Rinnai SE Series 18" 160K BTU 7.5 GPM Gas Tankless Water Heater

Rinnai SE Series 18" 160K BTU 7.5 GPM Gas Tankless Water Heater

Regular price $1,893.00
Regular price Sale price $1,893.00
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Rinnai has been delivering nothing but the best for almost 100 years and that award-winning dedication can't help but be noticed in its SE Series. The RUCS75 and all of the SE Series models offer Rinnai's incredibly efficient condensing design line of tankless heaters. Rinnai's SE Series models utilize two premium heat exchangers to provide optimal reliability and durability. With a 0.90 Uniform Energy Factor and a sleek, innovative design. 

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 RUCS75 at 160,000 BTUs, available in natural gas and propane, offers condensing technology with lower 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.

These new Rinnai RUCS 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.

Compact Design Saves Space

  • The RUCS75 is designed to be able to be installed on any wall or in any compact space, including non-traditional places like an attic or crawlspace that hides your unit and frees up valuable space in your home.

Energy-Efficient Promise That Saves You Money

  • Tankless water heaters avoid the need to keep a large amount of reserve water heated at all times. This saves resources by only heating water when you need it, while an electric ignition avoids the constantly wasted energy of a standing pilot light.

Continuous Water for Multiple Applications

  • You should be able to have two people shower at once or do the laundry while the dishwasher is running. Rinnai tankless water heaters provide an endless supply of hot water that remains uninterrupted, even when you're the last one in line for the shower.

What's Included

  • Tankless Water Heater
  • MC-91-2 temperature controller (Integrated into indoor models)


  • Energy Efficient: ENERGY STAR product with an Energy Factor of .93 and Uniform Energy Factor of .90
  • Provides a reliable source of hot water to multiple fixtures simultaneously in any size home
  • Only uses energy when hot water is needed
  • An excellent choice for smaller spaces. Fits in crawl spaces and attics without compromising output
  • Easy installation with PVC/CPVC in conjunction with the Ubbink Concentric to Twin Pipe adaptor (other venting options available)
  • Automatic frost protection
  • Compatible with Wi-Fi devices


Manufacturer Trade Model Number RUCS75iN, RUCS75iP, RUS75eN, RUS75eP
Product Depth 10.1 in / (257 mm)
Product Height 31.1 in / (789.6 mm)
Product Width 18.5 in / (470 mm)
Product Weight 57.3 lb / (26 kg)
Gas Type Natural Gas/Propane
Installation Type Indoor/Outdoor
Recirculation Capable Yes
Residential Energy Star Yes
Uniform Energy Factor 0.9
Energy Factor 0.93
Domestic Hot Water Flow Rate (Maximum) 7.5 GPM / (28.4 l/min)
Wi-Fi Capable Yes
SCAQMD Approved Ultra-Low NOx


To connect with a Rinnai-trained installer, you can utilize the Rinnai Dealer Locator by visiting the link: Alternatively, you can directly reach out to Rinnai's dedicated customer support team via the Toll-Free Number: 1 (800) 621-9419.

Options and Accessories

3" Control-R Wi-Fi Module for Tankless Water Heaters

  • Works with all Rinnai Tankless Water Heater models manufactured 2006 and newer (except RH180 Hybrid Tank-Tankless WaterHeaters).
  • The Lime Condition (LC) notification will not appear in the Rinnai
  • App, when the Control-R™ Wi-Fi Module is paired with the following series of Rinnai Tankless Water Heaters, manufactured prior to 2009: VA, VB, KA, and V53e

3/4” Feed ScaleCutter System

  • Keeping scale-causing minerals in solution inhibiting limescale formation
  • Changes the shape of the precipitated lime scale preventing the accumulation
  • Coats wetted surfaces with a micro-thin layer that provides corrosion control

Condensate Neutralizer Kit

  • The Rinnai Condensate Neutralizer Kit is an accessory for your Rinnai Tankless Water Heater System.
  • For Rinnai condensing products

 Documents & Files


12 yrs on Heat Exchanger
5 Year Warranty on Parts

1 Year Labor Warranty


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