You pull into a scenic campsite after a long day of driving, and you’re looking forward to a hot shower. You turn on the faucet, but the water is lukewarm at best, and within minutes it’s cold. This is the classic RV water heater problem: a limited tank that runs out just when you need it most. If you’re tired of rationing showers and waiting for the tank to reheat, it’s time to consider a tankless water heater for your RV.
In this guide, we’ll explore the best electric tankless water heaters for RVs, along with a top propane option, to help you choose the right one for your travel lifestyle. We’ll cover key features, installation considerations, and what to look for in a unit that fits your rig. For more background, check out our top electric tankless water heater brands for 2026.
Buying Guide: What to Consider for Your RV
Power Source: Electric or Propane?
Your RV’s existing water heater setup often dictates the easiest upgrade path. If you have a propane hookup and want maximum hot water flow, a propane tankless unit like the ORBEK RV Tankless Water Heater, Propane, 12V DC is a strong choice. It delivers continuous hot water with a 60,000 BTU burner, and it runs on 12V DC, which is perfect for off-grid boondocking.
On the other hand, if you want a simpler installation without propane lines, an electric tankless water heater might be the way to go. However, you’ll need to check your RV’s electrical capacity. A unit like the Rheem 11kW Multi Fixture Tankless Electric Water requires a 240V connection and a 50-amp breaker, which may not be available in all RVs. Many smaller electric units, such as the Tankless Small Water Heater Electric 120V 29.2Amp, run on standard 120V, but they have lower flow rates.
Flow Rate and Temperature Rise
Flow rate, measured in gallons per minute (GPM), tells you how much hot water the unit can produce at a given temperature rise. In an RV, you typically need at least 1.5 GPM for a comfortable shower. Electric tankless heaters often have lower flow rates, especially the 110V models. For example, the 110V Tankless Water Heater Electric is designed for point-of-use applications like a sink, not a full shower.
Consider your climate: if you camp in cold areas, the incoming water temperature is lower, so you’ll need a higher temperature rise. The Rheem 11kW can raise the temperature by up to 60°F at 2.68 GPM, which is sufficient for most RV use in moderate climates. For more on choosing the right size, read our best electric tankless water heater reviews.
Installation and Space
Space is at a premium in an RV. Tankless water heaters are compact and can be installed in tight spaces, but you need to consider the mounting orientation and clearances. Some units, like the Tankless Small Water Heater Electric 120V 29.2Amp, are designed for under-sink installation and are only 7.9″ x 6.4″ x 2.5″. Others, like the ORBEK, are designed to fit standard RV water heater openings (15″ x 15″, 15″ x 18″, 18″ x 18″).
Check the electrical requirements: most electric tankless units require a dedicated circuit and hardwiring. The 110V unit from xwdzswgs requires a 32A breaker and 2.5mm² wire, which is a common requirement for such devices. If you’re not comfortable with electrical work, consider hiring a professional or choosing a propane model that only needs a 12V connection.
Final Thoughts
When choosing the best electric tankless water heater for your RV, think about your primary use: if you need a full shower and have propane available, the ORBEK RV Tankless Water Heater, Propane, 12V DC is an excellent choice with its high-altitude performance and remote control. If you prefer an electric option and have a 240V system, the Rheem 11kW Multi Fixture Tankless Electric Water offers reliable performance for multiple fixtures. For smaller tasks like washing dishes at a sink, the 120V models are ideal. Whichever you choose, you’ll enjoy endless hot water on your adventures.
Frequently Asked Questions
Can I install an electric tankless water heater in my RV?
Yes, but you must verify your RV’s electrical system. Most RVs have 120V or 240V connections. For 120V units, you’ll need a dedicated circuit with a 32A breaker. For 240V units like the Rheem, you’ll need a 50-amp double-pole breaker and a compatible service panel. Always consult a professional if you’re unsure.
What size tankless water heater do I need for an RV?
The size depends on your hot water demand. For a shower, you’ll need at least 1.5 GPM. If you only need hot water for a sink, a point-of-use unit with 0.4-0.66 GPM is sufficient. Consider the temperature rise needed based on your climate.
Are tankless water heaters more energy-efficient for RVs?
Yes, tankless water heaters only heat water when you need it, eliminating standby heat loss. This can save energy and propane compared to traditional tank heaters. For example, the ORBEK’s burner operates only when hot water is requested, reducing fuel consumption.
Can I use a 110V tankless water heater for a shower in my RV?
Most 110V units have low flow rates, around 0.5 GPM, which is not enough for a comfortable shower. They are best for point-of-use applications like a bathroom sink. For a shower, look for a 240V electric unit or a propane model like the ORBEK. For more tips, see our best propane tankless hot water heater guide.
