8 Best rinnai tankless water heaters of 2025

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1

Rinnai
Rinnai RU199iN Condensing Tankless Hot Water Heater, 11 GPM, Natural Gas, Indoor Installation
Main highlights

Unlimited Hot Water Flow
Provides endless hot water with a flow rate of 11 GPM.

Ideal for Large Households
Perfect for homes needing simultaneous hot water for multiple appliances.

Highly Praised Efficiency
Customers love the efficient and quiet operation with minimal delays.
Key specs
- special features:Endless Hot Water
- maximum flow rate:11 GPM
- wattage:N/A
- voltage:120 Volts
- heat output:N/A
9.7

Exceptional

Our Rating

9.5
Long life

9.1
Temperature control

9.1
Comfort
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Value for Money

2

Rinnai
NEW Rinnai CX199iN High Efficiency Plus Natural Gas Interior Tankless Water Heater, Up to 11 GPM
Main highlights

Super High Efficiency 96
Achieve significant energy savings with a 96% efficiency rating, perfect for eco-conscious households.

Indoor Outdoor Versatility
Ideal for both indoor and outdoor installations, offering flexible placement options.

Smart Connect App Praise
Highly praised for its user-friendly app, simplifying setup and troubleshooting.
9.6

Exceptional

Our Rating
3

Rinnai
NEW Rinnai RX199iN Condensing Smart Sense Natural Gas or Propane Tankless Water Heater, Indoor or Outdoor Water Heater, Up to 11.1 GPM, 199,000 BTU
Main highlights

Versatile Installation
Install indoors or outdoors with Smart Sense gas control.

Ideal for Large Households
Supports up to 7 fixtures simultaneously with 11.1 GPM.

Endless Hot Water
Customers praise its ability to provide continuous hot water.
Key specs
- special features:Indoor/outdoor install
- maximum flow rate:11.1 GPM
- wattage:N/A
- voltage:N/A
- heat output:N/A
9.5

Excellent

Our Rating

8.0
Easy installation

8.0
Temperature control
4

Rinnai
Rinnai RE180iN Non-Condensing Natural Gas Tankless Water Heater, Up to 8.5 GPM, Indoor Installation, 180,000 BTU
Main highlights

Key Features
Energy-efficient, tankless design heats water on demand. Features LED screen for easy monitoring. Offers up to 6.9 GPM for simultaneous use across 5 fixtures.

Ideal Use Cases
Perfect for small to medium-sized homes needing uninterrupted hot water supply for multiple fixtures. Optimal in regions matching its temperature capabilities.

Customer Praise
Reviewers consistently highlight its reliability and the significant energy savings experienced, alongside the convenience of never running out of hot water.
Key specs
- special features:LED Display
- maximum flow rate:6.9 GPM
- wattage:18 KW
- voltage:N/A
- heat output:N/A
9.4

Excellent

Our Rating
5

Rinnai
Rinnai RUCS65IN Tankless Hot Water Heater, 6.5 GPM, Natural Gas, Indoor Installation

20% Off
Main highlights

Unlimited Hot Water Flow
Enjoy endless hot water with a compact, durable design.

Ideal for Multiple Appliances
Serves up to 5 appliances simultaneously with 6.5 GPM flow.

Ease of Maintenance
Easy part replacement and maintenance praised by customers.
9.1

Excellent

Our Rating

9.3
Efficient Energy Use

8.7
worth the money

8.0
Temperature control
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6

Rinnai
Rinnai RSC160iN Smart-Circ Condensing Gas Tankless Water Heater, Super High Efficiency Plus Natural Gas Water Heater, Up to 9 GPM, Indoor Installation, 160,000 BTU

17% Off
Main highlights

Smart-Circ Technology Efficiency
Learns water usage patterns for energy efficiency and convenience.

Ideal for Large Households
Perfect for homes needing simultaneous hot water in multiple fixtures.

Customer Praised Recirculation
Recirculating pump saves water and ensures immediate hot water access.
Key specs
- special features:Smart-Circ technology
- maximum flow rate:9 GPM
- wattage:160 KW
- voltage:120 Volts
- heat output:N/A
9.0

Excellent

Our Rating

9.9
Temperature control

9.5
Easy installation
7

HYDRO MASTER
HYDRO MASTER Tankless Water Heater Service Valve Kit with Pressure Relief Valve 3/4-Inch IPS Isolator Clean Brass
Main highlights

Key Features and Benefits
Lead-free brass, 3/4-Inch IPS, easy identification colored handles, includes pressure relief valve, CSA certified, easy installation.

Ideal Use Cases
Perfect for tankless water heater installations requiring safe, lead-free components and effective system isolation for maintenance.

Customer Reviews Summary
Highly praised for its straightforward installation process and the reliable, easy-to-use color-coded valve handles.
8.9

Very Good

Our Rating

9.1
Easy installation

8.9
Simple to use

8.4
worth the money
8

Rinnai
Rinnai REP199iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater with Built-In Recirculation Pump, Up to 7.9 GPM, Indoor Installation, 199,000 BTU
Main highlights

Smart-Circ Energy Efficiency
The Smart-Circ Intelligent Recirculation technology learns your water use patterns and schedules pump and recirculation for optimal energy efficiency and convenience.

Compact Yet Powerful
Ideal for homes needing a compact solution, this tankless gas water heater can provide up to 7.6 GPM, supporting 6 fixtures simultaneously.

Easy DIY Installation
Customers frequently praise the ease of self-installation, especially for those replacing an older unit, with recommendations to follow the installation manual closely.
Key specs
- heat output:199000 BTU
- maximum flow rate:7.9 GPM
- wattage:19000 watts
- product dimensions:14.05W x 27.24H
- style:REP199iN Natural Gas
8.8

Very Good

Our Rating

9.3
Thermal power

9.1
Easy installation

9.1
Efficient Energy Use

8 Best rinnai tankless water heaters of 2025

1

Rinnai RU199iN Condensing Tankless Hot Water Heater, 11 GPM, Natural Gas, Indoor Installation

9.5

9.1

9.1

How do we rank?

How do we rank?

Analyzing top stores

2

NEW Rinnai CX199iN High Efficiency Plus Natural Gas Interior Tankless Water Heater, Up to 11 GPM

3

NEW Rinnai RX199iN Condensing Smart Sense Natural Gas or Propane Tankless Water Heater, Indoor or Outdoor Water Heater, Up to 11.1 GPM, 199,000 BTU

8.0

8.0

4

Rinnai RE180iN Non-Condensing Natural Gas Tankless Water Heater, Up to 8.5 GPM, Indoor Installation, 180,000 BTU

5

Rinnai RUCS65IN Tankless Hot Water Heater, 6.5 GPM, Natural Gas, Indoor Installation

9.3

8.7

8.0

6

Rinnai RSC160iN Smart-Circ Condensing Gas Tankless Water Heater, Super High Efficiency Plus Natural Gas Water Heater, Up to 9 GPM, Indoor Installation, 160,000 BTU

9.9

9.5

7

HYDRO MASTER Tankless Water Heater Service Valve Kit with Pressure Relief Valve 3/4-Inch IPS Isolator Clean Brass

9.1

8.9

8.4

8

Rinnai REP199iN Smart-Circ Non-Condensing Natural Gas Tankless Water Heater with Built-In Recirculation Pump, Up to 7.9 GPM, Indoor Installation, 199,000 BTU

9.3

9.1

9.1

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