The Rinnai RU180 is part of the Sensei SE+ Series, a line of super high efficiency, Energy Star Qualified, tankless hot water heaters. The RU180 is for residential and commercial use. The RU180 is available in either Natural Gas or Liquid Propane and must be purchased for indoor or outdoor use*. Indoor versus outdoor installation is not interchangeable and must be decided at time of purchase. Indoor installation of the RU180 offers both concentric and PVC/CPVC venting. The dual venting option on the top of the unit allows for maximum installation flexibility - one concentric vent or two PVC/CPVC/PP pipes can be used for venting. With concentric venting, one pipe allows for fresh outside air in, while the other allows for exhaust to go out. Outdoor installation does not require venting. This item, the RU180i, is for indoor installation and requires venting.
The Rinnai Sensei Series with condensing technology offers built-in freeze protection down to -22°F on the indoor units. The unit features an integrated check valve located between the turbo fan and the combustion chamber to prevent cold air from entering the venting system and backflow of exhaust in common vent applications. The Fiber Mesh Premix Burner helps to provide even flame distribution for optimal performance for any demand.
It features 180,000 BTUs and hot water delivery with a flow rate that ranges from 0.26 - 9.0 GPM. The minimum GPMs is perfect for low demand uses such as shaving, where warm water is needed but not at a high rate! It is the ideal tankless solution for a home with 2-1/2 bathrooms. The RU180 is optimal for simultaneous use of 3 - 5 fixtures at one time. So 2 people can shower and get ready to go out, and still have hot water to run a load of laundry or the dishwasher or both! Simultaneous fixture use is directly linked to the ground water temperature. Please refer to the chart in the photos above.The MC-91-2US controller is included with the water heater as part of the front panel. The default minimum temperature setting is 98° with a maximum of 120°F. The unit offers a maximum setting of 140°F with parameter adjustment. A parameter adjustment on the RU180 unit can be made for greater hot water flow - up to 10 GPM - as well.
In a condensing tankless water heater, such as the RU180, once you turn on the tap, cold water goes into tankless heater and the flame is activated. Water is pre-heated as it passes through the stainless steel heat exchanger then continues to be heated as it passes through the coils in the copper heat exchanger, exits the water heater, into your pipes and up to the fixture calling for the hot water. Depending on the amount of hot water called for, the flame adjusts accordingly to heat more or less water.
Benefits of a Tankless Hot Water Heater:
- Endless hot water - Heats water as it goes through the pipes, offering endless hot water for your home (or business)
- Hot water on demand - Once you turn the water on, hot water runs through your pipes and out the faucet! Virtually no time or water is wasted waiting for the water to heat up
- Highly Efficient - Gallon for gallon, you will spend less money heating your hot water. With a tankless system the water is heated on demand rather than sitting in a storage tank. A storage tank typically heats the water intermittently throughout the day and night not only when it is needed. This unit is Energy Star Qualified and features an Energy Factor of 0.93 (the closer to 1.0 the better)
- Long lasting - Unlike a storage tank in which the water sits in the tank all the time creating sediment and rust, a tankless water heater will last longer
- EZ Connect - Allows for connection of two units together
The RU180 offers WiFi Technology (Control-R WiFi Module sold separately) for remote monitoring, management. (Remote diagnostics and monitoring requires a monitoring dealer.) With WiFi monitoring, only Rinnai Service Providers can monitor the efficiency of your tankless water heater as well as send you automatic maintenance alerts and possibly offer faster service. The Control-R WiFi Module attaches right to your Rinnai tankless water heater. Simply download the mobile app and you can control your hot water from anywhere in the home, as well as activate recirculation (if installed). The Control-R also allows for pairability and voice activation with Amazon Alexa.
The RU180 offers Circ-Logic capabilities. Recirculation allows for the water in the plumbing system to provide hot water more quickly once the tap is opened, using the cold water line for recirculation. The recirculation mode is for use in residential installations only. Additional accessories such as a thermal bypass valve are required unless there is a dedicated return line installed in your home. The RU180 ships with isolation valves for easier maintenance and service.
With a tankless hot water heater, space is rarely an issue. A Rinnai RU180 tankless heater takes up a little more space than a carry-on suitcase - 26.4"h x 18.5"w x 11.5"d. They are designed to be installed on a wall with the following clearances:
(0" from vent components)
|Bottom / Ground:||12"|
(minimum of 24" required for servicing)
The RU180i offers flexible venting options for installation.
- Concentric or Schedule 40 PVC/CPVC
- Direct vent (Concentric and Twin Pipe)
- Non-Direct Vent (Room Air)
- Common Direct Vent (Direct Vent and Room Air)
- Maximum Equivalent Vent Lengths:
- Twin Pipe Vent Sizes and Lengths: 2"/ 65 Ft. or 3"/ 150 Ft.
- Concentric Vent Sizes and Lengths: 2" x 4"/ 65 Ft. or 3"x 5" / 150 Ft.
*Indoor and Outdoor Installation are specific to the model chosen. RU180iP and RU180iN are for indoor installation and require venting while RU180eP and RU180eN are designed for outdoor installation and venting is not required. Both installation types are available in either Liquid Propane (P) or Natural Gas (N). Certified for installation in Manufactured (Mobile) Homes.
To find a local, Rinnai-trained Advanced Comfort Expert that installs Rinnai products in your area click here.
As an added bonus Rinnai has partnered with Folds of Honor. For every Rinnai tankless water heater or boiler that is sold, a contribution is made to Folds of Honor. This provides over 50 scholarships to trade schools for the spouses and children of America's fallen and disabled service members.
- Bay Area AQMD (Reg 9, Rule 6)
- Sacramento Metropolitan AQMD (Rule 411)
- San Joaquin Valley APCD (Rule 4902)
- Santa Barbara County APCD (Rule 352)
- South Coast AQMD (Rule 1146)
- Ventura County AQMD (Rule 74-11)
- Yolo-Solano AQMD (Rule 2.37)
- Fuel Type:
- Liquid Propane (LP) or Natural Gas (NG)
- Installation Type:
- Product Use:
- Residential and Commercial
- Energy Factor (EF):
- Gallons Per Minute (GPM):
- 0.26 - 9.0
- Includes Heat Pump:
- Energy Star:
- Overall Depth (in.):
- Overall Height (in.):
- Overall Width (in.):
- Net Weight (lbs.):
- Water Connection Size:
- 3/4" NPT
- Heat Exchanger Warranty (Residential):
- 15 Year
- Heat Exchanger Warranty (Commercial):
- 8 Year
- Parts Warranty:
- 5 Year
- Labor Warranty:
- 1 Year; 5 Year with Registration within 90 Days
It is recommended that you use a Rinnai Authorized Installer when installing your hot water heater. Your hot water heater includes a
- Limited 15 Year Warranty on Heat Exchanger
- 5 Year Warranty on Parts
- 1 Year Labor Warranty; 5 Year with Registration within 90 Days
- Limited 8 Year Warranty on Heat Exchanger
- 5 Year Warranty on Parts
- 1 Year Labor Warranty
Please note Rinnai is adjusting the language in its warranty terms and conditions currently noted in the User Installation manuals. The revised statement will read as follows: "This Limited Warranty applies only to products that are installed in the United States and Canada. Improper installation may void this Limited Warranty. It is recommended that a trained and qualified professional who has attended a Rinnai installation training class complete your installation."
All warranties will be honored as written above.