Rheem RTGH Series 8.4 GPM Natural Gas Tankless Water Heater Alternatives: 6 Similar Picks Compared
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The rheem rtgh series 8 4 gpm natural gas tankless water heater delivers high efficiency and precise temperature control for indoor whole-house use. It features a compact design and condensing technology that reduces energy consumption. This unit suits large families needing consistent hot water for multiple simultaneous showers.
You might look for alternatives if you need outdoor installation, propane fuel, or different flow rates. Some buyers prefer non-condensing models for simpler venting or want recirculation features for instant hot water. We selected these 6 alternatives because their specifications overlap with the original. Each pick matches key metrics like fuel type, installation location, or flow capacity to help you find the right fit.
Our top pick: Rheem RTGH 8.4 GPM Indoor Natural Gas Heater.
How each alternative compares
Rheem IKONIC 8.4 GPM Natural Gas
The Rheem IKONIC 8.4 GPM Natural Gas model adds recirculation capability, which the original RTGH lacks. This feature lets you pre-warm pipes for faster hot water delivery at the tap. It is slightly taller at 28.6 inches and weighs 86 pounds, making it heavier than the original 59.9-pound unit. Both share the 8.4 GPM flow rate and indoor natural gas operation. The IKONIC suits homes that want on-demand hot water without waiting, prioritizing convenience over the slimmer profile of the standard RTGH. It keeps the same high efficiency and WiFi connectivity for remote monitoring and control.
Rheem RTG 9.5 GPM Natural Gas Water Heater
The Rheem RTG 9.5 GPM Natural Gas model offers a higher flow rate of 9.5 GPM compared to the original 8.4 GPM. This extra capacity supports more simultaneous showers or appliances in very large households. It uses non-condensing technology, which differs from the original condensing design, potentially affecting efficiency and venting requirements. The unit is lighter at 46.5 pounds and narrower at 13.5 inches wide. It includes WiFi features for smart control. If your home demands maximum water volume during peak usage times, this higher-flow option provides better performance, though it may consume more gas per hour than the original.
Westinghouse 9.2 GPM Indoor Natural Gas Tankless Heater
The Westinghouse 9.2 GPM Indoor Natural Gas Tankless Heater provides a higher flow rate of 9.2 GPM than the original 8.4 GPM unit. It features WiFi connectivity for smart management, similar to the original. The Westinghouse model is wider at 15.9 inches and deeper at 15.9 inches, taking up more wall space than the original 9.8-inch depth. It weighs 56.7 pounds, which is slightly lighter than the original. This unit is ideal for large homes needing strong flow and digital control. It trades the original’s specific condensing efficiency for higher capacity and a different footprint. Choose this if you prioritize flow volume and smart features over the original’s compact dimensions.
Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater
The Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater is designed for outdoor installation, unlike the original indoor model. It uses non-condensing technology, which changes its efficiency profile and venting needs. The outdoor unit is significantly smaller, measuring 20.8 inches in height and weighing only 39.3 pounds. It shares the 8.4 GPM flow rate and WiFi connectivity. This model suits buyers who lack indoor venting space or prefer to keep the unit outside. It offers the same hot water capacity but requires different installation conditions. If your home has suitable outdoor placement and venting, this option saves indoor space while maintaining comparable performance.
Rheem RTGH Series 8.4 GPM Indoor Propane
The Rheem RTGH Series 8.4 GPM Indoor Propane model uses propane instead of natural gas. It shares the exact same dimensions and weight as the original natural gas unit, measuring 23.7 inches high and 59.9 pounds. It maintains the 8.4 GPM flow rate and indoor condensing technology. The key difference is the fuel source, requiring a propane tank or supply line. This unit suits homes with propane access but no natural gas line. It offers identical performance metrics and size, making it a direct swap for fuel type. Choose this if you need the same compact, high-efficiency indoor performance but rely on propane for heating.
Rheem 8.4 GPM Indoor Propane Tankless Water Heater
The Rheem 8.4 GPM Indoor Propane Tankless Water Heater uses propane fuel, differing from the original natural gas model. It employs non-condensing technology, which contrasts with the original’s condensing design. This unit shares the 8.4 GPM flow rate and WiFi connectivity. It is lighter at 46.5 pounds and narrower at 13.5 inches wide compared to the original. The non-condensing design may impact efficiency and venting requirements. This model fits homes with propane access that prefer a smaller, lighter unit. It offers reliable hot water delivery without the added weight and complexity of condensing technology. Select this if you prioritize a compact form factor and have propane available.
Quick picks
Our 7 picks
Rheem RTGH 8.4 GPM Indoor Natural Gas Heater
Best for: large families needing whole-house hot water
- Fuel Type
- Natural Gas
- Flow Rate
- 8.4 GPM
- BTU
- 157,000 BTU/hr
- Installation Location
- Indoor
- Temperature Control
- ±1°F
- Certification
- CSA
View on Amazon: Rheem RTGH 8.4 GPM Indoor Natural Gas Heater Affiliate link
This indoor natural gas unit delivers 8.4 GPM at a 35°F rise, powered by 157,000 BTUs. It features industry-leading condensing technology with a 0.93 Uniform Energy Factor for high efficiency. The digital LED control offers precision within ±1°F. It is designed for whole-house use, supporting three to four simultaneous showers. Professional installation is recommended for this CSA-certified model.
Pros
- 8.4 GPM flow rate for whole-house demand
- 0.93 Uniform Energy Factor for ultra-low gas bills
- Digital LED control with ±1°F precision
- 15-year heat exchanger warranty
Cons
- Indoor installation only
- No WiFi connectivity in this specific 8.4 GPM model
- Requires professional installation
Good fit if
- You need high-efficiency indoor heating for a large family
- You want precise temperature control within ±1°F
- You prefer natural gas over propane
Skip if
- You require outdoor installation capabilities
- You need smart WiFi connectivity
- You have limited indoor space for a 23.7-inch height unit
Verdict: Rheem RTGH 8.4 GPM Indoor Natural Gas is the best overall pick for large households seeking high efficiency and precise temperature control. It suits buyers who prioritize energy savings and whole-house performance over smart features.
Rheem IKONIC 8.4 GPM Natural Gas
Best for: Indoor homes wanting WiFi control
- Fuel Type
- Natural Gas
- Flow Rate
- 8.4 GPM
- BTU
- 157,000 BTU/hr
- Installation Location
- Indoor
- Dimensions
- 28.6 x 17.3 x 13.7 inches
- Features
- WiFi
View on Amazon: Rheem IKONIC 8.4 GPM Natural Gas Affiliate link
This Rheem IKONIC unit delivers 8.4 GPM of hot water using natural gas. It features 157,000 BTUs and WiFi connectivity for remote control. The indoor design includes built-in recirculation to save water. You get flexible venting options and compatibility with existing ½” gas lines. This model suits homes needing high efficiency and smart management for indoor installation.
Pros
- 8.4 GPM flow rate with recirculation
- 157,000 BTU/hr heating capacity
- Built-in WiFi for remote control
- Flexible venting and room air intake
Cons
- Heavier build at 86 pounds
- Larger footprint than standard units
- Indoor installation only
Good fit if
- You need smart control via WiFi
- You want to save water with recirculation
- You have an indoor space for venting
Skip if
- You require outdoor installation
- You need propane fuel
- You prefer a lighter unit
Verdict: Rheem IKONIC 8.4 GPM Natural Gas is a high-efficiency indoor heater for users who value WiFi control and water savings. It fits homes with existing gas lines and indoor venting space.
Rheem RTG 9.5 GPM Natural Gas Water Heater
Best for: high-flow whole-house indoor use
- Fuel Type
- Natural Gas
- Flow Rate
- 9.5 GPM
- BTU
- 199,900 BTU/hr
- Installation Location
- Indoor
- Temperature Control
- ±1°F
- Certification
- CSA
View on Amazon: Rheem RTG 9.5 GPM Natural Gas Water Heater Affiliate link
This Rheem RTG unit delivers 9.5 GPM at a 35°F rise, powered by 199,900 BTUs. It is designed for indoor use with non-condensing venting. You get precise digital temperature control within ±1°F. The unit includes WiFi connectivity for remote monitoring. It fits whole-house needs for 3-4 simultaneous showers. This model replaces standard tank heaters efficiently.
Pros
- 9.5 GPM flow rate for high demand
- 199,900 BTU/hr output capacity
- WiFi enabled for remote control
- Precision ±1°F temperature adjustment
- CSA certified safety standards
Cons
- Indoor-only installation requires venting
- Non-condensing design has lower efficiency than condensing models
- Requires professional installation
Good fit if
- You need high flow for multiple bathrooms
- You want WiFi monitoring capabilities
- You have indoor venting access
Skip if
- You need outdoor installation
- You prefer condensing efficiency
- You want DIY setup
Verdict: Rheem RTG 9.5 GPM Natural Gas suits large households needing high flow and smart features. It delivers consistent hot water for multiple simultaneous uses. This unit is ideal for homes with existing indoor venting infrastructure.
Westinghouse 9.2 GPM Indoor Natural Gas Tankless Heater
Best for: large homes needing smart high-flow control
- Fuel Type
- Natural Gas
- Flow Rate
- 10.3 GPM
- BTU
- 199,000 BTU
- Installation Location
- Indoor
- Temperature Control
- ±1.8°F
- Certification
- CSA
View on Amazon: Westinghouse 9.2 GPM Indoor Natural Gas Tankless Heater Affiliate link
This Westinghouse indoor tankless water heater delivers 9.2 GPM at 199,000 BTU on natural gas. It features smart WiFi app control and maintains temperature stability within ±1.8°F. The unit includes integrated freeze protection down to -13°F and a copper heat exchanger. It measures 24.8 x 15.9 x 15.9 inches and weighs 56.7 pounds. This model suits homes needing high flow rates with digital management capabilities.
Pros
- 9.2 GPM flow rate for whole-home use
- Smart WiFi app and voice control
- Precise ±1.8°F temperature stability
- Freeze protection down to -13°F
Cons
- Larger footprint than standard 8.4 GPM models
- Requires specific 3x5 inch double-wall venting
- No physical display mentioned in data
Good fit if
- You need high flow for multiple bathrooms
- You want remote app control
- You have proper venting space
Skip if
- You require propane fuel
- You need outdoor installation
- You prefer compact dimensions
Verdict: Westinghouse 9.2 GPM Indoor Gas Heater offers high capacity and smart features for large households. It fits buyers who prioritize digital control and winter reliability over a smaller footprint.
Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater
Best for: outdoor whole-house hot water needs
- 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 a 35°F rise using 180,000 BTUs of natural gas. It features a non-condensing design that eliminates the need for complex venting. The digital LED panel allows precision temperature adjustments within ±1°F. You get built-in freeze protection and flame failure safety. This model suits homes needing whole-house hot water without indoor installation constraints.
Pros
- 8.4 GPM flow rate for 3-4 simultaneous showers
- 180,000 BTU/hr output for high performance
- Outdoor installation saves indoor space
- Non-condensing design requires no special venting
- Digital LED control with ±1°F precision
Cons
- Outdoor installation only
- Non-condensing design has lower efficiency than condensing models
- No smart connectivity features included
Good fit if
- You need an outdoor unit to save indoor space
- You want high flow rates for multiple bathrooms
- You prefer simple non-condensing venting
Skip if
- You require indoor installation
- You need smart home integration
- You want the highest possible energy efficiency
Verdict: Rheem RTG 8.4 GPM Outdoor Gas Heater provides robust performance for outdoor setups. It fits buyers who prioritize flow rate and simple venting over smart features or indoor placement.
Rheem RTGH Series 8.4 GPM Indoor Propane
Best for: Indoor propane whole-house heating
- Fuel Type
- Liquid Propane
- Flow Rate
- 8.4 GPM at 35°F rise
- BTU
- 157,000 BTU/hr
- Installation Location
- Indoor
- Temperature Control
- Digital LED, ±1°F
- Certification
- CSA
View on Amazon: Rheem RTGH Series 8.4 GPM Indoor Propane Affiliate link
This indoor liquid propane unit delivers 8.4 GPM at a 35°F rise. It uses 157,000 BTU/hr with condensing technology for a 0.93 UEF. The digital LED control offers ±1°F precision. It fits homes needing whole-house hot water. The compact design suits tight utility spaces. It is ideal for large families requiring multiple simultaneous showers.
Pros
- 8.4 GPM flow rate for whole-house use
- 0.93 UEF efficiency rating
- Digital LED control with ±1°F precision
- Indoor direct vent installation
Cons
- Indoor installation requires venting
- No WiFi connectivity
- 5-year parts warranty
Good fit if
- You need indoor propane heating
- You want high efficiency
- You need precise temperature control
Skip if
- You require outdoor installation
- You need WiFi features
- You use natural gas
Verdict: Rheem RTGH 8.4 GPM Propane delivers high efficiency and precise temperature control for indoor propane setups. It suits large households needing reliable whole-house hot water without smart features.
Rheem 8.4 GPM Indoor Propane Tankless Water Heater
Best for: propane whole-house hot water
- Fuel Type
- Liquid Propane
- Flow Rate
- 8.4 GPM at 35°F rise
- BTU
- 180,000 BTU/hr
- Installation Location
- Indoor
- Temperature Control
- Digital LED, ±1°F
- Certification
- CSA
View on Amazon: Rheem 8.4 GPM Indoor Propane Tankless Water Heater Affiliate link
This indoor unit delivers 8.4 GPM at a 35°F rise using liquid propane. It features a 180,000 BTU/hr output and a 0.82 Uniform Energy Factor. The digital LED panel allows ±1°F temperature adjustments. Its compact 24.2-inch height fits standard wall spaces. It suits homes needing whole-house hot water without tank storage.
Pros
- 8.4 GPM flow rate for multiple showers
- 180,000 BTU/hr heating capacity
- ±1°F digital temperature precision
- 0.82 Uniform Energy Factor efficiency
- Space-saving wall-mount design
Cons
- Indoor installation only
- No WiFi connectivity in this model
- Requires professional installation
Good fit if
- You use liquid propane for fuel
- You need whole-house hot water capacity
- You want precise temperature control
Skip if
- You require outdoor installation
- You need smart WiFi features
- You prefer natural gas fuel
Verdict: Rheem RTG 8.4 GPM Propane offers reliable high-flow heating for propane-powered homes. It fits households prioritizing steady hot water delivery and precise temperature management over smart connectivity.
Specifications side by side
| Spec | Rheem RTGH 8.4 GPM Indoor Natural Gas Heater | Rheem IKONIC 8.4 GPM Natural Gas | Rheem RTG 9.5 GPM Natural Gas Water Heater | Westinghouse 9.2 GPM Indoor Natural Gas Tankless Heater | Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater | Rheem RTGH Series 8.4 GPM Indoor Propane | Rheem 8.4 GPM Indoor Propane Tankless Water Heater |
|---|---|---|---|---|---|---|---|
| Fuel Type | Natural Gas | Natural Gas | Natural Gas | Natural Gas | Natural Gas | Liquid Propane | Liquid Propane |
| Flow Rate | 8.4 GPM | 8.4 GPM | 9.5 GPM | 10.3 GPM | 8.4 GPM | 8.4 GPM at 35°F rise | 8.4 GPM at 35°F rise |
| BTU | 157,000 BTU/hr | 157,000 BTU/hr | 199,900 BTU/hr | 199,000 BTU | 180,000 BTU/hr | 157,000 BTU/hr | 180,000 BTU/hr |
| Installation Location | Indoor | Indoor | Indoor | Indoor | Outdoor | Indoor | Indoor |
| Temperature Control | ±1°F | not stated | ±1°F | ±1.8°F | ±1°F | Digital LED, ±1°F | Digital LED, ±1°F |
| Certification | CSA | not stated | CSA | CSA | CSA | CSA | CSA |
| Dimensions | 23.7 x 17.7 x 9.8 inches | 28.6 x 17.3 x 13.7 inches | 24.2 x 13.5 x 10.3 inches | not stated | 20.8 x 13.5 x 9.4 inches | 23.7 x 17.7 x 9.8 inches | 24.2 x 13.5 x 10.3 inches |
| Use | not stated | not stated | not stated | Whole House | not stated | not stated | not stated |
| Venting Type | not stated | not stated | Non-Condensing | not stated | Non-Condensing | not stated | Non-Condensing |
| Features | WiFi | WiFi | WiFi | WiFi | WiFi | WiFi | WiFi |
| Weight | 59.9 pounds | 86 pounds | 46.5 pounds | 56.7 pounds | 39.3 pounds | 59.9 pounds | 46.5 pounds |
| Size | 8.4 GPM (No WiFi) | 8.4 GPM (w Recirc) | 9.5 GPM (WiFi) | not stated | 8.4 GPM (No WiFi) | 8.4 GPM (Without WiFi) | 8.4 GPM (No WiFi) |
| Color | Gray | Gray | Gray | Grey 103NI | Gray | Gray | Gray |
| Model | RTGH-84DVLN-3 | RECTGH-SR84iN | RTG-95DVELN-3 | HW199A0G-NG | RTG-84XLN-3 | RTGH-84DVLP-3 | RTG-84DVLP-3 |
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Frequently asked questions
Can I install the Rheem RTGH 8.4 GPM outdoors?
No, the Rheem RTGH 8.4 GPM Natural Gas model is designed strictly for indoor installation. If you need an outdoor unit with similar flow, consider the Rheem RTG 8.4 GPM Outdoor Natural Gas Tankless Heater. That model is built to withstand exterior conditions while providing the same 8.4 GPM capacity you require.
Does the Rheem RTGH support WiFi connectivity?
Yes, the Rheem RTGH 8.4 GPM Indoor Natural Gas Heater includes WiFi capabilities. This allows you to monitor and control the unit remotely. You can adjust settings and check status from your smartphone, ensuring precise temperature management without needing to access the physical unit directly.
What is the weight of the Rheem RTGH 8.4 GPM?
The Rheem RTGH 8.4 GPM Indoor Natural Gas Heater weighs 59.9 pounds. It measures 17.7 inches wide, 23.7 inches high, and 9.8 inches long. This compact footprint makes it suitable for tight indoor spaces, though you should ensure your mounting surface can support this weight.
Is there a propane version of the Rheem RTGH 8.4 GPM?
Yes, Rheem offers a propane alternative with the same 8.4 GPM flow rate. The Rheem RTGH Series 8.4 GPM Indoor Propane model shares identical dimensions and weight with the natural gas version. It is also designed for indoor installation and includes WiFi features for remote control.
Which alternative offers a higher flow rate than 8.4 GPM?
The Rheem RTG 9.5 GPM Natural Gas Water Heater provides a higher flow rate of 9.5 GPM. It is also available in an outdoor configuration. This model suits large households needing more simultaneous hot water. It includes WiFi for smart control and non-condensing venting for indoor use.
Can I use the Rheem IKONIC for recirculation?
Yes, the Rheem IKONIC 8.4 GPM Natural Gas model supports recirculation. This feature helps deliver hot water faster by keeping pipes warm. It weighs 86 pounds and stands 28.6 inches tall. The unit includes WiFi for remote management, making it a premium choice for indoor homes.
Does the Westinghouse 9.2 GPM model have WiFi?
Yes, the Westinghouse 9.2 GPM Indoor Natural Gas Tankless Heater includes WiFi. It offers high capacity for large homes and features digital control. The unit weighs 56.7 pounds and measures 15.9 inches wide and 24.8 inches high. It is designed for reliable performance in winter conditions.