Hot water is a luxury of RV camping. It’s easy to take for granted when you haven’t camped in a tent for a while—but you will notice immediately if your water heater stops working. Whether you’re replacing a broken unit or considering an upgrade to an RV tankless water heater, you must know the advantages and disadvantages of this water heater type.
In this article, we’ll discuss the pros and cons of tankless water heaters, offer a buying guide to help you choose a compatible replacement, and suggest the top water heater brands that offer tankless models.
Key Takeaways
- Pros & Cons of Tankless RV Water Heaters: Tankless water heaters provide continuous hot water, improved energy efficiency, and longer lifespan, but they lead to increased water usage before heating, they only run on propane, and they may require complex retrofitting.
- Key Buying Considerations: When choosing a model, factor in water usage, installation compatibility, winterization needs, and cost. Tankless heaters require proper ventilation, and propane-powered models are the most practical for RVs.
- Top Brands & Recommendations: Leading RV tankless water heater brands include Suburban, Girard, Furrion, Fogatti, and Dometic, with portable options from Excel, Eccotemp, and Marey. Compatibility, power source, and safety features should guide your choice.
What Is a Tankless Water Heater (and How Does it Work?)
Traditional RV water heaters have a tank that fills with water, either from your fresh water tank or a city water connection. That water is heated using a propane burner, an electric heating element, or both. Depending on usage, these heaters can have a 30-minute recovery rate, meaning how long you must wait for the tank to refill and the water to heat before using it in sinks or the shower.
Tankless water heaters, also known as on-demand water heaters, work a little differently. They don’t have a traditional container to store and heat water. When you open a hot water fixture, cold water runs through a heat exchanger powered by propane gas. This design allows them to deliver constant hot water without the delay of heating a larger quantity of water in a tank.
RV Tankless Water Heater Pros and Cons
Here are a few of the advantages of tankless RV water heaters:
- Increased energy efficiency because there’s no heat loss from standing water.
- Reduced risk of spillage and decreased potential for RV water damage.
- No waiting for your water heater’s tank to heat up.
- Longer life expectancy than standard water heaters.
While they’re a great option, some RVers still swear by standard water heaters because tankless RV water heaters can:
- Cause you to waste a lot of water before hot water is dispensed.
- Only operate on propane gas.
- Require complex retrofitting if you don’t do your research to find a compatible model.
Many newer tankless models have worked out the original kinks related to water consumption and energy usage, but it’s worth knowing about these potential downsides when deciding if an RV tankless water heater is right for you.
How To Choose a Tankless RV Water Heater
Before getting enamored with the idea of hot water on demand, consider these important buying factors:
Water Usage
When choosing a regular water heater, consider how often you might use these appliances in one day. With a tankless water heater for an RV, the more important question is how often you might use multiple appliances simultaneously.
Estimate your water usage before shopping for a tankless water heater for RV use. Here is a quick reference for the average water consumption of RV appliances:
- Toilet: ~0.8 gallons per flush
- Bathtub: ~2-4 gallons per minute
- Shower: ~1.5-3 gallons per minute
- Kitchen Sink: ~0.5 gallons per minute
- Dishwasher: ~4-6 gallons per cycle
- Washer: ~8-20 gallons per load
Tankless water heaters can provide an on-demand water heating capacity from 1.5 to 6 gallons per minute, depending on the model. Compare and contrast models to meet your water usage demands.
Installation
One benefit of upgrading to a tankless water heater is the size. These units typically require less space than traditional models. However, you still need to ensure compatibility. Some models can be retrofitted in the same space that housed your old water heater. This is the simplest solution, and many manufacturers offer retrofit kits to help with a safe, aesthetically pleasing installation.
You may want to schedule a service appointment for this upgrade because you’ll need to safely disconnect propane and shut off your electricity to install an RV propane tankless water heater.
Technician Tip: Service technicians will ensure proper installation location and adherence to all codes and regulations regarding proper water heater ventilation. If you occasionally RV in locations that drop below 32℉, ask your RV performance specialist about installing an antifreeze kit with your new tankless water heater.
Winterizing
Speaking of freezing temperatures, the process of winterizing your RV changes slightly if you upgrade from a standard water heater to a tankless model. A basic winterizing process uses air to blow out water lines, but a small amount of water will always remain.
That water will destroy a tankless water heater if temperatures drop below 32℉. If you have a tankless heater or hydronic heating system, you must blow air out of water lines and add RV-safe antifreeze. We recommend choosing the Delux Winterize package, available at any Camping World Service Center.
That package requires pumping RV antifreeze through your entire fresh water system to displace water and protect everything from freeze damage. This invaluable preventative measure is well worth the investment. Additionally, when retrofitting a tankless model, remove the bypass valves on your standard water heater. These valves serve no purpose for a tankless design and can sometimes lead to confusion if you’re winterizing your RV at home.
Electric or Gas? Is There Even a Choice?
Many standard water heaters can use LP gas or an electric heating element. For example, models using a 1,400-watt electric heating element produce around 6,000 BTUs of heat per hour (BTUs are British Thermal Units).
To deliver comparable performance, a tankless water heater powered by electricity would require a minimum of 40,000 BTUs per hour, which equates to roughly 75 amps of 120 VAC power. That far surpasses the 30 or 50 amps standard on most RVs, and that’s why tankless heaters restrict you to propane-only operation, whether boondocking or plugged into a power pedestal.
More typical in camper vans, there are hydronic heating systems that deliver hot water through an electric heating method. However, as currently designed, most electric tankless water heaters would require 220 volts of AC power, which surpasses the capability of most RVs.
Your best option is a propane tankless water heater for your RV equipped with a small battery bank. That battery bank provides the ignition source when you aren’t plugged into 120 VAC power. Many RVers also find LP tankless water heaters easier to install and don’t mind replacing or refilling RV propane containers regularly.
There are portable tankless water heaters that operate on 120 VAC power. However, these models typically only deliver a water temperature up to about 95℉ and offer a low flow rate of 0.5 gallons per minute, which wouldn’t be effective in an RV.
Design
The best tankless RV water heaters are generally simpler to maintain than water heaters that rely on a pilot light or direct spark ignition (DSI). When purchasing a tankless water heater, choose one with a display you can operate.
You also need to ensure compatibility with your existing systems. If you’re replacing a broken heater, sticking with the previous manufacturer is an easy path. Contact that manufacturer to acquire a compatible Girard RV tankless water heater, Suburban tankless RV water heater, Furrion RV tankless water heater, or another from your preferred manufacturer.
For those with camper vans or any other RV that doesn’t have an existing water heater to replace, portable tankless water heaters can be a viable solution for luxurious outdoor showers on a warm summer afternoon.
Cost
Some tankless water heaters for RVs are more affordable than traditional models, but you may spend more to replace an old water heater than you’d spend to repair it.
If you’re set on upgrading, factor in the potential long-term savings of a tankless RV water heater. These energy-efficient units can reduce your overall energy costs compared to replacing your old heater with a standard DSI water heater.
If your standard RV water heater isn’t functioning, start by learning more about troubleshooting water heaters or schedule an appointment to have issues diagnosed by a certified RV technician.
What Is the Best RV Tankless Water Heater?
For those committed to going tankless, some of our favorite brands include Suburban, Girard, Furrion, Fogatti, and Dometic. If you want a quick solution using a portable model, you’ll find some of the best options from Excel, Eccotemp, and Marey.
The best tankless water heater for your RV depends on compatibility, ease of installation, water usage, and winterization concerns. Of course, you must weigh those factors against the heater’s cost and any additional costs of retrofitting your camper to safely provide hot water using a tankless heater.
Consider additional factors like the required power source, indoor versus outdoor use, and safety features like oxygen depletion safety shut-off.
Whether you’re trying to avoid family fights over who showers next or want to be more energy efficient, a tankless heater is the future of instantaneous hot water for RVers. Here are a few other resources to help you upgrade your RV:
- Do You Need a Water Pressure Regulator for RV?
- Tankless Water Heater Winterization Guide
- Best RV Upgrades
- Should You Upgrade RV Batteries?
Do you have a tankless water heater for your RV? Share your experience in the comments below!
I am doing a lot of research to find a tankless water heater for my 2021 Mallard M26 travel trailer. My current 6 gal Atwood gas/ electric water heater has a water leak that can’t be fixed. I am on shore power and my camper uses 120v/30 amps with a 15 amp breaker for the Atwood/Dometic water heater. My biggest concern with switching to a tankless propane water heater is the electrical part. I want to make sure my camper can handle a tankless wh. I called Camping World in Lincoln, Ne and they said that I could. I gave them all the info of my Atwood/Dometic heater and they said they would call me back once they found a tankless water heater that would coincide with my travel trailer but I never got a call-back. I tried 3 more times to call the guy back but couldn’t reach him. I don’t know what happened with that attempt to locate a tankless so I’m asking for some guidance this way. I’ve researched what my current water heater requires using the model no. Then I go online to research the tankless water heaters and the information is not clear probably because I am not that knowledgeable about electricity. Most tankless say they need 12v of DC, 55,000 BTU, and so on but there is nothing that says 120 v/30 amps of shore power for example and nor does it say that a tankless needs a certain breaker circuit of 15 or more amps. I need some help on finding the most compatible tankless water heater for my Mallard travel trailer. I would really, really appreciate any advice or a list of options. I’ve been online for several days in the past 3 months taking notes, comparing the different types of tankless wh’s and I’m never sure of which one is the right one.
Hi Kathy!
We appreciate this feedback and we are always looking for ways to improve. Can you please email our corporate customer service team at cs****@ca**********.com so that they can look into this experience?
Why don’t you list the physical size . Very important
Hi Neal!
Good call. Folks should certainly consider whether a tankless model will fit in their RV without requiring a significant renovation.
Thanks for pointing that out.
I wish the article would go further into the difference between propane, 110volt, 120volt, 208volt, and 240volt. I have a 30Amp 5th wheel and what I am finding out is 110v or 120volt is not enough to take a shower with, let alone rinsing soap out of my wife’s long hair. That is the problem I am having with my 6gal tank. I see people complaining about the time it takes to get hot water and how much water it uses. I have found Truma on demand hot water heater to be a hybrid with instant hot water, they also offer a combination hot water heater/furnace. I am still looking for a solution. If I go tankless, I will probably loose the ability to use shore power to heat my hot water. I’m thinking about getting a 120v and plumbing it into the inlet of the 6gal water heater & use it when I have shore power.
Atwood tankless in my 2014 newmar needed a $5 reset switch. Atwood said no longer available, no longer made. 4 yr old water heater and cant get simple part. Atwoods answer to my problem , “buy a new water heater “.
To anyone reading this reply, Len has probably moved on, but he did not mention whether or not he looked into the possibility of using another manufacturer’s switch. This may not be possible, if it’s a unique part, but on many other appliances, there are substitutes for some of the parts that can be used safely. Just takes some research.
Good point here! There’s always the chance of finding a replacement part, but it takes research to find something that’s truly “form, fit, and function-compatible” right out of the box. And even when you find something that’s advertised as such, don’t be surprised if it takes a little additional work to make it fit and operate with your RV, especially if it’s an older model and the original part has been discontinued. The original part manufacturer is still your best resource for finding the original part or acquiring a part number for a compatible replacement!
Stay away from Atwood
Since the cost of a whole house is very expensive I am put smaller ones on each area of water usage
except the washer (Cold water) in the RV some with 4 g/m are 140 dollars and easy to connect if you are handy with tools
My water heater is rather old, so I’ve been thinking about getting a new one. Thanks for pointing out that the place one lives will determine whether electric or gas hookups are less expensive. Do you have any tips for deciding which size of water heater one needs for their family.
http://www.moodyplumbing.com/residential-water-heaters
I also live in my 5th wheel n my electric/propane water heater went out. This was two years ago. Purchased a Girrard tankless on demand water heater. Not only has this given me hot water in less than ten seconds but you can believe this or not.. l have a two hundred gal. portable hot tub n can fill it up without running out of hot water! I’m not kidding man!
I have park model 50 amp with double 20 breaker for current water heater, can I put in a on demand water heater?
Hi Nancy!
I’d recommend contacting our Performance and Improvements department. They’ll likely have some more specific questions about your RV’s year, make, and model to help you determine if you’re able to install a tankless water heater and, if so, which heater models might be compatible. You can find their contact info here: https://rv.campingworld.com/rv-performance-improvements
Hope that helps!
I was wondering ( I live in a 5th wheel) if a portable hot water heater can be put in an RV to keep water hot for showers? Or what would be best and cheapest? I’m not goin to do it now but maybe in the future. Thanks
What kind of cost is there to purchase and change to this system we now have a 6 gal and it’s never enough
I agree with most of what you have said. Also, I’m glad you mentioned that tank-less water heaters are much smaller and have less risk of spillage. Great blog, thanks for sharing this!
I’m glad you mentioned that tankless water heaters are much smaller and have less risk of spillage. My husband and I have been thinking about getting a new water heater, but we don’t have the room for a bigger one. I like how a tankless water heater would be smaller and could fit in the space we have. Thank you for the information!
I agree completely with Jason B. Our new 2015 class c motor home came with a tankless (we call it thankless) water heater. When taking a shower, the water temperature varies from bone chilling to scalding. there is no way to keep a constant reasonable temperature. We have tried many suggestions, and tips from several sources over the last 2 plus years but to no avail. Our previous 2 motor homes had the standard tank type water heaters. We never had a problem with excessive propane or water usage. This RV has a full body paint scheme and we will have an additional step in matching the replacement access panel to the outside when replacing this hated device.
What are the possibilities of a combination solar/propane for my fifth-wheel. I’m considering a similar unit to replace the gas water heater in my home.
I would encourage anyone interested in a tankless water heater for their RV to do a lot of research. My new (2015) motorhome came with a tankless water heater. My wife and I both hated it. I replaced that tankless with a good old-fashiioned 6-gallon tank type, and now we’re both happy again. I understand now that the newer tankless water heaters have some of the issues worked out, but even so, you will very likely waste more water with a tankless, thereby filling the gray tank faster, and use more electricity also. If your off the grid, and have a small RV, water management is much more important than saving the propane it takes to heat up your tank water heater.
Tankless are fine, but there is a major problem – they waste water. It takes a considerable volume of water before the hot water is dispensed. If you are dry camping this wasted water could become a serious problem. We have one but I am not sure I would replace it if it failed.
Where are most tankless water heaters installed & how are gas lines run to & attached?
Great information to have on the front-end of the purchase of a tankless water heater. I’ve been considering this purchase for some time and this information proved valuable in determining type and size, as well as accessory equipment (had never heard or been informed of anti-freeze kits in previous research).
Thank you
I installed mine outside my food truck and just ran I line to the propane tank already on board with shut off valves. Water was easy. They come with hoses. I hooked one up in my driveway to my house Hose and propane tank to check. Worked great. I could shower in driveway. Didn’t but could have
Amen, just got a new rv with thankless Girard, hate it, wastes all sorts of water to get hot every time you interrupt the flow
Thanks for info, Len.
Hi Len,
Appreciate the comment. Could you elaborate as to why? What has your experience been like?
Thanks!
How is this , because if it is installed in the same placement as tank type it still travels through the same lenth of pipe, and it is heated at the same point, so something must not be working correctly.