be in heating water or reaching a high temperature. Most water heaters have an average of 30,000 to 50,000 BTUs per hour.

Flow rate (GPM) and water pressure (PSI)

Water pressure is usually indicated in product labels as PSI. PSI is derived from its computation which is pounds per square inch. A minimum PSI is required in order to aid the water heater ignition. However, compared to the PSI, what is more, important is the flow rate.

Flow rate, on the other hand, refers to the input flow rate that triggers burner ignition once a certain required or minimum level is reached. If the flow rate is too low, you will have difficulty igniting your water heater. Flow rate is commonly indicated on product labels as GPM, meaning gallons per minute.

If you are having issues with the flow rate, you can increase it by removing anything that restricts the water flow in your plumbing. You can also try to use only one water fixture at a time.


A water heater’s price usually costs around 500 to 1000 dollars. This is just an initial price and does not cover the installation expenses. You should strike a balance between durability, capabilities, and your budget before deciding on which model to buy. These are what to be expected in each price range:

Less than 200 dollars

Water heaters in this price range have lesser features and may have small capacities compared to their more expensive counterparts.

200 to 500 dollars

Most-bought water heaters usually fall within this price as these models are efficient without taking a huge toll on your budget.

500 dollars or higher

These premium tankless water heaters can go as expensive as 1000 dollars or more. This is best for off-grid living or small cabin usage.

Fool proofing

Choose a water heater that has some protective capabilities for longevity. Examples of foolproofing features and capabilities you should look for are: having a design that prevents voltage fluctuation and protection against extreme weather and textures.


If you are not sure what to choose, one good piece of advice is to go for a tested and proven brand in that industry. Atwood, Girard, and Suburban are known to be the leaders in the area of water heaters. These are also retrofitted, so you won’t have issues with compatibility. Here are some of the leading brands in the market today.


One of the best products from this brand is the Takagi Indoor Tankless Water Heater. You can trust this brand as it has been in the industry since 1952 and has a global office in Canada. It has regional offices in Tennessee, New Jersey, and California as well.


Established in 1947, Suburban one is 5 years older than Takagi. It started in Dayton, Tennessee, and is now a leading brand in manufacturing and supplying RV and water heating, and cooking appliances. One of its famous products is the Suburban Electric Ignition RV Water Heater.


This company is known for distributing the gasFlex flexible gas piping system. Its Excel tankless gas water heater lines are definitely worth checking out. This brand was established in 2004 and is based in Miami, Florida.

The Girard Group

The Girard Group released the first RV tankless water heater last 2009 and holds the title of being one of the best-selling products in the industry. Its 2GWHAM Tankless water heater is worth buying.

How to use the on-demand tankless water heater

Various models require different installation techniques. Another factor for this variation is the space where you were to install the unit. If you are not confident with the process, it is better to seek professional help.  However, if you have basic mechanical skills, you can do it yourself.

Just make sure to connect all water, gas, and electrical lines. Do not forget to securely mount the heater. Once it is installed, here are the steps that you should take.

  1. Inspect the bypass valve.
  2. Open the bypass valve and let water flow into the primary tank,
  3. Connect your RV to a water source.
  4. Begin pumping water; you may use an onboard pump.
  5. Turn on the hot water tap for water to flow towards the heating tanks like

Frequently asked questions

Can I convert the RV water heater to tankless?

Yes, you can, and it actually helps you save when it comes to heating costs. However, it needs careful planning—from picking the right heater, preparing the necessary tools, and computing the purchasing and installation costs.

You may also ask for professional help to prevent installation problems.

Is it okay to mount a tankless water heater under a sink or anywhere in my RV?

Putting your tankless water heater under a sink can be an attractive and space-saving measure. It is safe to do so as long as you check the manufacturer’s instructions to ensure no wires are jeopardized.

For lightweight water heaters, you can mount them on panel boards. Make sure that where you mount it is strong and sturdy enough to handle the heater, especially if you are mounting a heavier one. Your heater falling from its mount can lead to breaking and damage.

The water coming out of the faucet is colder than what is shown in the control panel. Is this normal?

As the water runs through your RV panel, it gets cooler than the intended temperature. The farther the fixture is from the heater, the colder it will be. You may get a few degrees of variation in temperature, and that is normal.

Can I directly connect the hot water side to the faucet, or should I use a shower head?

You can directly connect the hot water to the faucet, but using a shower aid is the advisable choice. However, if your RV has a feature for cold and hot settings, you can assure that you’ll have access to both hot and cold water.

Do I need to clean my tankless water heater?

Different manufacturers have varying instructions on how often you should clean your water heater. It is best to double-check this in your owner’s manual.

Do I need to buy a water pump for my tankless water heater?

It depends on your RV. You can save money if you buy a tankless water heater without a pump if you have an existing motorhome with a fully functional water pump.

If you have a small travel trailer or a pop-up camper, you may need to have a water pump to maximize your heater’s flow rate.

Most manufacturers do not sell water pumps along with the water heater. You can just connect it to a 12-volt electric water pump. If this seems like a hassle for you, you can watch out for water heaters with a free water pump.


Those are the guides we collated to make it easier for you to choose a tankless water heater amidst the wide array of choices in the market. Just remember, if you are not gifted in the mechanical area, better ask for help from a professional in installing your unit.

That is extra caution and extra savings on your part because you might end up destroying your unit without properly connecting the lines.

If you click on the Amazon link or Add to Cart and make a purchase, we earn a commission at no additional cost to you. Last Update: 2023-03-21