Best Rheem Tankless Water Heaters Under $1500 in 2026: 8 Picks
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Finding the best rheem tankless water heaters under $1500 requires matching specs to your home’s layout and fuel source. We compared 8 models strictly by published specifications to help you choose correctly. The Rheem RTG 9.5 GPM Natural Gas Water Heater leads this list. Its 9.5 GPM flow rate makes it ideal for large homes using indoor natural gas. This unit also features WiFi connectivity for precise digital control. The selections here are based on data from the listings, not personal testing. Use this guide to decide which flow rate, fuel type, and venting style fit your installation needs.
Quick picks
The best fit for you
- You want the best indoor natural gas model Rheem RTG 9.5 GPM Natural Gas Water Heater It delivers 9.5 GPM flow with WiFi control for indoor use.
- You need outdoor heating without venting ductwork Rheem RTG 9.5 GPM Outdoor Natural Gas Tankless Heater This unit provides 9.5 GPM and 199,900 BTUs for exterior installation.
- You want the lowest cost indoor natural gas option Rheem RTGH 9.0 GPM Natural Gas Tankless Heater It offers 9.0 GPM output and 0.93 UEF efficiency for indoor setups.
- You need outdoor propane with remote monitoring Rheem RTG 9.5 GPM Outdoor Propane Tankless Water Heater It supplies 9.5 GPM of propane hot water with WiFi features.
- You want the highest flow rate available Rheem IKONIC 10.1 GPM Propane Tankless Heater This model provides 10.1 GPM output for high-demand propane homes.
Our 8 picks
Rheem RTG 9.5 GPM Natural Gas Water Heater
Best for: large homes using indoor natural gas
- 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
The Rheem RTG Series is an indoor natural gas tankless water heater delivering up to 9.5 GPM at a 35°F rise with a 199,900 BTU output. It features a non-condensing direct vent design, a 0.82 Uniform Energy Factor, and built-in WiFi connectivity. You get digital temperature adjustments to within 1°F. It suits multi-bathroom households running three to four simultaneous hot water fixtures.
Pros
- Delivers up to 9.5 GPM at a 35°F temperature rise
- High heat capacity of 199,900 BTU/hr
- Built-in WiFi connectivity and digital LED temperature panel with ±1°F control
- 15-year heat exchanger and 5-year parts warranty coverage
Cons
- Non-condensing 0.82 UEF efficiency rating
- Requires indoor direct venting setup
- Requires professional installation
Good fit if
- You have a natural gas supply and space for an indoor wall mount.
- You run up to three or four hot water fixtures at the same time.
- You want integrated WiFi connectivity to monitor the heater.
Skip if
- You use liquid propane rather than natural gas.
- You need an outdoor-mounted water heater.
- You prefer a condensing unit with an efficiency rating above 0.82 UEF.
Verdict: Rheem RTG 9.5 GPM Indoor Natural Gas Tankless Heater delivers strong flow capacity and precise digital control for multi-bath indoor installations. It provides dependable high-output performance for homes with heavy natural gas demand.
Rheem RTG 9.5 GPM Outdoor Natural Gas Tankless Heater
Best for: multi-bathroom homes needing outdoor natural gas heating
- Fuel Type
- Natural Gas
- Flow Rate
- 9.5 GPM
- BTU
- 199,900 BTU/hr
- Installation Location
- Outdoor
- Temperature Control
- ±1°F
- Certification
- CSA
View on Amazon: Rheem RTG 9.5 GPM Outdoor Natural Gas Tankless Heater Affiliate link
This outdoor natural gas tankless water heater delivers up to 9.5 GPM at a 35°F temperature rise using a 199,900 BTU burner. Because you mount it outside, it eliminates the need for indoor venting ductwork. It has a 0.82 Uniform Energy Factor, precision ±1°F temperature adjustments via a digital LED panel, and built-in freeze protection. It suits your multi-bathroom home if you want high capacity without dedicating interior utility space to venting.
Pros
- Delivers up to 9.5 GPM at a 35°F rise with 199,900 BTU/hr output
- Outdoor wall-mount installation eliminates the need for vent ducting
- Digital LED control panel provides precision temperature control to ±1°F
- Features built-in freeze protection and flame failure safety systems
- Comes with 15-year heat exchanger and 5-year parts warranties
Cons
- Non-condensing 0.82 UEF rating is lower than condensing alternatives
- Designed strictly for exterior outdoor mounting
- Does not include built-in Wi-Fi connectivity
Good fit if
- You need sufficient flow for three to four simultaneous showers.
- You want to mount the unit outside to bypass indoor venting runs.
- You have an existing natural gas supply line.
Skip if
- You require an indoor-mounted water heater.
- You need a unit that runs on liquid propane.
- You want integrated Wi-Fi monitoring directly from the factory.
Verdict: Rheem RTG 9.5 GPM Outdoor Natural Gas Water Heater delivers substantial 199,900 BTU heating capacity for multi-bath homes while eliminating indoor venting requirements. Its outdoor design, precise digital controls, and integrated freeze protection make it a dependable exterior hot water solution.
Rheem RTGH 9.0 GPM Natural Gas Tankless Heater
Best for: multi-bathroom homes using indoor natural gas
- Fuel Type
- Natural Gas
- Flow Rate
- 9.0 GPM
- BTU
- 180,000 BTU/hr
- Installation Location
- Indoor
- Temperature Control
- ±1°F
- Certification
- CSA
View on Amazon: Rheem RTGH 9.0 GPM Natural Gas Tankless Heater Affiliate link
This indoor condensing natural gas unit delivers up to 9.0 GPM at a 35°F rise using 180,000 BTU/hr. Its 0.93 Uniform Energy Factor extracts extra heat from exhaust gases for efficient operation. You can run three to four fixtures simultaneously with digital temperature control accurate to 1°F. It suits multi-bathroom households that have an existing natural gas supply and space for direct-vent indoor mounting.
Pros
- Delivers up to 9.0 GPM flow rate at a 35°F rise
- Condensing design with 0.93 Uniform Energy Factor
- Digital LED temperature control accurate to ±1°F
- Built-in freeze protection system
- 15-year heat exchanger and 5-year parts warranty
Cons
- Configuration lacks built-in Wi-Fi connectivity
- Indoor installation only, requiring direct venting
Good fit if
- You have a natural gas connection and need up to 9.0 GPM for 3 to 4 showers.
- You want a high-efficiency condensing model with a 0.93 UEF rating.
- You need an indoor direct-vent unit with built-in freeze protection.
Skip if
- You use liquid propane rather than natural gas.
- You plan to mount your water heater outdoors.
- You require built-in Wi-Fi monitoring on your unit.
Verdict: Rheem RTGH 9.0 GPM Indoor Natural Gas Heater delivers 9.0 GPM with a 0.93 UEF rating for high-demand indoor setups. It provides precise temperature management and reliable multi-bath output on natural gas lines.
Rheem RTG 9.5 GPM Outdoor Propane Tankless Water Heater
Best for: large propane homes needing outdoor installation
- Fuel Type
- Liquid Propane
- Flow Rate
- 9.5 GPM
- BTU
- 199,900 BTU/hr
- Installation Location
- Outdoor
- Temperature Control
- ±1°F
- Certification
- CSA
View on Amazon: Rheem RTG 9.5 GPM Outdoor Propane Tankless Water Heater Affiliate link
This outdoor tankless water heater runs on liquid propane and delivers up to 9.5 GPM at a 35°F temperature rise using 199,900 BTU/hr. Because it mounts outdoors, you do not need dedicated indoor venting. It includes built-in Wi-Fi and digital temperature control with 1°F increments. This unit suits you if you have a multi-bathroom home set up for propane fuel and want exterior wall mounting.
Pros
- Delivers up to 9.5 GPM flow rate with a 199,900 BTU/hr burner
- Outdoor installation eliminates indoor venting requirements
- Built-in WiFi connectivity and digital LED temperature panel
- 15-year heat exchanger and 5-year parts warranty
Cons
- Requires liquid propane supply and cannot use natural gas
- Designed strictly for outdoor installation
- Non-condensing design with a 0.82 Uniform Energy Factor
Good fit if
- You have an exterior wall location that eliminates indoor exhaust venting.
- You use liquid propane as your primary fuel source.
- You need high flow capacity to supply up to four simultaneous showers.
Skip if
- You require an indoor installation.
- You use natural gas rather than liquid propane.
- You want a condensing unit with an efficiency rating above 0.82 UEF.
Verdict: Rheem RTG 9.5 GPM Outdoor Liquid Propane Tankless Heater provides high-volume propane hot water without the need for indoor venting ductwork. It offers remote Wi-Fi monitoring and dependable whole-home capacity for outdoor installations.
Rheem RTGH 9.0 GPM Indoor Propane Tankless Water Heater
Best for: indoor multi-bath homes running on liquid propane
- Fuel Type
- Liquid Propane
- Flow Rate
- 9.0 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 RTGH 9.0 GPM Indoor Propane Tankless Water Heater Affiliate link
This indoor condensing tankless water heater runs on liquid propane and delivers up to 9.0 GPM at a 35°F temperature rise using 180,000 BTU/hr. Its 0.93 Uniform Energy Factor provides high combustion efficiency through a direct-vent system. You get precise ±1°F digital temperature adjustments. It suits medium to large households needing enough flow to run three to four showers at the same time on propane fuel.
Pros
- 9.0 GPM maximum flow rate at 35°F temperature rise
- 0.93 Uniform Energy Factor condensing operation
- 15-year heat exchanger and 5-year parts warranty coverage
- Precise digital LED temperature control within ±1°F
Cons
- Requires liquid propane supply rather than natural gas
- Does not include built-in Wi-Fi connectivity
- Requires dedicated indoor direct venting
Good fit if
- You use liquid propane and need up to 9.0 GPM for multiple bathrooms.
- You want high-efficiency condensing performance with a 0.93 UEF rating.
- You need an indoor direct-vent unit with precise digital temperature control.
Skip if
- You have a natural gas connection instead of liquid propane.
- You plan to install the water heater outdoors.
- You want wireless connectivity or app controls out of the box.
Verdict: Rheem RTGH 9.0 GPM Indoor Propane Tankless Heater provides high-efficiency condensing performance for propane-powered homes requiring steady output across three to four fixtures. It delivers strong flow and tight temperature control without requiring outdoor placement.
Rheem IKONIC 10.1 GPM Propane Tankless Heater
Best for: High-flow propane homes with app needs
- Fuel Type
- Liquid Propane
- Flow Rate
- 10.1 GPM
- Installation Location
- Indoor
- Dimensions
- 28.6 x 17.3 x 13.7 inches
- Features
- WiFi
- Weight
- 77.6 pounds
View on Amazon: Rheem IKONIC 10.1 GPM Propane Tankless Heater Affiliate link
This Rheem unit delivers 10.1 GPM of hot water using liquid propane. It features a 180,000 BTU burner and ultra-low NOx emissions. Built-in EcoNet Wi-Fi lets you track usage and control temperature from your phone. The compact design requires only ½ inch side clearance. It is suitable for indoor installation or outdoor use with a conversion kit.
Pros
- 10.1 GPM flow rate
- 180,000 BTU heating capacity
- Built-in EcoNet Wi-Fi
- Ultra-low NOx emissions
- Outdoor installation capable with kit
Cons
- Liquid propane fuel only
- No recirculation loop included
- Heavier than non-condensing models
Good fit if
- You need high flow for multiple bathrooms
- You have a propane supply
- You want remote monitoring via app
Skip if
- You use natural gas
- You need built-in recirculation
- You lack outdoor conversion kit
Verdict: Rheem IKONIC 10.1 GPM Propane suits large homes needing high output and smart controls. It fits propane users who value efficiency and remote management.
Rheem IKONIC 8.4 GPM Natural Gas Water Heater
Best for: indoor natural gas tank retrofits
- Fuel Type
- Natural Gas
- Flow Rate
- 8.4 GPM
- BTU
- 157,000 BTUs
- Installation Location
- Indoor
- Dimensions
- 28.6 x 17.3 x 13.7 inches
- Weight
- 77.6 pounds
View on Amazon: Rheem IKONIC 8.4 GPM Natural Gas Water Heater Affiliate link
This indoor tankless water heater delivers up to 8.4 GPM using natural gas and a 157,000 BTU burner. It features dual heat exchangers and supports half-inch gas line connections for straightforward tank retrofits. The unit vents through room air intake or flex venting setups. You will find this model ideal if you need continuous whole-home hot water for simultaneous fixtures without upgrading gas supply piping.
Pros
- Delivers up to 8.4 GPM flow rate with a 157,000 BTU burner
- Compatible with standard 1/2-inch gas lines for retrofits
- Condensing dual heat exchangers maximize heat transfer
- Supports flex venting, room air intake, and common venting
- Includes a 15-year limited warranty
Cons
- Indoor installation only
- Operates exclusively on natural gas rather than propane
- Weighs 77.6 pounds, requiring reinforced wall mounting
Good fit if
- You need up to 8.4 GPM of indoor hot water using natural gas.
- You plan to replace a tank unit using existing 1/2-inch gas piping.
- You require versatile venting options such as flex venting or room air intake.
Skip if
- You require an outdoor installation or liquid propane fuel source.
- You need higher flow rates above 8.4 GPM for simultaneous high-volume demands.
Verdict: Rheem IKONIC 8.4 GPM Indoor Natural Gas Water Heater provides continuous hot water via a 157,000 BTU condensing dual heat exchanger system. Its flexible venting and 1/2-inch gas line compatibility make it a practical choice for indoor tank replacements.
Rheem Professional Classic 50-Gallon Propane Water Heater
Best for: propane homes needing dedicated 50-gallon tank storage
- Fuel Type
- Liquid Propane
- Capacity
- 50 gallons
- Dimensions
- 50 x 20 x 20 inches
View on Amazon: Rheem Professional Classic 50-Gallon Propane Water Heater Affiliate link
The Rheem Professional Classic is a 50-gallon liquid propane storage water heater designed for floor installation. It features a 36,000 BTU burner and dimensions of 50 inches tall by 20 inches wide and deep. Built-in elements include an EverKleen sediment system, match-free ignition, and an R-Tech anode rod for tank maintenance. This model suits you if your home relies on liquid propane and requires dedicated 50-gallon stored capacity.
Pros
- 50-gallon storage capacity with 36,000 BTU heating output
- EverKleen system helps fight sediment buildup
- Match-free ignition system for easier lighting
- R-Tech anode rod provides long-lasting tank protection
- Meets 40 ng/J low-NOx eco-friendly burner standards
Cons
- Large floor footprint measuring 50 by 20 by 20 inches
- Stores a fixed 50 gallons rather than providing tankless flow
- Compatible only with liquid propane connections
Good fit if
- You want a dedicated 50-gallon tank fueled by liquid propane.
- You have floor space measuring at least 50 by 20 by 20 inches.
Skip if
- You need a compact tankless design to save floor space.
- You use natural gas instead of liquid propane.
Verdict: Rheem Professional Classic 50-Gallon Propane Water Heater delivers dedicated 50-gallon storage with low-NOx propane combustion. It suits installations where you prefer a conventional tank over a wall-hung unit.
Specifications side by side
| Spec | Rheem RTG 9.5 GPM Natural Gas Water Heater | Rheem RTG 9.5 GPM Outdoor Natural Gas Tankless Heater | Rheem RTGH 9.0 GPM Natural Gas Tankless Heater | Rheem RTG 9.5 GPM Outdoor Propane Tankless Water Heater | Rheem RTGH 9.0 GPM Indoor Propane Tankless Water Heater | Rheem IKONIC 10.1 GPM Propane Tankless Heater | Rheem IKONIC 8.4 GPM Natural Gas Water Heater | Rheem Professional Classic 50-Gallon Propane Water Heater |
|---|---|---|---|---|---|---|---|---|
| Fuel Type | Natural Gas | Natural Gas | Natural Gas | Liquid Propane | Liquid Propane | Liquid Propane | Natural Gas | Liquid Propane |
| Flow Rate | 9.5 GPM | 9.5 GPM | 9.0 GPM | 9.5 GPM | 9.0 GPM at 35°F rise | 10.1 GPM | 8.4 GPM | not stated |
| BTU | 199,900 BTU/hr | 199,900 BTU/hr | 180,000 BTU/hr | 199,900 BTU/hr | 180,000 BTU/hr | not stated | 157,000 BTUs | not stated |
| Installation Location | Indoor | Outdoor | Indoor | Outdoor | Indoor | Indoor | Indoor | not stated |
| Capacity | not stated | not stated | not stated | not stated | not stated | not stated | not stated | 50 gallons |
| Temperature Control | ±1°F | ±1°F | ±1°F | ±1°F | Digital LED, ±1°F | not stated | not stated | not stated |
| Certification | CSA | CSA | CSA | CSA | CSA | not stated | not stated | not stated |
| Dimensions | 24.2 x 13.5 x 10.3 inches | 20.8 x 13.5 x 9.4 inches | 23.7 x 17.7 x 9.8 inches | 20.8 x 13.5 x 9.4 inches | 23.7 x 17.7 x 9.8 inches | 28.6 x 17.3 x 13.7 inches | 28.6 x 17.3 x 13.7 inches | 50 x 20 x 20 inches |
| Venting Type | Non-Condensing | Non-Condensing | not stated | Non-Condensing | not stated | not stated | not stated | not stated |
| Features | WiFi | WiFi | WiFi | WiFi | WiFi | WiFi | not stated | not stated |
| Weight | 46.5 pounds | 39.3 pounds | 59.9 pounds | 40.5 pounds | 59.9 pounds | 77.6 pounds | 77.6 pounds | not stated |
| Size | 9.5 GPM (WiFi) | 9.5 GPM (No WiFi) | 9.0 GPM (No WiFi) | 9.5 GPM (WiFi) | 9.0 GPM (Without WiFi) | 10.1 GPM (no Recirc) | 8.4 GPM | Tall |
| Color | Gray | Gray | Gray | Gray | Gray | Gray | Gray | Gray |
| Model | RTG-95DVELN-3 | RTG-95XLN-3 | RTGH-90DVLN-3 | RTG-95XELP-3 | RTGH-90DVLP-3 | RECTGH-S10iP | RECTGH-S84iN | PROG50-36P RH62 |
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Key Specs for Choosing Rheem Units
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Match fuel to your supply
Check your home’s gas line before buying. The Rheem RTG 9.5 GPM Natural Gas Water Heater requires a natural gas connection. If you use propane, select the Rheem RTG 9.5 GPM Outdoor Propane Tankless Water Heater instead. Using the wrong fuel type will prevent the unit from operating. Verify your supply source matches the product’s fuel specification exactly. Do not attempt to convert between natural gas and propane without professional modification.
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Select indoor or outdoor fit
Your installation space dictates the model. Indoor units like the Rheem RTG 9.5 GPM Natural Gas Water Heater need proper ventilation and clearance. Outdoor models, such as the Rheem RTG 9.5 GPM Outdoor Natural Gas Tankless Heater, handle weather elements. Choose outdoor units if you lack indoor venting space. Indoor units often require more complex ductwork. Ensure your chosen location meets the manufacturer’s clearance and environmental requirements for safe operation.
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Verify venting requirements
Venting type affects installation complexity. Most models here use non-condensing venting, which is standard for natural gas. The Rheem IKONIC 8.4 GPM Natural Gas Water Heater uses a condensing system, which may allow flexible venting options. Condensing units often achieve higher efficiency ratings. Check if your existing venting supports the chosen unit type. Non-condensing units typically require specific chimney or wall vent configurations. Match the venting type to your home’s existing infrastructure to avoid costly retrofits.
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Check WiFi connectivity needs
Remote monitoring is available on select models. The Rheem RTG 9.5 GPM Natural Gas Water Heater includes WiFi for digital control. Some versions, like the outdoor natural gas model, may lack this feature. If you want to adjust settings remotely, verify the specific model includes WiFi. This feature allows you to monitor performance and temperature from your phone. Decide if smart connectivity is essential for your daily routine before purchasing.
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Confirm flow rate capacity
Flow rate determines simultaneous usage. Most units here deliver 9.0 to 9.5 GPM, supporting multiple bathrooms. The Rheem IKONIC 10.1 GPM Propane Tankless Heater offers higher capacity for large homes. If you run three or more fixtures at once, ensure the GPM rating meets your peak demand. Lower flow rates may result in reduced pressure during heavy use. Compare the GPM spec against your household’s total hot water needs.
Frequently asked questions
Which Rheem tankless heater has the highest flow rate?
The Rheem IKONIC 10.1 GPM Propane model offers the highest flow rate at 10.1 gallons per minute. This unit is designed for large homes requiring substantial hot water volume. It operates on propane and features WiFi connectivity for remote management. The indoor installation requires a specific venting setup, and the unit weighs 77.6 pounds.
Can I install these units without outdoor venting?
Yes, several indoor models handle venting internally or use different ductwork requirements. The Rheem RTG 9.5 GPM Natural Gas Indoor model uses non-condensing venting. The Rheem RTGH 9.0 GPM Indoor Natural Gas Heater also supports indoor placement. These units allow you to avoid exterior wall penetrations, making them suitable for interior closets or utility rooms.
Do all Rheem tankless models include WiFi control?
Most models on this list include WiFi features for remote monitoring and control. The Rheem RTG 9.5 GPM Natural Gas Indoor unit, the outdoor natural gas version, and the propane models all list WiFi as a feature. However, the Rheem IKONIC 8.4 GPM Natural Gas model does not list WiFi in its attributes. You should check the specific model details before purchasing.
What is the difference between the RTG and RTGH models?
The RTG series typically includes both indoor and outdoor variants with non-condensing venting options. The RTGH series focuses on indoor installations. For example, the RTGH 9.0 GPM Indoor Natural Gas Heater provides 0.93 UEF efficiency. The RTG 9.5 GPM Indoor model delivers slightly higher flow at 9.5 GPM. Both series offer digital controls and WiFi connectivity for user convenience.
Is the IKONIC 10.1 GPM Propane model heavy?
Yes, the Rheem IKONIC 10.1 GPM Propane unit weighs 77.6 pounds. It measures 17.3 inches in width, 28.6 inches in height, and 13.7 inches in length. This weight and size are larger than the standard RTG series units. You need a sturdy mounting surface for indoor installation. The unit is designed for high-flow demands in larger households.
Which model is best for a home with four bathrooms?
The Rheem RTG 9.5 GPM Natural Gas Water Heater is ideal for large homes with multiple bathrooms. It delivers 9.5 GPM of hot water, supporting simultaneous fixture use. The outdoor propane version also provides 9.5 GPM for exterior installation. These high-flow models ensure consistent temperature and pressure across multiple outlets in busy households.