RED Calc Free

v1.0, Legacy Tool

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You can use RED Calc Pro for 30 days free!

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Summary: This “solve-all” tool is used for sizing an instantaneous (tankless) hot water heater. It can also be used to determine the maximum hot water flow rate for a given system and temperature rise. See Tool Guide. Click on any input or result label for help. By using this tool (application) you agree to the Terms of Use.

This legacy tool is NOT optimized for mobile devices. Stay tuned for the mobile-optimized version 2.0.