Best Outdoor Tankless Water Heaters: 15 Spec-Based Picks
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Finding the best outdoor tankless water heaters requires looking at published specs rather than marketing claims. We compared 15 models to help you choose based on flow rate, fuel type, and physical dimensions. The Camplux 5L Portable Propane Water Heater leads this list because its 10-pound weight and 1.32 GPM flow rate support off-grid camping and low-pressure washing needs. All picks rely strictly on the specifications published on the listings. This guide helps you decide which unit fits your outdoor space and power constraints.
Quick picks
The best fit for you
- You need the lightest portable unit for camping Ranein 6L Portable Propane Water Heater The Ranein model weighs 9.92 pounds, making it the lightest option for easy transport.
- You want whole-house heating with indoor remote control VEVOR 5.3 Gal Outdoor Propane Tankless Heater The VEVOR unit includes a 32.8-foot wired remote for managing temperature settings from inside.
- You require high-volume hot water for a large home APUS 190,000 BTU Outdoor Natural Gas Water Heater The APUS heater delivers 8.1 GPM using natural gas for substantial household output.
- You need a robust non-condensing unit for multiple fixtures Rinnai 6.1 GPM Outdoor Propane Water Heater The Rinnai RE160eP provides up to 6.1 GPM across five fixtures with dedicated outdoor operation.
Our 15 picks
Camplux 5L Portable Propane Water Heater
Best for: off-grid camping and low-pressure outdoor washing
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 1.32 GPM
- Certification
- CSA
- Dimensions
- 4.33 x 11.4 x 14.8 inches
- Use
- Camping, RV
This outdoor propane water heater delivers 1.32 gallons per minute and weighs 10 pounds for easy transport. It runs on liquid propane and requires two D-cell batteries for ignition, eliminating the need for an electrical outlet. Operating with water pressure as low as 3.0 PSI, it pairs with low-pressure pumps or gravity setups. It suits you if you need portable hot water for camping, washing gear, or off-grid outdoor cabins.
Pros
- Operates on water pressure as low as 3.0 PSI
- Requires no electrical outlet using two D-battery ignition
- Weighs 10 pounds with an integrated folding handle
- Includes shower head, 5-foot gas regulator, and connection hoses
Cons
- Output capacity limited to 1.32 GPM for single-point use
- Requires periodic D-battery replacements for ignition
- Restricted strictly to outdoor installation
Good fit if
- You need a lightweight outdoor water heater for camping or RV trips.
- You rely on gravity-fed water bags or low-pressure pumps operating down to 3.0 PSI.
- You lack access to grid electricity and need battery-powered ignition.
Skip if
- You need more than 1.32 GPM to run multiple hot water fixtures simultaneously.
- You require a permanent indoor residential water heating setup.
- You plan to run your water heater on a natural gas supply.
Verdict: Camplux 1.32 GPM Portable Propane Water Heater delivers off-grid hot water at low operating pressures in a 10-pound package. It gives you an independent outdoor washing setup without requiring standard electrical power.
Camplux 2.11 GPM Portable Outdoor Propane Water Heater
Best for: portable off-grid camping and outdoor washing
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 2.11 GPM
- BTU
- 55,000 BTU/hr
- Temperature Control
- 18-95 °F
- Certification
- CSA
View on Amazon: Camplux 2.11 GPM Portable Outdoor Propane Water Heater
This outdoor propane water heater delivers up to 2.11 GPM with a 55,000 BTU maximum output. It runs on a standard 20-pound liquid propane tank and uses two D-cell batteries for electronic ignition, requiring no electrical outlet. With a starting water pressure requirement of 3.6 PSI, it suits you if you need portable hot water for camping, washing gear, or off-grid outdoor chores.
Pros
- Delivers up to 2.11 GPM with a 55,000 BTU/hr heat rating
- Operates off-grid using two D-cell batteries for ignition
- Ignites at water pressure as low as 3.6 PSI
- Includes a 5-foot shower head, gas regulator, and garden hose adapter
Cons
- Maximum listed temperature reaches 95 °F
- Requires manual draining via the bottom stem to prevent cold-weather freeze damage
Good fit if
- You need off-grid hot water powered by a 20-pound propane tank and D batteries.
- You have low-pressure water sources down to 3.6 PSI for outdoor showers or washing.
- You want an outdoor package that includes a regulator, hose adapter, and shower head.
Skip if
- You require water temperatures above the listed 95 °F limit.
- You need a natural gas connection instead of portable propane tanks.
- You plan to install your water heater indoors.
Verdict: Camplux 2.11 GPM Portable Propane Water Heater provides battery-ignited hot water with low starting pressure requirements and bundled hookup accessories. It serves outdoor off-grid needs well for remote cabins, campsites, and washing stations.
Ranein 8.5 GPM Outdoor Propane Water Heater
Best for: High-flow outdoor propane needs
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 8.5 GPM
- BTU
- 190,000 BTU
- Dimensions
- 24.3 x 15.1 x 8.1 in
- Weight
- 44 pounds
This Ranein unit delivers 8.5 GPM at 190,000 BTU for outdoor propane use. Its compact 24.3 x 15.1 x 8.1 inch frame fits tight spaces. The integrated blower adjusts to wind pressure for stable combustion. Anti-freeze protection safeguards internal components. It supports 4-6 outlets, making it suitable for whole-family hot water needs in suitable climates.
Pros
- High 8.5 GPM flow rate
- 190,000 BTU heating capacity
- Integrated wind-adjusting blower
- Anti-freeze protection included
Cons
- Not recommended for altitudes over 2,000 feet
- Requires manual draining of pressure relief valve in cold weather if unused
- 44-pound weight requires sturdy mounting
Good fit if
- You need high flow for multiple simultaneous outlets
- You have a standard outdoor propane setup
- You want built-in wind protection for the burner
Skip if
- You live above 2,000 feet elevation
- You need natural gas compatibility
- You require a compact unit under 20 pounds
Verdict: Ranein 8.5 GPM Propane Outdoor Heater provides substantial hot water volume for large households, provided you are below 2,000 feet elevation and can secure its 44-pound frame.
VEVOR 5.3 Gal Outdoor Propane Tankless Heater
Best for: whole-house outdoor propane water heating
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- BTU
- 120,000 BTU/h
- Temperature Control
- ±1°F
- Dimensions
- 23.2 x 15 x 15 inches
- Use
- Whole House
View on Amazon: VEVOR 5.3 Gal Outdoor Propane Tankless Heater
This outdoor propane tankless water heater delivers up to 5.3 gallons of hot water with a heat output of 120,000 BTU/h. Designed for whole-house use, it mounts outside and connects using standard 3/4-inch NPT fittings. You get precise temperature management within 1 degree Fahrenheit using an included 32.8-foot wired control panel. It fits homes needing high-capacity outdoor propane heating without bringing gas lines inside.
Pros
- Delivers 120,000 BTU/h heat output with 5.3 gallons capacity
- Maintains water temperature within ±1°F of setting
- Includes a 32.8-foot wired remote control panel
- Uses standard 3/4-inch NPT plumbing connectors
Cons
- Requires routing a 32.8-foot wire to control temperatures from inside
- Large physical profile measuring 23.2 by 15 by 15 inches
Good fit if
- You need a whole-house propane water heater installed outdoors.
- You want remote temperature adjustment via a 32.8-foot wired panel.
- You have standard 3/4-inch NPT plumbing connections.
Skip if
- You need an ultra-compact portable water heater for camping.
- You require a natural gas model rather than liquid propane.
Verdict: VEVOR 5.3 Gal Outdoor Propane Water Heater provides 120,000 BTU/h of whole-house heating with ±1°F temperature control. Its 32.8-foot wired remote lets you manage outdoor temperature settings from indoors.
Camplux 6L Portable Propane Water Heater
Best for: portable outdoor camping showers
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 1.58 GPM
- BTU
- 41,000 BTU/hr
- Temperature Control
- 50°F to 122°F
- Dimensions
- 17.3 x 5.12 x 11.8 inches
The Camplux 6L Portable Propane Water Heater is an outdoor on-demand unit built for camping, cabins, and RV setups. It delivers up to 1.58 GPM using a 41,000 BTU/hr propane burner and supports a temperature rise from 50°F to 122°F. Operating on two D batteries without an electrical hookup, it suits you if you need a lightweight, handle-equipped system for off-grid rinsing.
Pros
- Supplies up to 1.58 GPM with 41,000 BTU/hr propane heat
- Includes 5-foot gas regulator and 5-foot shower kit
- Adjustable 50°F to 122°F temperature rise with LED display
- Carrying handle on a compact 14-pound frame
Cons
- Requires two D batteries that are not included
- Water inlet hose and propane tank must be supplied separately
- Requires an external pump when drawing from water tanks
Good fit if
- You need a portable propane water heater for camping, RVs, or remote cabins.
- You want an included regulator and shower kit for fast outdoor setup.
Skip if
- You require more than 1.58 GPM to supply multiple plumbing fixtures at once.
- You use natural gas rather than liquid propane tanks.
Verdict: Camplux 6L Portable Propane Water Heater delivers 41,000 BTU/hr of on-demand outdoor heat with an included shower kit. Its 14-pound frame and battery-driven ignition make it a capable single-point heating solution away from standard hookups.
Ranein 6L Portable Propane Water Heater
Best for: camping and portable outdoor showers
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 1.58 GPM
- Dimensions
- 11.4 × 11.4 × 19.2 inches
- Weight
- 9.92 pounds
The Ranein 6L is a compact propane tankless water heater designed for outdoor use. It delivers 1.58 GPM at 41,000 BTU with a low water pressure start-up of 3.6 PSI. The unit weighs 9.92 pounds and includes a hanging chain for tree mounting. It features a 6-in-1 safety system and brass construction. This model suits campers or RV users needing portable, on-demand hot water for showers or pet bathing.
Pros
- 1.58 GPM flow rate with 41,000 BTU heating power
- Low water pressure start-up at 3.6 PSI
- Includes hanging chain and mounting bracket for tree installation
- 6-in-1 safety system with auto-shutoff at 176°F
- Lightweight 9.92-pound design for easy portability
Cons
- Lower flow rate of 1.58 GPM compared to higher-capacity models
- Limited temperature range of 55.4°F to 109.4°F
- No remote control or digital display for precise adjustments
Good fit if
- You need a lightweight unit for camping or RV trips
- You want a heater that starts at low water pressure
- You prefer propane fuel for outdoor use
Skip if
- You require high flow rates for multiple fixtures
- You need precise temperature control beyond 109.4°F
- You prefer natural gas over propane
Verdict: Ranein 6L Propane Outdoor Heater is a practical choice for campers needing portable hot water. It fits users prioritizing easy setup and safety features over high flow rates.
APUS 190,000 BTU Outdoor Natural Gas Water Heater
Best for: large homes using outdoor natural gas lines
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Natural Gas
- Flow Rate
- 8.1 GPM
- BTU
- 190,000 BTU
- Voltage
- 120V AC
- Temperature Control
- 95°F–149°F, ±1°F
View on Amazon: APUS 190,000 BTU Outdoor Natural Gas Water Heater
The APUS 190,000 BTU Outdoor Natural Gas Water Heater is an exterior-mounted tankless unit engineered for high-demand residential use. It delivers up to 8.1 GPM of hot water, supporting five to six fixtures simultaneously with an activation flow rate of 0.79 GPM. Powered by 120V AC, it includes standard 3/4-inch plumbing connections and mobile app control. This model suits you if you need whole-home outdoor capacity running on natural gas.
Pros
- High flow capacity of up to 8.1 GPM powered by 190,000 BTU
- Supports remote adjustments via the Tuya app and wired controller
- Low minimum activation flow rate of 0.79 GPM
- Standard 3/4-inch gas and water connections
Cons
- Requires an outdoor 120V AC electrical power source
- Coverage limited to a 2-year component warranty
Good fit if
- You need up to 8.1 GPM to supply multiple fixtures simultaneously.
- You have a dedicated outdoor natural gas supply and a 120V AC outlet.
Skip if
- You require a propane-fueled heater rather than natural gas.
- You lack access to an outdoor 120V AC electrical connection.
Verdict: APUS 190,000 BTU Outdoor Natural Gas Water Heater supplies high-volume hot water for multiple fixtures using natural gas and outdoor 120V power. Its 8.1 GPM capacity and digital controls make it a capable exterior whole-home option.
Ranein 18L Outdoor Propane Tankless Water Heater
Best for: outdoor showers and low-pressure areas
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 4.74 GPM
- BTU
- 85,300 BTU
- Temperature Control
- 55.4°F to 109.4°F
- Dimensions
- 24 x 7.1 x 13.8 inches
View on Amazon: Ranein 18L Outdoor Propane Tankless Water Heater
This Ranein 18L unit delivers 4.74 GPM of hot water using propane. It features an 85,300 BTU heating capacity and operates within a 55.4°F to 109.4°F range. The compact design measures 24 x 7.1 x 13.8 inches and weighs 20.7 lbs. It works with low water pressure starting at 3.6 PSI. This model suits outdoor spaces like yards or campsites where on-demand heating is needed.
Pros
- High flow rate of 4.74 GPM for steady hot water
- Operates at a minimum water pressure of 3.6 PSI
- Compact dimensions of 24 x 7.1 x 13.8 inches
- Includes 6 advanced safety protections
Cons
- Lower heating capacity than higher-end models on this list
- Temperature range caps at 109.4°F
- Requires well-ventilated outdoor installation only
Good fit if
- You need a high flow rate for outdoor showers
- You have low water pressure in your rural area
- You want a lightweight unit for portable use
Skip if
- You require indoor installation
- You need water temperatures above 109.4°F
- You want a higher BTU output for large homes
Verdict: Ranein 18L Propane Outdoor Heater provides strong flow for outdoor tasks but lacks the high heat output needed for whole-house use. It is best for campers or those with low water pressure who need reliable hot water on demand.
Rinnai 6.1 GPM Outdoor Propane Water Heater
Best for: outdoor propane setups running multiple fixtures
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 6.1 GPM
- Dimensions
- 24.6 x 14.1 x 10.8 in
- Venting Type
- Non-Condensing
- Weight
- 49.2 pounds
This Rinnai RE160eP is a non-condensing outdoor propane tankless water heater engineered for permanent exterior mounting. Delivering up to 6.1 GPM, it supplies hot water for up to five fixtures simultaneously. The unit features an LED screen for error codes and service reminders. It suits you if you need a dedicated propane supply outside your home with up to 15 years of heat exchanger warranty coverage.
Pros
- Delivers up to 6.1 GPM to supply hot water for up to five fixtures at once
- Built-in LED screen provides diagnostic error codes and service reminders
- Offers up to 15-year heat exchanger and 5-year parts warranty coverage
- Compact outdoor casing measuring 24.6 by 14.1 by 10.8 inches
Cons
- Requires optional Controlr module for WiFi operation
- Weighs 49.2 pounds and manufacturer advises professional installation
- Labor warranty drops from 5 years to 1 year if not registered within 90 days
Good fit if
- You need an outdoor propane heater capable of supplying up to five fixtures at once.
- You want an integrated LED display that shows service reminders and error codes.
- You plan to register the unit within 90 days of installation to maximize labor warranty.
Skip if
- You require out-of-the-box WiFi control without buying additional hardware.
- You plan to install your water heater indoors or connect it to natural gas.
Verdict: Rinnai RE160eP Outdoor Propane Water Heater provides up to 6.1 GPM across five fixtures with dedicated outdoor non-condensing operation. It offers robust long-term warranty protection when professionally installed and registered within 90 days.
Camplux 1.32 GPM Portable Propane Heater
Best for: lightweight off-grid outdoor showers
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 1.32 GPM
- Certification
- CSA
- Dimensions
- 14.8 x 4.33 x 11.4 inches
- Weight
- 10 pounds
This portable outdoor water heater runs on propane and delivers up to 1.32 GPM of hot water. At 10 pounds with a folding carry handle, you can move it easily for outdoor use. It ignites with two D-cell batteries and operates on water pressure as low as 3.0 PSI. If you need a lightweight, low-flow hot water setup for off-grid outdoor showers or washing gear, this unit fits your requirements.
Pros
- Weighs 10 pounds with a folding handle for transport
- Activates at a low water pressure of 3.0 PSI
- Powered by two D batteries without grid electricity
- Includes a 5-foot shower head, gas regulator, and garden hose set
Cons
- Maximum output is limited to 1.32 GPM
- Requires replacement D batteries to maintain ignition
Good fit if
- You need a lightweight 10-pound heater for mobile outdoor use.
- You operate with low water pressure down to 3.0 PSI off-grid.
- You want a complete propane setup with included shower head and regulator.
Skip if
- You need higher output than 1.32 GPM for multiple fixtures.
- You require a natural gas connection instead of propane.
Verdict: Camplux 1.32 GPM Portable Outdoor Propane Water Heater provides compact, battery-ignited water heating for low-pressure off-grid use. Its 10-pound frame and included shower attachments make it an efficient option for single outdoor tasks.
Westinghouse 8.1 GPM Propane Outdoor Heater
Best for: Whole-home outdoor hot water supply
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 8.1 GPM
- BTU
- 180,000 BTU
- Voltage
- 120V AC
- Temperature Control
- ±1°F
This outdoor propane tankless water heater delivers 8.1 GPM and 180,000 BTU. It supports three to five fixtures at once. The unit maintains temperature within ±1°F using self-modulating technology. A wired digital controller allows adjustment from 95°F to 158°F. It features freeze protection and CSA certification for year-round outdoor use. You get precise heating without standby loss.
Pros
- 8.1 GPM flow rate for whole-home use
- 180,000 BTU output power
- ±1°F temperature stability
- Integrated freeze protection
- CSA certified for safety
Cons
- Requires 120V AC power connection
- Wired controller limits remote placement
- 42-pound weight adds installation effort
Good fit if
- You need hot water for multiple simultaneous fixtures
- You want precise temperature control during showers
- You need freeze protection for outdoor use
Skip if
- You prefer natural gas over propane
- You want a portable unit for camping
- You need wireless remote control access
Verdict: Westinghouse 8.1 GPM Outdoor Propane Heater provides reliable whole-home hot water with precise temperature control. It suits homeowners who need high flow rates and durable outdoor performance with freeze protection.
NOVIEEX 5.3 GPM Outdoor Propane Tankless Water Heater
Best for: outdoor propane setups under 2,000 feet
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 5.3 GPM
- BTU
- 120,000 BTU
- Voltage
- 110V-120V AC/60Hz
- Temperature Control
- 95°F–149°F, ±1°F
View on Amazon: NOVIEEX 5.3 GPM Outdoor Propane Tankless Water Heater
The Novieex 5.3 GPM Outdoor Propane Tankless Water Heater mounts on exterior walls without indoor venting. It delivers up to 5.3 GPM using a 120,000 BTU propane burner and standard 3/4-inch NPT connections. It runs on a 110V–120V power supply to support its digital controls and active anti-freeze system. This unit fits your household if you need whole-home outdoor hot water for two to four fixtures simultaneously.
Pros
- Delivers up to 5.3 GPM with 120,000 BTU heating capacity
- Precise temperature adjustment from 95°F to 149°F within 1°F
- Standard 3/4-inch NPT connections for water and gas lines
- Built-in electric freeze protection and wind-resistant forced exhaust
Cons
- Not recommended for installations above 2,000 feet elevation
- Requires a 110V–120V AC electrical outlet for operation
- Requires manual draining below 41°F during extended non-use
Good fit if
- You live below 2,000 feet elevation and run propane fuel
- You want to feed two to four fixtures from an exterior wall
- You have an outdoor 110V–120V electrical outlet nearby
Skip if
- You live at an altitude higher than 2,000 feet
- You lack access to a 110V–120V electrical connection outdoors
- You use natural gas rather than liquid propane
Verdict: Novieex 5.3 GPM Outdoor Propane Tankless Water Heater delivers 120,000 BTU heating power with tight digital temperature stability for multi-fixture outdoor setups below 2,000 feet elevation.
GASLAND 2.64 GPM Portable Outdoor Propane Water Heater
Best for: camping, RVs, and compact outdoor spaces
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 2.64 GPM
- BTU
- 68,000 BTU/hr
- Certification
- CSA
- Dimensions
- 13 x 5.9 x 18.5 inches
View on Amazon: GASLAND 2.64 GPM Portable Outdoor Propane Water Heater
The GASLAND G10 is a compact outdoor propane water heater with a 2.64 GPM flow rate and 68,000 BTU output. Its slim 13 x 5.9 x 18.5 inch profile fits tight spaces. The unit uses a battery-powered electronic ignition and includes a CSA-certified regulator. You get a splash-proof design for light rain and a foldable handle for easy storage. It runs on a standard 20-pound propane tank.
Pros
- Compact 13 x 5.9 x 18.5 inch footprint
- 2.64 GPM flow rate for quick heating
- 68,000 BTU/hr power output
- Foldable and sliding handle for portability
- CSA certified gas regulator and hose included
Cons
- Lower 2.64 GPM flow rate limits simultaneous use
- Requires 2 D batteries for electronic ignition
- Not designed for prolonged rain exposure
Good fit if
- You need a compact unit for tight outdoor spaces
- You want a lightweight heater for camping or RVs
- You prefer battery-powered electronic ignition
Skip if
- You need a flow rate above 2.64 GPM
- You want a permanently installed outdoor unit
- You need a unit that withstands heavy rain
Verdict: The GASLAND G10 Outdoor Propane Heater is a practical pick for campers and RVers who need a lightweight, compact solution. Its slim design and moderate flow rate make it ideal for solo use or small tasks like washing pets or cleaning vehicles.
Camplux 2.64 GPM Portable Propane Water Heater
Best for: camping and RV showers
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 2.64 GPM
- Certification
- CSA
- Dimensions
- 12.9 x 5.9 x 18.5 in
- Use
- Camping, RV
View on Amazon: Camplux 2.64 GPM Portable Propane Water Heater
The Camplux F10 is a portable propane tankless water heater designed for outdoor use. It delivers 2.64 GPM with instant hot water. The unit weighs 15 lbs and measures 12.9 x 5.9 x 18.5 inches. It features an LCD display and a 2-in-1 control knob. CSA certification ensures safe operation. This compact model suits campers and RV users needing reliable hot water on the go.
Pros
- 2.64 GPM flow rate for comfortable showers
- Compact 15 lb weight and small footprint
- Clear LCD display for easy monitoring
- CSA certified for outdoor safety
Cons
- Lower flow rate than fixed outdoor units
- Requires 2 D-cell batteries for ignition
- No built-in water pump in standard version
Good fit if
- You need a lightweight heater for camping
- You want instant hot water in an RV
- You prefer manual temperature control
Skip if
- You require high flow for multiple fixtures
- You need a permanent outdoor installation
- You want electric ignition without batteries
Verdict: Camplux F10 2.64 GPM Propane Heater is a compact, CSA-certified choice for campers and RVers who prioritize portability and instant hot water over high flow rates.
GASLAND 1.58 GPM Portable Propane Water Heater
Best for: camping and low-pressure outdoor setups
- Installation Location
- Outdoor (what this guide is about)
- Fuel Type
- Propane
- Flow Rate
- 1.58 GPM
- BTU
- 41,000 BTU/hr
- Certification
- CSA
- Dimensions
- 17.3 x 6.1 x 11.8 in
View on Amazon: GASLAND 1.58 GPM Portable Propane Water Heater
The GASLAND BS158 is a portable outdoor propane water heater with a 41,000 BTU/hr output and a 1.58 GPM flow rate. It starts at just 3.6 PSI and runs on a standard 20 lb tank. This unit suits you if you need hot water for camping, RVs, or outdoor cleaning. Its compact size and low water pressure requirement make it easy to set up anywhere without complex plumbing.
Pros
- 41,000 BTU/hr maximum power output
- 1.58 GPM flow rate for instant hot water
- Starts with low water pressure of 3.6 PSI
- Runs on standard 20 lb propane tank
- CSA certified for safety compliance
Cons
- 1.58 GPM flow rate is lower than many competitors
- Not suitable for altitudes over 3,300 feet
- Vulnerable to damage from prolonged rain exposure
Good fit if
- You need a compact unit for camping or RV trips
- You have low water pressure at your outdoor source
- You want a CSA-certified heater for safe outdoor use
Skip if
- You require a flow rate above 2.0 GPM
- You live or camp above 3,300 feet elevation
- You need a unit that withstands heavy rain exposure
Verdict: The GASLAND BS158 1.58 GPM Propane Heater is a practical pick for campers and RVers who prioritize portability and low water pressure startup over high flow rates. It fits users who need a certified, off-grid solution for temporary outdoor hot water needs.
Specifications side by side
| Spec | Camplux 5L Portable Propane Water Heater | Camplux 2.11 GPM Portable Outdoor Propane Water Heater | Ranein 8.5 GPM Outdoor Propane Water Heater | VEVOR 5.3 Gal Outdoor Propane Tankless Heater | Camplux 6L Portable Propane Water Heater | Ranein 6L Portable Propane Water Heater | APUS 190,000 BTU Outdoor Natural Gas Water Heater | Ranein 18L Outdoor Propane Tankless Water Heater | Rinnai 6.1 GPM Outdoor Propane Water Heater | Camplux 1.32 GPM Portable Propane Heater | Westinghouse 8.1 GPM Propane Outdoor Heater | NOVIEEX 5.3 GPM Outdoor Propane Tankless Water Heater | GASLAND 2.64 GPM Portable Outdoor Propane Water Heater | Camplux 2.64 GPM Portable Propane Water Heater | GASLAND 1.58 GPM Portable Propane Water Heater |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Fuel Type | Propane | Propane | Propane | Propane | Propane | not specified | Natural Gas | Propane | Propane | Propane | Propane | Propane | Propane | Propane | Propane |
| Flow Rate | 1.32 GPM | 2.11 GPM | 8.5 GPM | not specified | 1.58 GPM | not specified | 8.1 GPM | 4.74 GPM | 6.1 GPM | 1.32 GPM | 8.1 GPM | 5.3 GPM | 2.64 GPM | 2.64 GPM | 1.58 GPM |
| BTU | not specified | 55,000 BTU/hr | 190,000 BTU | 120,000 BTU/h | 41,000 BTU/hr | not specified | 190,000 BTU | 85,300 BTU | not specified | not specified | 180,000 BTU | 120,000 BTU | 68,000 BTU/hr | not specified | 41,000 BTU/hr |
| Installation Location | Outdoor | Outdoor | Outdoor | Outdoor | Outdoor | not specified | Outdoor | Outdoor | Outdoor | Outdoor | Outdoor | Outdoor | Outdoor | Outdoor | Outdoor |
| Voltage | not specified | not specified | not specified | not specified | not specified | not specified | 120V AC | not specified | not specified | not specified | 120V AC | 110V-120V AC/60Hz | not specified | not specified | not specified |
| Temperature Control | not specified | 18-95 °F | not specified | ±1°F | 50°F to 122°F | not specified | 95°F–149°F, ±1°F | 55.4°F to 109.4°F | not specified | not specified | ±1°F | 95°F–149°F, ±1°F | not specified | not specified | not specified |
| Certification | CSA | CSA | not specified | not specified | not specified | not specified | not specified | not specified | not specified | CSA | CSA | not specified | CSA | CSA | CSA |
| Dimensions | 4.33 x 11.4 x 14.8 inches | 20.5 x 12.6 x 12.6 inches | 24.3 x 15.1 x 8.1 in | 23.2 x 15 x 15 inches | 17.3 x 5.12 x 11.8 inches | not specified | 22.48 x 15.51 x 6.54 in | 24 x 7.1 x 13.8 inches | 24.6 x 14.1 x 10.8 in | 14.8 x 4.33 x 11.4 inches | 26.8 x 17.1 x 17.1 inches | 23.7 x 15 x 5.1 inches | 13 x 5.9 x 18.5 inches | 12.9 x 5.9 x 18.5 in | 17.3 x 6.1 x 11.8 in |
| Use | Camping, RV | Camping | not specified | Whole House | Camping, RV, Cabins | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | Camping, RV | not specified |
| Venting Type | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | Non-Condensing | not specified | not specified | not specified | not specified | not specified | not specified |
| Features | Overheat Protection | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified |
| Weight | 10 pounds | 19 pounds | 44 pounds | 29.1 pounds | 14 pounds | 9.92 pounds | 42.5 pounds | not specified | 49.2 pounds | 10 pounds | 42 pounds | 34 pounds | 17.2 pounds | 15 pounds | not specified |
| Size | Classic | not specified | 8.5 GPM Outdoor | 5.3 Gal | not specified | not specified | not specified | not specified | 6.6 GPM | 1.32 GPM | not specified | not specified | not specified | not specified | not specified |
| Color | White | White | Gray-LPG | Silver Gray | White | Gray | Gray | Gray | Silver | Black | Grey 81LPO | Gray | White | White | White |
| Model | AY132 | BW211 | RHO19K-LPG | JSW38-20L-B | BD158N | RO4K-Y | AP-AWH-W26NG | TMYD-01020120 | REU-VE2125WD-US-P | AY132BN | HS180A0G-LP | HS-20 | G10N | F10CA | BS158 |
Is an Outdoor Installation Worth It?
Outdoor placement removes the need for indoor venting, which simplifies installation for natural gas and propane units. You gain flexibility by mounting the unit on exterior walls, keeping noisy components away from living spaces. Portable models offer mobility for camping or RV use, while fixed whole-house units provide dedicated exterior heating. However, outdoor units require protection from weather and may need anti-freeze features in cold climates. You must also ensure access to propane tanks or natural gas lines outside.
Worth it if
- You want to avoid complex indoor venting requirements for gas units
- You need a portable heating solution for camping or RV use
- You have an existing natural gas line or propane access outside
Skip it if
- You live in a climate with freezing temperatures without anti-freeze protection
- You lack outdoor access to propane tanks or natural gas lines
- You need to hide the unit from view on your exterior walls
If you need fixtures to match, see our guide on the best outdoor showers for outdoor.
How We Picked These Models
We selected these 15 tankless water heaters by filtering Amazon listings for the Installation Location: Outdoor feature. This ensures every model is designed for exterior mounting. We verified this detail directly from the product titles and feature lists on each listing. Only one size or variant from each product family appears here.
We ordered the list by availability first. Next, we sorted by overall rating weighted by review count. Finally, we considered how well each spec met our criteria. All data comes from published specifications. We do not test products or handle them physically. Prices and stock status update live on the page.
How to Choose the Right Outdoor Tankless Heater
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Match Flow Rate to Fixtures
Check the gallons per minute (GPM) rating to ensure the unit handles your simultaneous needs. The Rheem RTG offers 9.5 GPM, supporting multiple showers in large homes. For single outdoor taps, smaller units like the Camplux 5L provide 1.32 GPM. Higher GPM models require larger gas lines and professional installation. Lower GPM units suit portable camping showers. Verify the spec matches your fixture count to avoid temperature drops during use.
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Select Fuel Type Carefully
Choose between propane, natural gas, or dual-fuel based on your available supply. Propane units like the VEVOR 5.3 Gal work off-grid without fixed lines. Natural gas models like the APUS require a permanent exterior connection. Propane offers mobility for camping, while natural gas provides continuous supply for whole-house use. Ensure your fuel source matches the heater’s inlet requirements. Mismatched fuel types prevent ignition or cause damage. Check the product attributes for the specific fuel type supported.
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Verify Voltage and Power Needs
Determine if the unit requires standard electrical power or runs on batteries. The APUS 190,000 BTU model needs 120V power for its digital controls and blower. Portable Camplux units use battery ignition, allowing operation without grid power. Battery models suit remote campsites. Electric-dependent units need nearby outlets or generator access. Check the specs for power requirements. This decision affects where you can mount the heater and how you supply energy to it.
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Check Elevation and BTU Output
High elevations reduce combustion efficiency, requiring higher BTU ratings to maintain temperature. The NOVIEEX 5.3 GPM model delivers 120,000 BTU, suitable for setups under 2,000 feet. The Ranein 5.3 GPM unit provides 130,000 BTU for similar low-elevation outdoor use. Higher BTU units compensate for thin air. If you live above 2,000 feet, verify if the model is rated for your altitude. Lower BTU units may struggle to heat water adequately in high-altitude environments.
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Consider Portability and Weight
Evaluate the unit’s weight and dimensions if you plan to move it frequently. The Camplux 5L weighs only 10 pounds, making it ideal for backpacking or RV storage. The Rinnai 6.1 GPM unit weighs 49.2 pounds, designed for permanent outdoor mounting. Heavier units offer higher flow rates but lack mobility. Lighter units suit single-tap outdoor showers. Check the weight spec in the product data. Your choice depends on whether you need a fixed installation or a portable solution.
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Review Venting Requirements
Outdoor installation simplifies venting, but non-condensing units still require proper exhaust clearance. The Rinnai RE160eP is a non-condensing unit designed for exterior walls. Non-condensing models vent hot exhaust directly outside. Ensure you have adequate clearance around the unit. Some portable units have no venting concerns due to their open design. Check the venting type in the attributes. Proper venting prevents carbon monoxide buildup and ensures safe operation in enclosed outdoor spaces like patios.
Frequently asked questions
Can I use a tankless water heater outdoors in freezing weather?
Yes, but you must select a model with built-in freeze protection. The Westinghouse 8.1 GPM Propane Outdoor Heater includes this feature to prevent internal damage. Without it, standing water in the heat exchanger can expand and crack the unit. You should also drain the system if you leave it unused for long periods in cold climates.
What is the difference between condensing and non-condensing outdoor units?
Non-condensing units vent hot exhaust gases directly outside, while condensing models capture latent heat for higher efficiency. The Rinnai RE160eP is a dedicated outdoor non-condensing model. Non-condensing units are often simpler to install outdoors because they do not require special sealed venting. Condensing units typically require more complex drainage for acidic condensate.
How do I choose the right flow rate for my outdoor needs?
Match the gallons per minute (GPM) rating to your simultaneous water usage. Single outdoor showers or washing tasks need 1.32 to 2.64 GPM. Whole-house heating requires 5.3 to 8.5 GPM. The Ranein 8.5 GPM model supports large households, while the Camplux 5L at 1.32 GPM is sufficient for basic camping hygiene.
Do I need a remote control for an outdoor tankless heater?
A remote control is useful for adjusting settings without going outside. The VEVOR 5.3 Gal unit includes a 32.8-foot wired remote for indoor management. This allows you to change temperature settings from a comfortable location. Many portable camping models lack remotes, requiring manual adjustment at the unit itself.
What fuel types are available for outdoor installation?
Propane and natural gas are the primary fuel options for outdoor tankless heaters. Propane units like the Camplux and Ranein models offer portability and independence from fixed gas lines. Natural gas units like the APUS 190,000 BTU model connect to existing home gas lines. Propane is ideal for off-grid locations, while natural gas provides continuous supply for permanent homes.
How heavy are portable outdoor water heaters?
Portable models typically weigh between 10 and 19 pounds for easy transport. The Ranein 6L weighs 9.92 pounds, making it the lightest option. The Camplux 5L weighs 10 pounds. Fixed whole-house units are much heavier, often exceeding 40 pounds. You should check the weight specification to ensure you can safely move and mount the unit.
Can I use these heaters at high elevations?
Some models have specific elevation limits that affect performance. The Ranein 8.5 GPM unit is rated for use below 2,000 feet. The NOVIEEX 5.3 GPM model also specifies performance under 2,000 feet elevation. At higher altitudes, air density changes can reduce heating efficiency. You must verify the elevation rating before purchasing for mountain locations.