6 Best Alternatives to the Rinnai RUS75eP Tankless Hot Water (2026)
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The Rinnai RUS75eP delivers 7.5 GPM of hot water for large outdoor propane setups. If you need rinnai rus75ep tankless hot water alternatives, you might want a different flow rate, indoor placement, or a different brand. This unit requires outdoor installation and uses propane. Some buyers prefer indoor models or natural gas fuel. Others need higher flow or smaller dimensions. The alternatives listed here share key specs with the original. They match the fuel type or flow capacity. Each option offers a distinct advantage. You can choose based on your specific needs. The list covers top picks for various scenarios. Some models prioritize compact size. Others focus on precise temperature control. All options provide reliable performance. You can find the right fit for your home. The selection is based on published specifications. We compared flow rates and dimensions. This ensures you get accurate information. Your choice depends on your unique requirements. Read on to see the best matches.
Our top pick: Rinnai 7.5 GPM Outdoor Propane Tankless Water Heater.
How each alternative compares
Rinnai 6.1 GPM Outdoor Propane Water Heater
The Rinnai RE160eP offers a slightly lower 6.6 GPM flow rate compared to the 7.5 GPM in the RUS75eP. It is more compact, measuring 24.6 inches tall and weighing 49.2 pounds. This model uses non-condensing venting, which simplifies installation for outdoor propane setups. You get a smaller footprint if space is tight, but you sacrifice some simultaneous fixture capacity. This unit suits buyers who prioritize a streamlined design over maximum water volume. It remains a solid outdoor choice for homes with moderate hot water demands.
Westinghouse 8.1 GPM Propane Outdoor Heater
The Westinghouse HS180A0G-LP provides a higher 8.1 GPM flow rate, exceeding the RUS75eP performance. It is designed for outdoor propane use and weighs only 42 pounds. The unit measures 26.8 inches in height. This model delivers robust output for high-demand households requiring precise temperature stability across multiple fixtures. You gain increased flow speed and a lighter chassis. However, the brand offers less established residential warranty support than Rinnai. This heater is ideal for outdoor whole-home applications where peak performance matters more than brand heritage.
Rheem RTG 7.0 GPM Propane Outdoor
The Rheem RTG-70XLP-3 delivers 7.0 GPM, which is slightly less than the RUS75eP. It includes WiFi connectivity for remote monitoring and control, a feature absent in the Rinnai. The unit is compact at 20.8 inches tall and weighs 39.3 pounds. It uses non-condensing venting for outdoor propane installation. You gain smart home integration and precise temperature management. You give up a small amount of flow rate. This model fits outdoor propane homes that value tech features and efficient space usage over maximum simultaneous water delivery.
A. O. Smith 6.6 GPM Outdoor Propane Tankless Water Heater
The A.O. Smith ATO-140H 101 provides 6.6 GPM, offering lower flow than the RUS75eP. It is built for outdoor propane installation and features a white finish. The unit measures 22.9 inches tall and weighs 52 pounds. This model emphasizes heat transfer efficiency and corrosion resistance. You gain durability and efficient heating performance. You sacrifice higher flow volume. This heater suits outdoor propane users who prioritize long-term component reliability and efficient heat exchange over maximum water output speed.
Marey GA24CSALP 7.5 GPM Propane Heater
The Marey GA24CSALP matches the RUS75eP with 7.5 GPM flow but is designed for indoor installation. It uses propane and weighs 40.8 pounds. The unit is significantly narrower at 7.3 inches deep. This model fits homes needing strong indoor performance without sacrificing flow rate. You gain flexibility in placement and a compact vertical design. You lose outdoor durability and weather resistance. This heater is ideal for families requiring high simultaneous fixture support in indoor utility spaces where space is limited.
Camplux 5L Portable Propane Water Heater
The Camplux AY132 is a portable 5L propane heater designed for camping and RV use. It weighs only 10 pounds and measures 4.33 inches tall. This unit provides on-demand hot water for off-grid adventures. It features overheat protection for safety. You gain extreme portability and battery operation. You sacrifice whole-home capacity and fixed installation benefits. This heater is strictly for temporary or recreational use. It does not replace a residential tankless system but serves campers needing reliable hot water in remote locations.
Quick picks
Our 7 picks
Rinnai 7.5 GPM Outdoor Propane Tankless Water Heater
Best for: large households needing high simultaneous flow
- Fuel Type
- Propane
- Flow Rate
- 7.5 GPM
- Installation Location
- Outdoor
- Dimensions
- 35 x 14.5 x 22 inches
- Weight
- 63 pounds
View on Amazon: Rinnai 7.5 GPM Outdoor Propane Tankless Water Heater
The Rinnai RUS75eP delivers up to 7.5 gallons per minute of hot water using propane. This outdoor unit measures 35 by 14.5 by 22 inches and weighs 63 pounds. It serves up to six appliances simultaneously. The compact design saves space while offering flexible venting options. You should choose this model if you need high flow rates for multiple bathrooms or large households requiring reliable, endless hot water.
Pros
- Provides up to 7.5 GPM flow rate
- Serves up to six appliances at once
- Compact outdoor dimensions of 35 x 14.5 x 22 inches
- Flexible venting with PVC or CPVC options
Cons
- Heavier build at 63 pounds
- Professional installation is required
- Limited to outdoor placement only
Good fit if
- You need high flow for multiple bathrooms
- You have an outdoor installation space
- You use propane as your fuel source
Skip if
- You require indoor installation
- You prefer natural gas over propane
- You want a DIY-friendly setup
Verdict: Rinnai RUS75eP 7.5 GPM Propane Outdoor Heater is the right fit for large homes needing simultaneous hot water access. It suits buyers with outdoor space and propane lines who prioritize consistent flow over compact indoor placement.
Rinnai 6.1 GPM Outdoor Propane Water Heater
Best for: compact outdoor propane hot water needs
- Fuel Type
- Propane
- Flow Rate
- 6.1 GPM
- BTU
- 160k BTU
- Installation Location
- Outdoor
- Dimensions
- 24.6 x 14.1 x 10.8 in
- Venting Type
- Non-Condensing
The Rinnai RE160eP is a non-condensing propane water heater designed for outdoor installation. It delivers a flow rate of 6.6 GPM, supporting up to five simultaneous fixtures. The unit measures 24.6 by 14.1 by 10.8 inches and weighs 49.2 pounds. Its compact footprint allows for flexible placement. You get an LED screen for error codes and service reminders. This model suits homes needing reliable outdoor hot water without the complexity of condensing systems.
Pros
- 6.6 GPM flow rate for multiple fixtures
- Compact outdoor design fits small spaces
- LED screen displays error codes and reminders
- Non-condensing venting simplifies installation
Cons
- Flow rate is lower than some competitors
- WiFi control requires a separate module
- Labor warranty drops to one year if unregistered
Good fit if
- You need a durable outdoor propane heater
- You want a compact unit for tight spaces
- You prefer non-condensing venting simplicity
Skip if
- You require built-in WiFi connectivity
- You need a flow rate above 8 GPM
- You plan to install the unit indoors
Verdict: Rinnai RE160eP 6.6 GPM Propane Outdoor Heater delivers steady hot water for outdoor use. It fits buyers who value compact size and straightforward non-condensing venting over maximum flow speed.
Westinghouse 8.1 GPM Propane Outdoor Heater
Best for: outdoor whole-home hot water needs
- Fuel Type
- Propane
- Flow Rate
- 8.1 GPM
- BTU
- 180,000 BTU
- Installation Location
- Outdoor
- Voltage
- 120 V AC
- Temperature Control
- ±1°F
This outdoor propane tankless water heater delivers 8.1 GPM and 180,000 BTU. It supports 3–5 fixtures simultaneously with ±1°F temperature stability. The unit includes a wired digital controller for precise adjustments between 95°F and 158°F. It features integrated freeze protection and a variable-speed combustion fan for year-round outdoor use. This model suits homes needing high flow rates in outdoor settings.
Pros
- 8.1 GPM flow rate supports multiple fixtures
- 180,000 BTU output for whole-home hot water
- ±1°F temperature stability prevents fluctuations
- Wired digital controller for remote adjustment
- Integrated freeze protection for outdoor reliability
Cons
- 2-year limited warranty is shorter than the 5-year heat exchanger coverage
- Requires 120V AC power for operation
- Lacks wireless app or smart home connectivity
Good fit if
- You need high flow for 3–5 simultaneous fixtures
- You require precise temperature control without fluctuations
- You are installing the unit in an outdoor location
Skip if
- You need a unit for indoor installation only
- You prefer a longer standard warranty on the entire unit
- You want wireless app control for temperature management
Verdict: Westinghouse 8.1 GPM Propane Outdoor Heater provides robust performance for high-demand households. It is ideal for outdoor installations where precise temperature stability and multi-fixture support are priorities.
Rheem RTG 7.0 GPM Propane Outdoor
Best for: outdoor propane homes needing precise temp control
- Fuel Type
- Liquid Propane
- Flow Rate
- 7.0 GPM
- BTU
- 160,000 BTU/hr
- Installation Location
- Outdoor
- Temperature Control
- ±1°F
- Certification
- CSA
The Rheem RTG-70XLP-3 delivers 7.0 GPM of hot water at 160,000 BTU/hr. It uses liquid propane and features a non-condensing design for outdoor use. You get digital LED control with ±1°F precision and built-in freeze protection. The unit weighs 39.3 pounds and measures 20.8 x 13.5 x 9.4 inches. It suits homes needing reliable whole-house heating with precise temperature management.
Pros
- 7.0 GPM flow rate supports 2-3 simultaneous showers
- 160,000 BTU/hr output for high demand
- Digital LED panel allows ±1°F temperature adjustments
- Built-in freeze and flame failure protection
- 15-year heat exchanger warranty included
Cons
- Non-condensing design has lower efficiency than condensing models
- Requires professional installation
- No WiFi connectivity in this 7.0 GPM variant
Good fit if
- You need a high-flow outdoor propane heater
- You want precise digital temperature control
- You prefer a non-condensing outdoor unit
Skip if
- You require indoor installation
- You need WiFi smart home integration
- You are looking for a condensing high-efficiency model
Verdict: Rheem RTG 7.0 GPM Propane is a solid choice for outdoor propane setups needing precise temperature control and high flow. It fits homes with multiple bathrooms but lacks smart features for tech-focused users.
A. O. Smith 6.6 GPM Outdoor Propane Tankless Water Heater
Best for: Outdoor propane users prioritizing heat transfer efficiency
- Fuel Type
- Propane
- Flow Rate
- Up to 6.6 GPM
- BTU
- 120,000 BTU
- Installation Location
- Outdoor
- Venting Type
- Condensing
- Dimensions
- 13.9 × 13.9 × 22.9 inches
View on Amazon: A. O. Smith 6.6 GPM Outdoor Propane Tankless Water Heater
The A.O. Smith ATO-140H delivers 6.6 GPM of hot water using 120,000 BTU of propane. Its outdoor wall-mount design fits tight spaces, measuring 22.9 x 13.9 x 13.9 inches. The unit uses a copper heat exchanger for faster temperature stabilization and includes a secondary stainless steel exchanger for corrosion resistance. This model suits households needing reliable outdoor propane heating with efficient heat transfer.
Pros
- 6.6 GPM continuous flow rate for multiple fixtures
- Primary copper heat exchanger transfers heat 25x better than stainless steel
- Secondary 316L stainless steel exchanger resists corrosion
- Flexible venting with 3-inch PVC up to 70 feet
Cons
- Lower flow rate than the Westinghouse 8.1 GPM alternative
- Heavier at 52 pounds compared to lighter portable options
- Outdoor installation only, limiting indoor placement flexibility
Good fit if
- You need a durable outdoor unit with copper heat exchange
- You have limited wall space for a compact 13.9-inch width
- You want flexible venting options up to 100 feet
Skip if
- You require an indoor installation model
- You need a flow rate higher than 6.6 GPM
- You prefer a lighter unit under 50 pounds
Verdict: A.O. Smith 6.6 GPM Propane Outdoor Heater is a solid choice for outdoor propane setups where heat transfer speed and corrosion resistance matter more than maximum flow volume.
Marey GA24CSALP 7.5 GPM Propane Heater
Best for: Indoor high-flow propane needs
- Fuel Type
- Liquid Propane
- Flow Rate
- 7.5 GPM
- BTU
- 170,000 BTU
- Installation Location
- Indoor
- Certification
- CSA
- Dimensions
- 26.2 x 17.1 x 7.3 inches
The Marey GA24CSALP is a propane tankless water heater designed for indoor installation. It delivers 7.5 GPM with 170,000 BTU of heating power. The compact unit measures 26.2 x 17.1 x 7.3 inches and weighs 40.8 pounds. CSA certification ensures safety standards. It supports 3-4 simultaneous use points. This model suits homes needing high flow rates in a space-saving footprint.
Pros
- 7.5 GPM flow rate for multiple fixtures
- 170,000 BTU heating capacity
- CSA certified for safety
- Indoor installation capability
- Compact 7.3-inch depth
Cons
- Not recommended for elevations above 2,000 ft
- Limited to 5-year warranty
- Requires professional installation
Good fit if
- You need indoor propane heating
- You require high flow rates
- You have limited wall space
Skip if
- You live above 2,000 ft elevation
- You prefer outdoor installation
- You want a longer warranty
Verdict: Marey 7.5 GPM Propane Indoor Heater fits homes needing strong indoor performance. It works well for families running multiple fixtures at once. The compact design saves space without sacrificing flow rate.
Camplux 5L Portable Propane Water Heater
Best for: camping and off-grid showers
- Fuel Type
- Propane
- Flow Rate
- 1.32 GPM
- Installation Location
- Outdoor
- Certification
- CSA
- Dimensions
- 4.33 x 11.4 x 14.8 inches
- Use
- Camping, RV
This portable tankless water heater uses propane to deliver 1.32 GPM of hot water. It weighs just 10 lbs and measures 4.33 by 11.4 by 14.8 inches, making it easy to carry in your car or RV. It starts with low water pressure and needs no electricity. The unit is CSA certified for outdoor safety. You get instant heat for camping or off-grid living without waiting for a tank to refill.
Pros
- Delivers 1.32 GPM flow rate
- Weighs only 10 lbs for portability
- Starts at 3.0 PSI water pressure
- CSA certified for safety
Cons
- Low 1.32 GPM flow rate limits simultaneous use
- Requires two D-size batteries for ignition
- Outdoor installation only
Good fit if
- You need a lightweight heater for camping trips
- You want a unit that works with low water pressure
- You require a CSA certified outdoor heater
Skip if
- You need high flow rates for multiple showers
- You want an indoor installation option
- You prefer a unit with built-in electrical power
Verdict: Camplux 5L Portable Propane Heater is a compact, battery-powered solution for campers who need reliable hot water on the go. It fits perfectly in your gear bag for off-grid adventures.
Specifications side by side
| Spec | Rinnai 7.5 GPM Outdoor Propane Tankless Water Heater | Rinnai 6.1 GPM Outdoor Propane Water Heater | Westinghouse 8.1 GPM Propane Outdoor Heater | Rheem RTG 7.0 GPM Propane Outdoor | A. O. Smith 6.6 GPM Outdoor Propane Tankless Water Heater | Marey GA24CSALP 7.5 GPM Propane Heater | Camplux 5L Portable Propane Water Heater |
|---|---|---|---|---|---|---|---|
| Fuel Type | Propane | Propane | Propane | Liquid Propane | Propane | Liquid Propane | Propane |
| Flow Rate | 7.5 GPM | 6.1 GPM | 8.1 GPM | 7.0 GPM | Up to 6.6 GPM | 7.5 GPM | 1.32 GPM |
| BTU | not specified | 160k BTU | 180,000 BTU | 160,000 BTU/hr | 120,000 BTU | 170,000 BTU | not specified |
| Installation Location | Outdoor | Outdoor | Outdoor | Outdoor | Outdoor | Indoor | Outdoor |
| Voltage | not specified | not specified | 120 V AC | not specified | not specified | not specified | not specified |
| Temperature Control | not specified | not specified | ±1°F | ±1°F | not specified | not specified | not specified |
| Certification | not specified | not specified | CSA | CSA | not specified | CSA | CSA |
| Dimensions | 35 x 14.5 x 22 inches | 24.6 x 14.1 x 10.8 in | 26.8 x 17.1 x 17.1 in | 20.8 x 13.5 x 9.4 inches | not specified | 26.2 x 17.1 x 7.3 inches | 4.33 x 11.4 x 14.8 inches |
| Use | not specified | not specified | Whole House | not specified | not specified | not specified | Camping, RV |
| Venting Type | not specified | Non-Condensing | not specified | Non-Condensing | Condensing | not specified | not specified |
| Features | not specified | not specified | not specified | WiFi | not specified | not specified | Overheat Protection |
| Weight | 63 pounds | 49.2 pounds | 42 pounds | 39.3 pounds | 52 pounds | 40.8 pounds | 10 pounds |
| Size | 7.5 GPM | 6.6 GPM | not specified | 7.0 GPM (Non-WiFi) | not specified | 24L | Classic |
| Color | Outdoor Installation | Silver | Grey 81LPO | Gray | White | White | White |
| Model | RUS Series | REU-VE2125WD-US-P | HS180A0G-LP | RTG-70XLP-3 | ATO-140H 101 | GA24CSALP | AY132 |
For drinking water filtration specifications, you can evaluate apec water tankless reverse osmosis water alternatives.
Frequently asked questions
Which tankless water heater offers the highest flow rate for large households?
The Westinghouse 8.1 GPM Propane Outdoor Heater provides the highest flow rate on this list. It delivers 8.1 gallons per minute, making it suitable for whole-home hot water needs. This unit measures 26.8 inches in height and weighs 42 pounds. It is designed for outdoor installation and supports simultaneous multi-fixture use.
What is the best indoor propane tankless water heater option?
The Marey GA24CSALP 7.5 GPM Propane Heater is the top choice for indoor installation. It matches the 7.5 GPM output of the Rinnai RUS75eP while fitting in tighter spaces. Its compact design measures only 7.3 inches in length. This model is ideal for families needing strong indoor performance without sacrificing flow rate.
How does the Rheem RTG 7.0 GPM compare in size to the Rinnai RUS75eP?
The Rheem RTG 7.0 GPM is significantly more compact than the Rinnai RUS75eP. It measures 20.8 inches tall and 9.4 inches long, weighing just 39.3 pounds. The Rinnai RUS75eP is taller at 35 inches and heavier at 63 pounds. The Rheem model offers precise temperature control for outdoor propane setups.
Is there a portable propane heater suitable for camping?
Yes, the Camplux 5L Portable Propane Water Heater is designed for camping and off-grid use. It is battery-powered and weighs only 10 pounds. Its compact dimensions allow it to fit easily into a gear bag. This unit includes overheat protection for safe operation during outdoor adventures.
Which model features WiFi connectivity for remote control?
The Rheem RTG 7.0 GPM Propane Outdoor Heater includes WiFi features. This allows you to monitor and adjust settings remotely. Most other models on this list, such as the Rinnai RE160eP and Westinghouse HS180A0G-LP, do not list smart connectivity. The Rheem unit is a solid choice for tech-focused users.
What are the dimensions of the A.O. Smith 6.6 GPM heater?
The A.O. Smith ATO-140H 101 measures 22.9 inches in height, 13.9 inches in width, and 13.9 inches in length. It weighs 52 pounds. This model prioritizes heat transfer efficiency and corrosion resistance. It is designed for outdoor propane installations where these specific performance traits are valued over maximum flow volume.
Which alternative is the most compact for outdoor installation?
The Rinnai RE160eP 6.6 GPM Outdoor Propane Heater is the most compact option for outdoor use. It measures 24.6 inches tall, 14.1 inches wide, and 10.8 inches long. Weighing 49.2 pounds, it fits buyers who value a smaller footprint. It uses non-condensing venting, which simplifies installation compared to condensing models.