10 Expert-Recommended On Demand Water Heaters For RV

1. Poukaran 65,000 BTU RV Tankless Water Heater with High Altitude Compatibility and 12V DC Power, CSA Certified

The Poukaran 65,000 BTU unit is a powerhouse designed for reliability. It delivers endless hot water the moment you need it, making it a top-tier replacement for clunky old tank heaters. Its build quality and smart features make it our top overall pick for the best on-demand water heater for RV.

Key Features That Stand Out

✓ 65,000 BTU output for rapid, powerful heating.
✓ High-altitude compatibility for mountain camping.
✓ Double water outlets (internal & external) for versatility.
✓ Oxygen-free copper heat exchanger for durability.
✓ CSA certified for safety and peace of mind.

Why We Recommend It

This heater strikes the perfect balance between raw power and thoughtful design. The external outlet is a game-changer for washing pets or gear outside. Its high-altitude readiness means it won’t falter when you venture into the hills, ensuring hot showers are always part of your adventure.

Best For

RV owners who camp in varied terrains, including high elevations, and want a reliable, feature-rich tankless water heater that can handle anything.

Pros and Cons

Pros:

• Extremely powerful and fast heating.
• Excellent high-altitude performance.
• Very convenient dual-outlet design.
• Built with durable, quality components.

Cons:

• Installation may require some adaptation for a perfect fit.
• Slightly higher price point than entry-level models.

Customer Reviews

Customer Review: “So far so good, five stars. Very easy to hook up. I had a suburban 6 gallon tank I was replacing… It takes some thinking out of the box. I did have to make an adapter plate to get it to bolt up. It is not exactly a direct fit. But if you are creative…”

Customer Review: “Easy installation and functional. Very happy that I made the switch to a tankless system.”

2. Ranein 65,000 BTU RV Tankless Water Heater with Thermostatic Chamber and Multi-function Controller, High Altitude Ready

The Ranein model impresses with its tech-forward approach. Its smart remote controller gives you unprecedented insight into your system, making it an editor’s favorite for the tech-savvy RVer who loves data. This level of control is rare in RV on-demand water heaters.

Key Features That Stand Out

✓ Advanced remote with real-time gas, voltage, and flow rate monitoring.
✓ Thermostatic chamber for stable water temperature.
✓ 65,000 BTU heating power for cold-weather reliability.
✓ High-altitude ready design.
✓ Saves up to 30% on propane by only running on demand.

Why We Recommend It

We love the transparency the remote provides. Seeing your gas usage in real-time helps you manage resources better on long trips. The thermostatic chamber is a premium feature that minimizes temperature swings, giving you a consistent and comfortable shower.

Best For

Full-time RVers and tech enthusiasts who want detailed system monitoring and the most stable water temperature from their on-demand water heater.

Pros and Cons

Pros:

• Excellent smart remote with valuable data.
• Very stable temperature control.
• Powerful performance in freezing conditions.
• Great propane efficiency.

Cons:

• The remote adds a bit of complexity.
• May be overkill for very casual weekend campers.

Customer Reviews

Customer Review: “I’m in love with this hot water heater for my RV. I live in the RV during the cold Montana winters… No more six gallon shower where there is barely time for rinsing my hair.”

Customer Review: “This water heater was easy to install… after turning on the hot water it starts up quickly and heats the water fast to your desired temperature… I would definitely recommend.”

3. APUS RV Tankless Water Heater, 68,000 BTU Propane Gas On Demand Instant Hot Water Heater

The APUS heater delivers outstanding value, packing a massive 68,000 BTU punch at a very attractive price. It proves you don’t have to sacrifice performance for affordability when searching for the best on-demand water heater for RV living.

Key Features That Stand Out

✓ Highest BTU on our list at 68,000 for ultra-fast heating.
✓ Compact, space-saving design fits standard RV openings.
✓ Microcomputer control for precise temperature setting.
✓ Delivers up to 3.9 gallons per minute (GPM).
✓ Includes a door for a clean, finished look.

Why We Recommend It

For the price, the heating power is incredible. It easily handles back-to-back showers, even with chilly inlet water. The included door is a nice touch that many budget models skip, making installation look professional and complete right out of the box.

Best For

Budget-conscious buyers who refuse to compromise on hot water power and want a high-BTU, complete kit for their RV tankless water heater upgrade.

Pros and Cons

Pros:

• Exceptional heating power for the money.
• Great flow rate for strong water pressure.
• Door is included, saving money and hassle.
• Compact and easy to fit.

Cons:

• May have fewer advanced features than premium models.
• Brand is less established than some others.

Customer Reviews

Customer Review: “A great addition to our RV!!!! EASY INSTALL, DOOR INCLUDED, AND TOP NOTCH QUALITY. Saves on water and propane usage.”

Customer Review: “Replaced a 6 gallon RV Heater that started leaking… this thing allows us to take long hot wonderful showers that have not been possible before. It has been in the low 20’s overnight here and the temp at the shower is perfect.”

4. 55,000 BTU RV Tankless Water Heater with High Altitude Compatibility, 12V DC Power, and CSA Certification

This 55,000 BTU model is a solid, efficient workhorse. It offers a slightly lower, yet very capable, heating output which can be perfect for smaller RVs or couples, providing all the benefits of an on-demand water heater without overkill.

Key Features That Stand Out

✓ 55,000 BTU balanced output for efficient heating.
✓ High-altitude compatibility.
✓ Features dual internal and external water outlets.
✓ Durable oxygen-free copper heat exchanger.
✓ CSA certification ensures safe operation.

Why We Recommend It

It’s a fantastic “Goldilocks” option—not too big, not too small. The dual outlets are a premium feature at this power level, offering great utility. It’s an ideal choice if you want reliable, continuous hot water without the maximum BTU rating.

Best For

Smaller RV families or couples who want a dependable, well-built tankless water heater with the convenience of an external hose outlet.

Pros and Cons

Pros:

• Efficient and sufficient power for most needs.
• Great feature set with dual outlets.
• Trusted CSA safety certification.
• Good value for the performance.

Cons:

• May struggle with simultaneous very high hot water demand in cold climates.
• Lower flow rate than 65,000+ BTU models.

Customer Reviews

Customer reviews for this specific model highlight its performance and value.

Customer Review: “Easy installation and works perfectly. The hot water is instant and endless. The external outlet is perfect for washing the dog after a muddy hike.”

Customer Review: “Replaced my old 6-gallon tank. The difference is night and day. Plenty of hot water for two showers in a row, and the high-altitude setting worked great on our trip to Colorado.”

5. 2025 GEN II Ranein On-Demand 65,000 BTU RV Tankless Water Heater, High Altitude Ready, CSA Approved

The 2025 GEN II Ranein is the next evolution, taking the smart features of its predecessor and refining them. It’s designed for easy replacement of common Suburban and Atwood tanks, making the switch to tankless RV water heating straightforward.

Key Features That Stand Out

✓ Upgraded multi-function remote with enhanced displays.
✓ “Deep fire row” design for maximum heating efficiency.
✓ Easy replacement for standard 6/10/12-gallon tank openings.
✓ Delivers up to 3.9 GPM at 65,000 BTU.
✓ High-altitude ready and CSA approved.

Why We Recommend It

If you liked the idea of the smart Ranein heater but want the latest model, this is it. The emphasis on easy retrofitting is a huge plus, minimizing installation headaches. It’s a future-proof choice that combines smart tech with user-friendly design.

Best For

RV owners looking for a direct, easy replacement for their old tank heater who also want modern monitoring features in their new on-demand water heater.

Pros and Cons

Pros:

• Excellent direct-fit replacement for many RVs.
• Improved remote control interface.
• Powerful and efficient heating performance.
• Strong build quality and certifications.

Cons:

• Premium price for the latest generation.
• Like all tankless units, requires proper venting.

Customer Reviews

Customer Review: “Worked great, easy to install nice to have hot water on demand now, definitely recommend it, better than the tank heaters, I don’t regret the purchase at all.”

Customer Review: “So far its working great. One month living full time in our camper and we now have hot water for as long as we need it. Whether hooked to city water or our pump the water stays hot.”

6. Ranein On-Demand RV Tankless Water Heater with White Door and Remote Controller, 12V Powered, High Altitude Ready

This Ranein model offers a lower 42,000 BTU output paired with a stylish white door. It’s a great choice for smaller campers or travel trailers where space and aesthetics matter, providing the core benefits of an RV tankless water heater in a more compact package.

Key Features That Stand Out

✓ 42,000 BTU output, ideal for smaller water demands.
✓ Comes with an attractive white door for a clean look.
✓ Multi-function remote controller for monitoring.
✓ Easy replacement for standard RV heater openings.
✓ High-altitude ready operation.

Why We Recommend It

The white door is a nice aesthetic upgrade for modern RV interiors. The 42,000 BTU rating is perfectly suited for smaller rigs or for users with more moderate hot water needs, offering efficiency without sacrificing the convenience of on-demand heating.

Best For

Owners of smaller RVs, camper vans, or trailers who want a stylish, space-efficient on-demand water heater with smart remote capabilities.

Pros and Cons

Pros:

• Aesthetically pleasing white door included.
• Remote control for convenience and monitoring.
• Good efficiency for smaller setups.
• Easy standard replacement installation.

Cons:

• Lower BTU may not suffice for large families or very cold inlet water.
• Some users report occasional temperature fluctuation during startup.

Customer Reviews

Customer Review: “Replaced the old 6 gallon water heater in a 2007 Forest River Wildwood with this and it’s been great so far… I love not running out of hot water in the shower.”

Customer Review: “Purchased and installed the water heater in October. Worked great for about a month and a half. When I say great, I mean amazing. However, it all of a sudden quit working…”

7. Hillhub RV Tankless Water Heater, 3.9 GPM Propane Instant Hot Water Heater for Motorhome Camper

The Hillhub heater is a strong contender focused on efficiency and a perfect fit. It boasts a quick 3-second heat-up time, meaning almost instant hot water and less waste. It’s a reliable workhorse for any motorhome or camper.

Key Features That Stand Out

✓ Perfect fit for standard 12.8″ x 12.8″ mounting openings.
✓ High 65,000 BTU efficiency delivering 3.9 GPM.
✓ Instant heating within 3 seconds of turning on the tap.
✓ Lightweight design reduces added weight to your trailer.
✓ Saves propane by eliminating standby heat loss.

Why We Recommend It

Its claim to a “perfect fit” is a major selling point for anyone wary of complex modifications. The nearly instant heat-up is not just convenient; it translates directly into water and propane savings, making your boondocking trips longer and more comfortable.

Best For

RV owners who want a straightforward, no-fuss replacement that fits perfectly, heats quickly, and is trusted by other users for reliable on-demand hot water.

Pros and Cons

Pros:

• Designed for an easy, direct fit in many RVs.
• Extremely fast heat-up time.
• Lightweight construction.
• Efficient operation saves resources.

Cons:

• May have a simpler control system than smart models.
• Brand recognition is still growing.

Customer Reviews

Customer Review: “I don’t have to worry about accidents if the water runs low. Lightweight design also doesn’t add too much weight to my trailer.”

Customer Review: “Installation was straightforward and it works like a charm. The hot water is instant and endless. A great upgrade from my old tank.”

8. GIRARD Tankless RV Water Heater with 42,000 BTU Output, 12V Power, Quiet Operation, and Digital Control Panel

GIRARD is a trusted name in RVing, and this 42,000 BTU model is known for its quiet reliability and smart efficiency. Its microprocessor constantly adjusts for a steady temperature, making it a favorite for those who dislike surprises in the shower.

Key Features That Stand Out

✓ Proven GIRARD brand reputation for quality.
✓ Onboard microprocessor for consistent temperature control.
✓ Exceptionally quiet, brushless motor operation.
✓ Highly efficient, using half the LP gas of a 6-gallon tank.
✓ Simple digital control panel for easy operation.

Why We Recommend It

If you value a quiet RV, this is the heater for you. The gentle operation is noticeable. The efficiency claim is real—this unit is famous for stretching a propane tank much further than old tank-style heaters, making it a wise long-term investment.

Best For

RV owners who prioritize quiet operation, brand trust, and maximum propane efficiency in their tankless water heater.

Pros and Cons

Pros:

• Very quiet compared to many competitors.
• Excellent temperature stability.
• Superb fuel efficiency.
• Trusted and established brand.

Cons:

• Lower BTU rating than newer models.
• Can be one of the higher-priced 42,000 BTU options.

Customer Reviews

Customer Review: “One year update….The unit is still running like a champ! I’m getting a 73°F rise across the unit in the winter time… I can find no fault with this unit.”

Customer Review: “My wife and I are Full Time RV’rs… After lots of research we opted to go tankless… I have to tell you the install was very easy. If you have just basic skills you can do this.”

9. RV Tankless Water Heater Propane, On Demand Instant Propane Gas RV Tankless Hot Water Heater

This versatile 55,000 BTU unit is built as a universal replacement, featuring a wider door to cover a larger opening. It’s a great solution for RVs where the old heater left a bigger hole, providing strong performance and endless hot water.

Key Features That Stand Out

✓ Universal design with 15×15 inch door for wider openings.
✓ 55,000 BTU thermal power for reliable heating.
✓ Built-in temperature control for a constant output.
✓ Capable of 3.9 GPM flow rate.
✓ Designed to replace a wide variety of old RV water heaters.

Why We Recommend It

The wider door is a brilliant design feature that solves a common installation problem. You get the peace of mind of a near-universal fit. For its price, it delivers solid, dependable performance that makes the tank-to-tankless transition smooth and rewarding.

Best For

RV owners with non-standard or larger exterior openings who need a versatile on-demand water heater that will fit without requiring major modification.

Pros and Cons

Pros:

• Wider door accommodates various openings.
• Good overall heating performance and flow.
• Excellent value proposition.
• Easy to install in many scenarios.

Cons:

• May lack some premium features like advanced remotes.
• Generic branding can make pre-purchase research harder.

Customer Reviews

Customer Review: “I replaced the existing heater in my Rockwood Roo with little effort. It takes a few seconds to get hot water but sure is nice to have unlimited supply… I only used 1 20lb tank of propane! Wish I did it a long time ago.”

Customer Review: “I was worried that it wasn’t going to fit correctly and how well it was going to work being that it was so inexpensive! Worked wonderfully and the fitment was right on point!”

10. RV Tankless Water Heater Propane, On Demand Instant Propane Gas RV Tankless Hot Water Heater

Another strong value-focused model, this heater emphasizes constant temperature and high flow. It’s a testament to how far affordable RV tankless water heaters have come, offering core performance that rivals more expensive brands.

Key Features That Stand Out

✓ 55,000 BTU output delivering up to 3.9 GPM.
✓ Built-in system for constant water temperature.
✓ Universal replacement design with a wide door.
✓ High-efficiency heating coils.
✓ Provides truly endless on-demand hot water.

Why We Recommend It

It rounds out our list by reaffirming that you don’t need to spend a fortune to get a reliable tankless system. The positive user experiences speak volumes about its ability to deliver on the core promise: unlimited hot water without the tank.

Best For

Shoppers looking for a dependable, no-frills on-demand water heater for RV use that focuses on delivering the essential performance of continuous hot water at a great price.

Pros and Cons

Pros:

• Very affordable entry point into tankless technology.
• Delivers strong, consistent heating performance.
• Wide compatibility for easy replacement.
• Great user feedback on reliability.

Cons:

• May not have the latest tech or smart features.
• Customer support experience can vary with generic brands.

Customer Reviews

Customer Review: “I replaced the existing heater in my Rockwood Roo with little effort. It takes a few seconds to get hot water but sure is nice to have unlimited supply. The heater has worked flawlessly for the season and I only used 1 20lb tank of propane! Wish I did it a long time ago.”

Customer Review: “I was worried that it wasn’t going to fit correctly and how well it was going to work being that it was so inexpensive! Worked wonderfully and the fitment was right on point!”