An outdoor shower is a game-changer. It turns a simple rinse into an experience, connecting you with nature after a swim, a workout, or a day in the garden. But that experience hinges on one critical component: a reliable source of hot water. Cold showers have their place, but for daily comfort, you need a dedicated tankless (on-demand) water heater designed for the elements.
Choosing the right unit isn’t just about picking the shiniest box. You’re balancing performance, installation logistics, and your specific climate. Do you need an electric on-demand water heater or is a propane water heater better for your setup? What about cold weather performance? We’ll cut through the noise. For many installations, especially those requiring robust power and smart controls, professionals often point to the NEW Rinnai RX199iN. It’s a top-tier exterior water heater known for its efficiency and consistent output, making it a solid benchmark as we explore your options.
Top Electric Water Heater Models for Outdoor Showers
Not all outdoor shower heaters are created equal. The best models are built to withstand moisture, temperature swings, and provide instant hot water on demand. Heres a look at the primary types and some standout examples.
Tankless Electric: The On-Demand Standard
These are the most popular choice for a permanent outdoor shower setup. They heat water directly as it flows through the unit, providing endless hot water and saving space. The key specs to watch are flow rate (GPM) and electrical requirements (voltage/amperage).
- EcoSmart ECO 11: A classic for a reason. This 13kW model can deliver about 1.3-1.5 GPM, enough for a standard showerhead. It’s compact and relatively straightforward to install if you have the requisite 240V electrical line.
- Stiebel Eltron Tempra 24 Plus: Steps up with advanced flow control to maintain temperature even if water pressure fluctuates. A great choice for areas with inconsistent water supply.
- Rheem RTEX-13: Offers reliable performance with simple digital controls. Rheem’s build quality is consistently good, and this model is a workhorse for outdoor applications.
Portable & Point-of-Use Options
For a temporary setup, a rental property, or an outdoor shower kit you want to move around, portable units shine. They often plug into a standard 120V outlet and may use a small tank or on-demand heating.
- Camplux 1.32 GPM Outdoor Shower Heater: A popular portable water heater that runs on propane, highlighting the electric vs propane water heater for outdoor shower debate. Propane offers more heating power portably, but electric is often simpler for permanent installs.
- Zodi Outback Gear Hot Shower: A fully self-contained, battery-powered pump system. It’s more for camping but proves the versatility of the shower water heater category.
Key Features to Compare
Looking at specs sheets can be dizzying. Focus on these four critical areas to narrow down the best electric tankless water heater for outdoor shower use.
Performance Metrics: GPM, kW, and Temperature Rise
This is the heart of the matter. Flow rate (GPM) tells you how much hot water you get. Temperature rise is how many degrees the heater can warm the incoming water. A higher kW rating means more heating power. For a comfortable shower in most climates, you’ll want a unit that can deliver at least 1.5 GPM with a 40-50F temperature rise.
Durability & Environmental Protection
Your heater will face rain, sun, and possibly freezing temps. Look for:
- Freeze protection: An absolute must in any climate that dips below freezing. This feature automatically activates heating elements or a drip function to prevent internal ice damage.
- IP (Ingress Protection) Rating: A rating like IP25 means it’s protected against low-pressure water jets from any direction. The higher the second number, the better.
- Corrosion-resistant casing: Powder-coated or stainless steel finishes are ideal.
Ease of Installation & Control
Consider the wiring, mounting, and how you’ll operate it. Simple dial controls are reliable. Digital displays offer precise temperature settings. Some smart models, like certain navien or Rinnai units, offer Wi-Fi controlhandy for pre-heating the shower from inside the house.
Installation Guide & Considerations
Figuring out how to install an electric water heater for outdoor shower is a major step. While a licensed electrician is non-negotiable for the hardwiring, understanding the process helps you plan.
Pre-Installation Planning
Answer these questions first:
- What size electric water heater do I need for an outdoor shower? Match the unit’s GPM to your showerhead’s flow. A low-flow head (1.5 GPM) pairs with a smaller heater than a rainfall head (2.5 GPM).
- Electrical Supply: Most electric tankless units require a dedicated 240V circuit. Check your panel’s capacity.
- Location: Mount the heater close to the shower point to minimize heat loss in the pipes, but protected from direct spray unless its rating allows it.
- Shower head compatibility: Ensure your chosen showerhead’s flow rate doesn’t exceed the heater’s capacity, or you’ll get lukewarm water.
Step-by-Step Installation Overview
Always follow the manufacturer’s manual and local codes. This is a general outline:
- Shut off power and water. This is your first and most important step.
- Mount the unit securely to a stable exterior wall using the provided bracket.
- Run the necessary electrical conduit and water supply lines (PEX or copper) to the unit. This is the electrician and plumber’s main work.
- Connect the water lines (cold in, hot out) using appropriate fittings.
- The electrician will connect the unit to the dedicated circuit.
- Before sealing everything, flush the unit and check for leaks. Then power it on and test the temperature output.
For comprehensive energy efficiency tips that apply to all water heating, the DOE’s authority guide is an excellent external resource.
Maintenance Tips & FAQ
A little upkeep goes a long way in extending the life of your outdoor shower heater.
Simple Routine Maintenance
- Annual Descaling: Even with good water, mineral buildup happens. Follow the manual’s procedure to flush the heat exchanger with a vinegar solution. This is the single best thing you can do for longevity.
- Visual Inspection: Every few months, check for leaks, corrosion, or debris blocking the vents or water inlet filter.
- Winterization: If you live in a freezing climate and won’t use the shower, you must drain and shut off the heater. Rely on its freeze protection only for unexpected cold snaps during the season of use.
Frequently Asked Questions
Can I use my indoor tankless heater for the outdoor shower?
Technically yes, if it has the capacity. But it’s inefficient. You’ll waste water and energy waiting for hot water to travel through long pipes. A dedicated exterior water heater is almost always the better solution.
Why is my electric tankless not getting hot enough?
Usually, it’s one of three things: the incoming water is colder than expected (winter), the flow rate (GPM) is too high for the unit’s power, or the unit is scaled up and needs descaling. Check your showerhead’s flow first.
Is propane really better than electric for outdoors?
It has a higher BTU output per dollar, making it powerful and often cheaper to run, especially for high-flow showers. But it requires venting, a gas line, and dealing with propane tanks. Electric is cleaner, often easier to install, and perfectly sufficient for most single-shower applications.
The perfect outdoor shower heater is the one you don’t have to think about. It just works, delivering instant hot water reliably season after season. Your choice ultimately boils down to your climate, your shower habits, and your home’s existing infrastructure. Prioritize freeze protection and proper sizing. Get the electrical done right the first time. Then, all that’s left is to enjoy the upgrade. Your future self, stepping into a warm shower under the open sky, will thank you.
