Outdoor electric tankless water heaters can provide hot water on demand without storing a large tank. They can work well for outdoor showers, pool areas, cabins, workshops, and other spaces that need hot water close to the point of use. Electric models also avoid combustion gases and gas venting, but outdoor installation requires careful attention to weather protection and electrical safety.
The right heater should match your water flow and temperature needs. Power rating matters because higher-kilowatt models can heat more water as it flows through the unit. You should also check the required voltage, amperage, circuit size, flow rate, and temperature rise before buying. Outdoor placement needs extra care because not every electric tankless heater has a weatherproof enclosure. A suitable outdoor-rated housing and installation that follows local electrical codes may be necessary for some models.
This guide covers six of the best outdoor electric tankless water heaters for different uses, water demands, and budgets. We considered heating power, flow rate, temperature control, electrical requirements, outdoor suitability, installation, size, and overall value. These picks can help you find an on-demand water heater that fits your outdoor setup without taking up the space required by a traditional storage tank.
6 Best Outdoor Electric Tankless Water Heaters
| Image | Title | Best For | Link |
|---|---|---|---|
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Tankless 110V Electric Water Heater | Best overall for compact, instant hot water needs. | View on Amazon |
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APUS Propane Tankless Water Heater | Best for high-capacity, whole-home outdoor use. | View on Amazon |
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Rheem RTG Propane Tankless Heater | Best budget-friendly, high-efficiency unit. | View on Amazon |
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APUS 27kW Electric Tankless Heater | Best for whole-house 240V electric efficiency. | View on Amazon |
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Rheem RTG Natural Gas Heater | Best for high-flow, large family residential setups. | View on Amazon |
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Upgraded 110V Electric Tankless Heater | Best portable solution for RVs and small kitchens. | View on Amazon |
Our Top 6 Best Outdoor Electric Tankless Water Heaters Reviews â Expert Tested & Recommended
1. Tankless 110V Electric Water Heater
This 110V, 3500W unit is a powerhouse for its size, providing instant hot water whenever you need it. It is built to last with high-quality stainless steel and aluminum components, making it a reliable choice for small spaces.
Key Features That Stand Out
- â Durable 304 stainless steel heating pipes
- â Fast-acting instant heat technology
- â Clear LED display for temperature monitoring
- â Energy-saving design that only heats what you use
Why We Recommend It
We love this heater because it simplifies the installation process for smaller setups. The combination of safety features and its efficient heating capacity makes it a smart investment for anyone looking to save space and energy.
Best For
Perfect for home bathrooms, small kitchen sinks, or commercial barber shops requiring point-of-use heating.
Pros and Cons at a Glance
2. APUS Propane Tankless Water Heater
The APUS propane tankless water heater is a high-performance beast, delivering 190,000 BTU of power. It is ideal for those who need consistent, high-volume hot water for a whole home or large outdoor application.
Key Features That Stand Out
- â High output of 8.1 GPM
- â Smart app-controlled temperature settings
- â Compact design for easy outdoor mounting
- â Wide temperature range (95°Fâ149°F)
Why We Recommend It
This unit is incredibly convenient thanks to the smart app connectivity, allowing you to control your water temp from anywhere. It combines industrial-grade performance with a sleek, space-saving outdoor form factor.
Best For
Best suited for larger residential homes or multi-bathroom setups that require a continuous supply of hot water.
Pros and Cons at a Glance
3. Rheem RTG Propane Tankless Heater
The Rheem RTG Series is a fantastic value for anyone looking to save on energy bills. It provides great performance with 160,000 BTU, making it one of the most efficient options for large households.
Key Features That Stand Out
- â 0.82 Uniform Energy Factor (UEF)
- â Endless, on-demand hot water supply
- â Significant energy cost savings
- â Robust build quality for outdoor durability
Why We Recommend It
We recommend the Rheem for its reliability and energy efficiency. It is a workhorse that saves up to 34% on energy costs compared to older electric tank models, paying for itself over time.
Best For
Best for large families and multi-bathroom homes that need a budget-conscious, high-efficiency upgrade.
Pros and Cons at a Glance
4. APUS 27kW Electric Tankless Heater
If you prefer electricity over gas, this 27kW unit is a fantastic choice for whole-house applications. It uses self-modulating technology to keep water at your exact desired temperature without wasting electricity.
Key Features That Stand Out
- â Massive 27kW heating capacity
- â 1-degree temperature increment adjustments
- â Self-modulating power output
- â Memory function for saved settings
Why We Recommend It
The precision controls make this unit stand out. It ensures your shower water is exactly the heat you want, every single time, with no standby losses.
Best For
Excellent for modern, all-electric homes that need high flow rates for multiple showers.
Pros and Cons at a Glance
5. Rheem RTG Natural Gas Heater
For those with natural gas lines, this Rheem RTG series unit is a powerful, high-efficiency solution. It offers a robust 8.4 GPM, perfect for larger families who are tired of running out of hot water.
Key Features That Stand Out
- â High output of 8.4 GPM
- â Powerful 180,000 BTU input
- â Energy-efficient performance
- â Designed specifically for outdoor installation
Why We Recommend It
The high flow rate makes this one of the most reliable units for demanding households. It is a proven system that minimizes energy waste significantly compared to standard tank heaters.
Best For
Ideal for active families and large homes with multiple bathrooms and high simultaneous water demand.
Pros and Cons at a Glance
6. Upgraded 110V Electric Tankless Heater
This upgraded 110V unit is the ultimate portable solution for RVs, tiny homes, and camping. It offers safety and convenience in a tiny, easy-to-install package.
Key Features That Stand Out
- â Instant hot water with no preheating
- â IPX4 waterproof rating for safety
- â Lightweight and compact footprint
- â Dry-burn and leakage protection
Why We Recommend It
It is specifically built for life on the road. The safety features make it ideal for non-traditional living spaces where reliable equipment is a must.
Best For
Best for RV enthusiasts, small kitchens, and temporary setups needing a portable hot water source.
Pros and Cons at a Glance
Complete Buying Guide for Best Outdoor Electric Tankless Water Heaters
Essential Factors We Consider
When choosing the best outdoor electric tankless water heater, prioritize flow rate (GPM) and temperature rise. Think about how many faucets you will use at the same time. If you live in a colder climate, look for a higher temperature rise capability so your water stays warm even during winter.
Budget Planning
While the initial cost of a tankless system might be higher than a traditional heater, you save significantly on energy bills over time. Factor in the cost of professional installation to ensure your plumbing and electrical/gas lines are up to code and safe for outdoor use.
Final Thoughts
Choosing the right heater is about matching your household’s peak demand with the unit’s power. Whether you need a small unit for an RV or a high-efficiency system for a full home, there is a perfect option above that balances performance with durability.
Frequently Asked Questions
Q: Do these units work in freezing weather?
A: Most outdoor units are designed with freeze protection, but it is important to check the specific model rating. In extreme cold, some users choose to add a small heat source or shelter the unit.
Q: Can I install these myself?
A: While smaller 110V units are often simple enough for experienced DIYers, gas and 240V electric models usually require professional installation to ensure safety and code compliance.
Q: How long do these heaters typically last?
A: With proper maintenance and regular cleaning, tankless water heaters can last 20 years or more, significantly outlasting traditional storage tanks.