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Rinnai Ultra Series Tankless Water Heaters deliver innovation and technological leadership in condensing tankless water heating design, while providing homeowners with an endless supply of hot water, energy savings, a space-saving design and environmental benefits. The NEW RUCS75i at 160,000 BTUs, available in natural gas and propane, offer condensing technology with lower to mid-range capacity at attractive price points. As the only manufacturer to offer both concentric and PVC/CPVC dual pipe venting options on the same unit, the RUCS models join the Ultra Series lineup of innovative designs and enduring values.

  • 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 separately
  • Min. BTU Input - 10,300
  • Max. BTU Input - 160,000
  • Warranty (Residential) - Limited 12-year on heat exchanger, 5-year on parts, 1-year on labor

These new Rinnai RUCS/RUS Condensing Tankless Water Heaters expand Rinnai’s Ultra Series condensing lineup to 6 models, in both indoor and outdoor versions, ranging from 130,000 to 199,000 BTU with efficiencies from .93 EF to .96 EF, providing the most complete condensing lineup in the industry.

Need this water heater installed? Rinnai can help! Simply call 844.348.4715.
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Product Type:
Tankless Heater
Installation Type:
Indoor Only
Fuel Type:
Natural Gas
Energy Star Rated:
Energy Factor:
BTU Input:
Temperature Range (F):
120°F to 140°F
Flow Range (GPM):
0.26 - 7.5
Cold Water Inlet (NPTM):
Hot Water Outlet (NPTF):
Gas Connection:
Height (Inches):
Width (Inches):
Depth (Inches):
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