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Rooftop Unit Comparison Calculator
Welcome to the Rooftop Unit Comparison Calculator. The RTUCC simulates the energy usage of both a high efficiency and a standard efficiency air conditioner. It then compares their energy and economic performance.

The RTUCC displays best in Mozilla Firefox. Good second choices for a web browser are Internet Explorer, Microsoft Edge, and Google Chrome.

To run the RTUCC, characterize the two systems and their environment using the features on this page. Then click the "Submit" button. Use your browser "back" button to return from the Results page to the Controls page or click on the "Return to Controls Page" link. Use the "Restore" button to change all features back to their defaults (more on defaults).

Move your cursor over a question mark near a features's name to display a help tip. Click on the question mark for more detailed information (more on help).

The quick start introduces the RTUCC. The engineering methods describe the calculation engine. Visit the resources page for the user manual and other training materials. Click the version link (below) to view the revision history.
Advanced Features Hidden
Show bin calculations Hide bin calcs
Building Type Office-Medium
State / City MO Kansas City
Schedule M-Fri, 7a.m. to 7p.m.
Indoor Temperature oF     Setback oF 75 oF 5 oF
Total Capacity kBtuh 84 kBtuh
Oversizing Factor % 0%
Candidate Unit EER  @  k$   $/yr 12 EER $4,500 $0
Enable Economizer Economizer enabled
Standard Unit EER  @  k$   $/yr 9 EER $4,000 $0
Enable Economizer Economizer enabled
Electric Utility Rate $/kWhrs 0.08 $/kWhrs
Equipment Life years 15 years
Number of Units units 1 unit
Version 4.3 Chart discounted costs            Discount Rate % Discounted 7.0 %