Welcome to the Rinnai Commercial
Tankless Sizing Calculator.

Leveraging decades of global commercial water heating experience, Rinnai Tankless Water Heaters deliver performance and reliability. Precision engineering allows Rinnai Tankless Water Heaters to produce an endless supply of hot water to suit even the most demanding applications — from restaurants to hotels to multifamily residences to schools and more — conserving energy that can save thousands of dollars in capital, operational and life cycle costs, while providing redundancy and saving space.

Find out what which models are right for your application.

Let's get started...

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1 Select Application

Tankless Only
Tankless with Storage
Both
Condensing Tankless Water Heaters
Non-Condensing Tankless Water Heaters
Both

2 Enter Application Information

Unit Constraints

Sizing Constraints

°F
°F
°F
ft
FIXTURES QTY Diversity

3 Select One of the Following Recommendations:

Model RU28e Selected

Required Accessories and Controls for the
ITEM PART NUMBER QTY
Sizing Recommendation (Tankless w/Storage)
QTY MIN TANK SIZE PUMP SIZE
Related Documents for

4 Summary:

Application:

Zip / Postal Code:
Show recommendation for:
Show me:

Unit Contraints

Unit of Measure:
Fuel Type:
Location:

Sizing Contraints

Supply Temperature: °F
Ground Temp: °F
Temperature Rise: °F
Elevation: ft
FIXTURES QTY WSFU Diversity TOTAL WSFU GPH TOTAL GPH

5 Download Your Sizing Report

Please have an engineer contact me

Download Your Sizing Report

You can now view or download your calculation results and recommendations below:

Sizing Report

Authorized Service Provider

An ASP is a factory authorized service provider for Rinnai products both during and after the product warranty period. They are committed to providing prompt, courteous and professional service in the event you experience a problem.

Customer Reviews

This percentage is based on a satisfaction survey completed by customers after the installation of a Rinnai product.

Zipcode

This is the zipcode you want to use as the center of your dealers search.

If not set our website will do its best to try to determine based on our best guess of your current position.