Looking Beyond the Furrion 2021123985 Tankless Gas Water? 6 Alternatives Worth a Look
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If you are researching furrion 2021123985 tankless gas water alternatives, you likely value its compact retrofit design and consistent temperature control. The Furrion unit delivers 2.4 GPM, which suits RVs or single fixtures well. However, its low flow rate limits whole-house use. You might need higher capacity or a different fuel type for your specific needs. Some buyers prefer electric options or higher output for larger families. Others want outdoor durability or smart connectivity features not present in this model.
We selected these alternatives because their specifications overlap with the original product’s core requirements. The list includes electric heaters for homes with strong electrical capacity and high-output gas units for whole-house demand. You will find options with higher flow rates, such as 6.1 GPM and 8.4 GPM models, as well as propane and natural gas variants. Each choice addresses specific gaps, whether you need indoor venting, outdoor placement, or smart monitoring. Review the specs to find the unit that matches your home’s infrastructure and hot water demands.
Our top pick: Furrion 2.4 GPM Gas Tankless Water Heater.
How alternatives differ from Furrion
Stiebel Eltron Tempra 29 Plus 28.8kW Tankless
The Stiebel Eltron Tempra 29 Plus switches from gas to electric power. It requires a 240V circuit and delivers 8 kW of heating capacity. This unit measures 16.6 inches wide and weighs 19 pounds. It suits homes with strong electrical capacity but no gas lines. You give up gas flexibility for electric precision. It fits users who need high output without venting concerns. The compact white design saves space. Choose this if your electrical panel can handle the load and you prefer electric reliability over gas maintenance.
Rinnai 6.1 GPM Outdoor Propane Water Heater
The Rinnai RE160eP offers 6.6 GPM on propane, far exceeding the Furrion’s 2.4 GPM. It is designed for outdoor installation with non-condensing venting. The unit measures 14.1 inches wide and 24.6 inches tall, weighing 49.2 pounds. It features an LED display for maintenance alerts. You gain high flow for multiple fixtures outdoors. You lose indoor versatility and gas line convenience. This model suits homeowners with limited outdoor space who prioritize durability. Pick this if you need robust propane performance for outdoor showers or kitchens.
Rheem RTG 8.4 GPM Indoor Natural Gas Water Heater
The Rheem RTG-84DVLN provides 8.4 GPM on natural gas for indoor use. It uses non-condensing venting and measures 13.5 inches wide. The unit weighs 46.5 pounds. It handles whole-house demand for large families with simultaneous water needs. You gain massive flow compared to the Furrion’s single-fixture limit. You need indoor direct venting capability. This model fits homes with high water demand. Choose this if you require consistent hot water for multiple bathrooms and have the venting infrastructure for a larger indoor natural gas unit.
Westinghouse 7.9 GPM Natural Gas Tankless Water Heater
The Westinghouse APOLO-180K delivers 7.9 GPM on natural gas for indoor whole-home use. It measures 17.1 inches wide and 26.2 inches tall, weighing 39.3 pounds. It offers precise temperature control and smart connectivity. You gain remote management and steady hot water for large households. You sacrifice outdoor versatility for indoor convenience. This model suits households prioritizing smart features. Pick this if you need reliable indoor whole-home heating with modern connectivity options and do not require outdoor installation flexibility.
Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater
The Rheem RTG-84XLN provides 8.4 GPM on natural gas for outdoor installation. It features WiFi connectivity and non-condensing venting. The unit measures 13.5 inches wide and weighs 39.3 pounds. It handles whole-house demand for large families with multiple bathrooms. You gain high capacity and smart monitoring outdoors. You lose indoor placement options. This model fits homes with outdoor mounting space. Choose this if you need robust outdoor performance with remote monitoring capabilities and require high flow for whole-house usage.
Rheem RTG 8.4 GPM Outdoor Propane Tankless Water Heater
The Rheem RTG-84XLP offers 8.4 GPM on propane for outdoor use. It includes WiFi connectivity and non-condensing venting. The unit measures 13.5 inches wide and weighs 39.3 pounds. It provides precise temperature control for whole-house demand. You gain high capacity and smart features on propane. You sacrifice indoor versatility. This model suits buyers prioritizing high output over indoor placement. Pick this if you need robust outdoor propane performance with remote management and require consistent hot water for large households.
Quick picks
Our 7 picks
Furrion 2.4 GPM Gas Tankless Water Heater
Best for: RVs and single fixture gas needs
- Fuel Type
- Gas
- Flow Rate
- 2.4 GPM
View on Amazon: Furrion 2.4 GPM Gas Tankless Water Heater Affiliate link
The Furrion 2021123985 is a white, standard-size gas tankless water heater with a 2.4 GPM flow rate. It features electronic ignition, a low pressure alarm, and a retrofit design. This unit delivers consistent temperature control for single-point applications. It suits you if you need a compact gas solution for an RV or small bathroom where space is limited and a 2.4 GPM output is sufficient.
Pros
- 2.4 GPM flow rate for steady hot water
- Electronic ignition for reliable startup
- Low pressure alarm for system protection
- Retrofit design for easy installation
Cons
- 2.4 GPM flow rate limits simultaneous use
- Gas fuel type requires venting infrastructure
- No built-in mixing valve mentioned in specs
Good fit if
- You need a compact unit for an RV
- You require a retrofit-friendly gas heater
- You only need hot water for one fixture
Skip if
- You need high flow for multiple showers
- You prefer electric power sources
- You require outdoor-rated durability
Verdict: Furrion 2.4 GPM Gas Tankless Heater fits you if you need a compact, gas-powered solution for an RV or single bathroom. Its low flow rate makes it unsuitable for whole-house use.
Stiebel Eltron Tempra 29 Plus 28.8kW Tankless
Best for: homes with strong electrical capacity
- Fuel Type
- Electric
- Wattage
- 28.8 kW
- Voltage
- 208 V, 240 V
- Dimensions
- 14.5 x 16.6 x 4.63 in
- Use
- Whole House
- Weight
- 19 pounds
View on Amazon: Stiebel Eltron Tempra 29 Plus 28.8kW Tankless Affiliate link
This Stiebel Eltron unit delivers 28.8 kW of heating power at 240 volts. It measures 14.5 by 16.6 by 4.63 inches and weighs 19 pounds. The device uses two temperature memory presets for control. You need dedicated 40 amp breakers and 8 gauge copper wiring. It requires a minimum 200 amp residential service. This model suits homes with strong electrical capacity.
Pros
- 28,800 watts at 240 volts
- Compact 14.5 x 16.6 x 4.63 inch design
- Two temperature memory presets
- No venting required
Cons
- Requires three separate 40 amp breakers
- Needs 8 gauge copper wiring
- Minimum 200 amp total service required
Good fit if
- You have a 200 amp electrical service
- You can install dedicated 40 amp breakers
- You want a compact electric unit
Skip if
- You only have a 100 amp service
- You cannot run 8 gauge copper wiring
- You need gas fuel type
Verdict: Stiebel Eltron Tempra 29 Plus Electric works for homes with robust 200 amp electrical systems. It fits users who need high output without gas lines.
Rinnai 6.1 GPM Outdoor Propane Water Heater
Best for: outdoor propane users needing high flow
- 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
View on Amazon: Rinnai 6.1 GPM Outdoor Propane Water Heater Affiliate link
The Rinnai RE160eP is a non-condensing outdoor tankless water heater designed for propane fuel. It delivers a flow rate of 6.6 GPM, allowing you to run up to five fixtures simultaneously. Its compact dimensions of 24.6 x 14.1 x 10.8 inches fit well in tight spaces. The unit features an LED screen for error codes and service reminders. It includes a 15-year heat exchanger warranty, making it a durable option for outdoor residential use.
Pros
- 6.6 GPM flow rate supports multiple simultaneous uses
- Compact outdoor design fits small spaces
- 15-year limited heat exchanger warranty
- LED screen displays error codes and service reminders
Cons
- Propane fuel only, not compatible with natural gas
- Outdoor installation only, not suitable for indoor use
- WiFi control module sold separately
Good fit if
- You need a high-flow outdoor unit for propane
- You want a durable heater with a long heat exchanger warranty
- You have limited outdoor space for installation
Skip if
- You require indoor installation capabilities
- You use natural gas instead of propane
- You want built-in WiFi control without extra purchases
Verdict: Rinnai RE160eP 6.6 GPM Propane is a robust outdoor solution for users needing high flow rates on propane. It suits homeowners with limited outdoor space who prioritize long-term durability and clear maintenance alerts via the LED display.
Rheem RTG 8.4 GPM Indoor Natural Gas Water Heater
Best for: Whole-house indoor natural gas heating
- Fuel Type
- Natural Gas
- Flow Rate
- 8.4 GPM
- BTU
- 180,000 BTU/hr
- Installation Location
- Indoor
- Temperature Control
- ±1°F
- Certification
- CSA
View on Amazon: Rheem RTG 8.4 GPM Indoor Natural Gas Water Heater Affiliate link
The Rheem RTG-84DVLN is an indoor natural gas unit delivering 8.4 GPM at 180,000 BTU. It features a non-condensing design with a 0.82 UEF rating. The unit includes ±1°F digital temperature control and built-in freeze protection. This system supports 3-4 simultaneous showers, making it suitable for whole-house residential use. It requires professional installation and direct venting.
Pros
- 8.4 GPM flow rate for multiple simultaneous uses
- 180,000 BTU/hr output for high performance
- ±1°F precision digital temperature control
- 0.82 Uniform Energy Factor rating
- Built-in freeze protection safety feature
Cons
- Indoor installation only requires direct venting
- Professional installation is mandatory
- Non-condensing design limits efficiency compared to condensing models
Good fit if
- You need high flow for a large family
- You have an indoor space with direct vent capability
- You want precise digital temperature adjustments
Skip if
- You require outdoor installation
- You need a propane fuel type
- You prefer a DIY installation process
Verdict: Rheem RTG-84DVLN 8.4 GPM Natural Gas provides robust whole-house hot water for large families. It fits homes with indoor direct venting needs and high simultaneous water demand.
Westinghouse 7.9 GPM Natural Gas Tankless Water Heater
Best for: indoor whole-home hot water needs
- Fuel Type
- Natural Gas
- Flow Rate
- 7.9 GPM
- BTU
- 180,000 BTU
- Installation Location
- Indoor
- Voltage
- 120 V AC
- Temperature Control
- 95°F–149°F, ±1°F
View on Amazon: Westinghouse 7.9 GPM Natural Gas Tankless Water Heater Affiliate link
This indoor natural gas unit delivers 7.9 GPM with 180,000 BTU. It maintains temperature within ±1°F using self-modulating technology. Built-in WiFi allows app control. It activates at 0.53 GPM and 15 PSI. The 26.2-inch height fits standard spaces. It suits homes needing whole-house hot water with smart features.
Pros
- 7.9 GPM flow rate for multiple showers
- 180,000 BTU heating power
- ±1°F temperature stability
- Built-in WiFi app control
Cons
- Indoor installation only
- 2-year limited warranty on unit
- Requires 120V AC power connection
Good fit if
- You need whole-house hot water capacity
- You want remote app monitoring
- You have low water pressure systems
Skip if
- You require outdoor installation
- You need propane fuel type
- You prefer no electrical connection
Verdict: Westinghouse APOLO-180K 7.9 GPM offers precise temperature control and smart connectivity for indoor whole-home use. It fits households prioritizing steady hot water and remote management over outdoor versatility.
Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater
Best for: large families with outdoor space
- Fuel Type
- Natural Gas
- Flow Rate
- 8.4 GPM
- BTU
- 180,000 BTU/hr
- Installation Location
- Outdoor
- Temperature Control
- ±1°F
- Certification
- CSA
View on Amazon: Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater Affiliate link
This outdoor unit delivers 8.4 GPM at 180,000 BTUs for whole-house hot water. It features a non-condensing design and ±1°F digital temperature control. The gray metal cabinet supports wall mounting. It suits large families needing simultaneous showers. The unit weighs 39.3 pounds and measures 20.8 by 13.5 by 9.4 inches. Professional installation is required for safe operation.
Pros
- 8.4 GPM flow rate for 3-4 simultaneous showers
- 180,000 BTU/hr output for high performance
- Digital LED panel with ±1°F precision control
- Built-in freeze and flame failure protection
Cons
- Outdoor installation only
- No WiFi connectivity in this specific model
- Requires professional installation
Good fit if
- You need high flow for multiple bathrooms
- You have outdoor space for mounting
- You prefer natural gas fuel
Skip if
- You need indoor installation
- You require WiFi remote control
- You use propane fuel
Verdict: Rheem RTG-84XLN 8.4 GPM Natural Gas handles whole-house demand with ease. It fits homes with multiple bathrooms and outdoor mounting space.
Rheem RTG 8.4 GPM Outdoor Propane Tankless Water Heater
Best for: outdoor whole-house propane heating
- Fuel Type
- Liquid Propane
- Flow Rate
- 8.4 GPM at 35°F rise
- BTU
- 180,000 BTU/hr
- Installation Location
- Outdoor
- Temperature Control
- Digital LED, ±1°F
- Certification
- CSA
View on Amazon: Rheem RTG 8.4 GPM Outdoor Propane Tankless Water Heater Affiliate link
This Rheem unit delivers 8.4 GPM at a 35°F rise using 180,000 BTUs of liquid propane. Its outdoor, non-condensing design eliminates complex venting needs. The digital LED panel allows ±1°F precision adjustments. It supports three to four simultaneous showers for whole-house use. The gray metal cabinet is built for wall mounting. This model suits large homes needing high flow without indoor installation constraints.
Pros
- 8.4 GPM flow rate for multiple showers
- 180,000 BTU/hr output capacity
- Digital LED control with ±1°F precision
- Outdoor non-condensing design simplifies installation
- 15-year heat exchanger warranty included
Cons
- Outdoor installation only, not for indoors
- Requires professional installation by a qualified installer
- No WiFi connectivity in this specific 8.4 GPM non-WiFi model
Good fit if
- You need high flow for a large family
- You have an outdoor space for mounting
- You use liquid propane as your fuel source
Skip if
- You require indoor installation
- You need WiFi remote control capabilities
- You are looking for a natural gas unit
Verdict: Rheem RTG-84XLP Outdoor Propane provides robust 8.4 GPM output for outdoor whole-house use. It fits buyers who prioritize high capacity and precise temperature control over smart features or indoor placement.
Specifications side by side
| Spec | Furrion 2.4 GPM Gas Tankless Water Heater | Stiebel Eltron Tempra 29 Plus 28.8kW Tankless | Rinnai 6.1 GPM Outdoor Propane Water Heater | Rheem RTG 8.4 GPM Indoor Natural Gas Water Heater | Westinghouse 7.9 GPM Natural Gas Tankless Water Heater | Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater | Rheem RTG 8.4 GPM Outdoor Propane Tankless Water Heater |
|---|---|---|---|---|---|---|---|
| Fuel Type | Gas | Electric | Propane | Natural Gas | Natural Gas | Natural Gas | Liquid Propane |
| Flow Rate | 2.4 GPM | not stated | 6.1 GPM | 8.4 GPM | 7.9 GPM | 8.4 GPM | 8.4 GPM at 35°F rise |
| BTU | not stated | not stated | 160k BTU | 180,000 BTU/hr | 180,000 BTU | 180,000 BTU/hr | 180,000 BTU/hr |
| Wattage | not stated | 28.8 kW | not stated | not stated | not stated | not stated | not stated |
| Installation Location | not stated | not stated | Outdoor | Indoor | Indoor | Outdoor | Outdoor |
| Voltage | not stated | 208 V, 240 V | not stated | not stated | 120 V AC | not stated | not stated |
| Temperature Control | not stated | not stated | not stated | ±1°F | 95°F–149°F, ±1°F | ±1°F | Digital LED, ±1°F |
| Certification | not stated | not stated | not stated | CSA | CSA | CSA | CSA |
| Dimensions | not stated | 14.5 x 16.6 x 4.63 in | 24.6 x 14.1 x 10.8 in | 24.2 x 13.5 x 10.3 inches | 26.2 x 17.1 x 17.1 in | 20.8 x 13.5 x 9.4 inches | 20.8 x 13.5 x 9.4 inches |
| Use | not stated | Whole House | not stated | not stated | Whole House | not stated | not stated |
| Venting Type | not stated | not stated | Non-Condensing | Non-Condensing | not stated | Non-Condensing | Non-Condensing |
| Features | not stated | not stated | not stated | not stated | WiFi | WiFi | WiFi |
| Weight | not stated | 19 pounds | 49.2 pounds | 46.5 pounds | 39.3 pounds | 39.3 pounds | 39.3 pounds |
| Size | Standard | 29 (kW) | 6.6 GPM | 8.4 GPM (Standard) | APOLO-180K | 8.4 GPM (No WiFi) | 8.4 GPM (Non-WiFi) |
| Color | White | White | Silver | Gray | Grey 79NI | Gray | Gray |
| Model | 2021123985 | 239223 | REU-VE2125WD-US-P | RTG-84DVLN-3 | HW180A0G-NG | RTG-84XLN-3 | RTG-84XLP-3 |
For a related comparison, read apec water apec tankless ro water alternatives.
Frequently asked questions
Which tankless water heater offers the highest flow rate for whole-house use?
The Rheem RTG-84DVLN and RTG-84XLN models both deliver 8.4 GPM. This capacity handles simultaneous demands in large homes with multiple bathrooms. The Rinnai REU-VE2125WD-US-P provides 6.6 GPM, which is lower but still robust for outdoor propane setups. These high-output units suit families needing steady hot water throughout the house.
Can I install a tankless water heater outdoors?
Yes, several models are designed for outdoor placement. The Rinnai REU-VE2125WD-US-P is built for outdoor propane use. The Rheem RTG-84XLN and RTG-84XLP-3 are also outdoor-ready natural gas and propane units. These heaters feature durable construction to withstand external weather conditions while providing consistent heating performance.
Which electric tankless heater is suitable for homes with strong electrical systems?
The Stiebel Eltron Tempra 29 Plus is ideal for homes with robust 200-amp electrical systems. It requires a 240V circuit and delivers 8 kW of heating power. This electric unit measures 16.6 inches wide and weighs 19 pounds. It provides a gas-free solution for users with sufficient electrical capacity.
Do any of these heaters include WiFi connectivity?
The Rheem RTG-84XLN and RTG-84XLP-3 models feature WiFi connectivity. This allows for remote management and monitoring of your hot water system. The Westinghouse APOLO-180K also offers smart connectivity for precise temperature control. These features let you adjust settings from your phone without accessing the unit directly.
What is the best option for RVs or single fixtures?
The Furrion 2021123985 is the top choice for RVs and single fixtures. It delivers 2.4 GPM, which is sufficient for compact spaces. Its compact size and gas-powered operation make it perfect for mobile or limited-use scenarios. It is not suitable for whole-house heating due to its low flow rate.
Which heater is best for indoor natural gas installation?
The Rheem RTG-84DVLN and Westinghouse APOLO-180K are designed for indoor use. The Rheem model provides 8.4 GPM with direct venting for large families. The Westinghouse unit offers 7.9 GPM with smart controls. Both units fit well in garages or utility rooms where gas lines are already installed.
How much space do these tankless heaters require?
Dimensions vary by model. The Stiebel Eltron Tempra 29 Plus is compact at 16.6 inches wide and 14.5 inches tall. The Rheem RTG-84DVLN measures 13.5 inches wide and 24.2 inches tall. The Westinghouse APOLO-180K is wider at 17.1 inches. Check your installation space before selecting a unit.