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Spec Sheet   Install Manual


Super High Efficiency 7.5 GPM 160,000 BTU Natural Gas Interior Tankless Water Heater
Enjoy an endless supply of hot water with the RUCS75iN, our Super-High Efficiency condensing natural gas tankless water heater from Rinnail. Only the size of a small suitcase, the RUCS75iN is compact, easy-to-install and perfect for indoor locations
    • ENERGY STAR® Qualified - Energy Factor up to .93
      • The RUCS75i, with a maximum of 160,000 BTU, can deliver 7.5 GPM of continuous hot water
        • Built-in status monitor; easily upgradable to MC-91-2 controller for remote operation
          • Temperature Range of 120°F - 140°F, with four convenient pre-set temperatures
            • Stylish white cabinet and matching cover panel
              • Quiet Operation: RUCS75 @ 55dB
                • High Altitude Approved up to 5,400 feet
                  • Ultra Low NOx Compliant
                    • Built-in freeze protection down to -22°F for indoor models and -4°F for outdoor models (gas/electricity required)
                      • Mobile Home Certified
                        • Fuel conversion kits available

                        Isolation valves sold seperately



                        The Rinnai RUCS75iN requires isolation valves during installation.
                        This valve kit includes hot and cold water shut-off valves, hot and cold water drain valves, and an ANSI approved pressure relief valve. Use of these valves will allow flushing of the heat exchanger and aid in servicing and troubleshooting of your Rinnai. You can purchase them with your water heater above or separately.


                        Specifications

                        Dimensions Width: 18.5 inches (469.9 mm)
                        Height: 26 inches (660.4 mm)
                        Depth: 10 inches (254 mm)
                        Weight 57.3 lbs (26 kg)
                        Installation Type Indoor
                        Minimum/Maximum BTU 10,300 / 160,000 Natural Gas
                        Energy Factor 0.93 for Natural Gas
                        Temperature Range Residential Only: 120°F - 140°F (49°C - 60°C)
                        Minimum Activation Rate 0.4 gpm (1.5 lpm)
                        Flow Rate (70° / 50° Temperature Rise) 4.2 / 5.9 gpm (15.9 / 22.3
                        lpm)
                        Hot Water Flow Rate Range 0.26 - 7.5 gpm (0.98 - 28.4 lpm)
                        Controllers Standard: Status Monitor
                        Optional: MC-91-2US
                        Ultra Low NOx Yes
                        Warranty (Residential)* Limited 12-year on heat exchanger, 5-year on parts, 1-year on labor
                        Warranty (Commercial)* Residential Only
                        Mobile Home Certified Yes
                        Valves Shipped in Box No
                        High Altitude Approved Up to 5,400 ft. (1,646 m)
                        Certifications AHRI, CSA, Energy Star®
                        Venting Options Concentric or PVC / CPVC
                        Tankless Rack System (TRS/TRW) Compatible No
                        1/2" Gas Line Compatible*** Yes


                        * It is recommended that a trained and qualified professional who has attended a Rinnai training class complete the installation. The warranty may be voided due to any improper installation.

                        — Installation and service must be performed by a licensed professional.

                         

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                        Installation Type Indoor
                        Minimum/Maximum BTU 10,300 / 160,000 Natural Gas
                        Energy Factor 0.93 for Natural Gas
                        Temperature Range Residential Only: 120°F - 140°F (49°C - 60°C)
                        Minimum Activation Rate 0.4 gpm (1.5 lpm)
                        Flow Rate (70° / 50° Temperature Rise) 4.2 / 5.9 gpm (15.9 / 22.3
                        lpm)
                        Hot Water Flow Rate Range 0.26 - 7.5 gpm (0.98 - 28.4 lpm)
                        Controllers Standard: Status Monitor
                        Optional: MC-91-2US
                        Ultra Low NOx Yes
                        Warranty (Residential)* Limited 12-year on heat exchanger, 5-year on parts, 1-year on labor
                        Warranty (Commercial)* Residential Only
                        Mobile Home Certified Yes
                        Valves Shipped in Box No
                        High Altitude Approved Up to 5,400 ft. (1,646 m)
                        Certifications AHRI, CSA, Energy Star®
                        Venting Options Concentric or PVC / CPVC
                        Tankless Rack System (TRS/TRW) Compatible No
                        1/2" Gas Line Compatible*** Yes

                        Width: 18.5 inches (469.9 mm)
                        Height: 26 inches (660.4 mm)
                        Depth: 10 inches (254 mm)
                        Weight 57.3 lbs (26 kg)

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