Rinnai RUC98iP Ultra Series Indoor Propane Tankless Water Heater


Weight: 64.70 lbs

Rush Order:

Get more venting options out of the box.

The Rinnai Ultra Series line delivers technological leadership and innovation in condensing tankless water heating design. It provides homeowners with an endless hot water, environmental benefits, energy savings, a space saving design. It offers easy installation now with even more venting options out of the box. Rinnai, being the only manufacturer to offer both twin-pipe and concentric PVC venting, no adaptor is required to for both venting options with any installation. One unit, two venting options. In one project to the next, the RUC line of Ultra Series Water Heaters gives you the freedom, right out of the box.


• Earth-friendly technology produces creates less CO2 emissions which contribute to a healthier environment and cleaner air.
• Delivers a continuous supply of hot water wherever and whenever it's needed - simultaneously to multiple faucets and showers.
• Rinnai is the only manufacturer that offers both PVC and Concentric venting, for more flexibility out of the box saving you money, time with the best flexibility to finish the job quickly.
• Small as a carry-on suitcase, its space-saving design allows installation almost anywhere.
• Includes FREE hot and cold water Isolation Valve Kit



​Width: 18.5 inches, Height: 26 inches, Depth: 10 inches


61.7 lbs / 28.0 kg

Installation Type Indoor
Minimum/Maximum Gas Range

15,200 - 199,000 Natural Gas and Propane

Energy Factor 0.95
Temperature Range Residential: 98°F - 140°F with MC-91-2US
Commercial: 98° F - 185° F with MCC-91-2US
Approved Gas Types Propane
Minimum Activation Rate 0.4 GPM
Flow Rate vs. Temperature Rise

70°F at 5.5 GPM. 50°F at 7.7 GPM

Hot Water Flow Rate Range

​0.26 - 9.8 GPM

Controllers MC-91-2US (included)
MCC-91-2US (optional for Commercial or Hydronic Applications)
MC-100V-1US Deluxe Controller (optional)
BC-100V-1US Bathroom Controller (optional)
Ultra Low NOx ​Yes
Warranty (Residential) Limited 12 years on heat exchanger, 5 years on parts, 1 year on labor (5 year optional on labor)
Warranty (Commercial) Limited 5 years on heat exchanger, 5 years on parts, 1 year on labor (5 year optional on labor)
Circ-Logic Compatible


Circ-Logic Compatible (P/N) ​REU-KB3237FFUD-US
Mobile Home Certified ​Yes
High Altitude Approved Up to 10,200 ft.
Certifications ​​AHRI, UPC, CSA, NSF, UMC, Energy Star®
Venting Options ​PVC/CONCENTRIC PP


Comprehensive brochure
Ultra series brochure
Installation & operation manual

Frequently Asked Question ("FAQ")

Q1: What is the difference between this model, the RUc98iP and the older RU98iP?
A1: There is only one difference. With the RUc98iP, Rinnai added a PVC adapter at the vent opening. Otherwise the units are identical.

Q2: What is the difference between this model, the RUC98iP and the newer RU199iP?
A2: The RU199iP has several improvements, mainly:
* It has more modular components, making the unit easier to service and repair.
* The heat exchanger is stainless steel versus copper on the RUC98iP.
* It has a zero governor gas valve which allows it to work with lower pressure in the gas pipe.
* It has more venting options. It can use 2" PVC venting or concentric. RUC98iP required 3" or 4" PVC or concentric.
* The included LP to NG conversion kit is easier to change.
* The warranty is 15 years versus 12 years on the RUC98iP.

Q3: What is the difference between the RU, RUR and RUC series?
A3: Rinnai's RU series heaters such as the RU80e and RU90e are simply the outdoor versions of the RUC units.

The RUR series heaters such as the RUR98i and the RUR98e have a built-in recirculation pump. The RUC series heaters such as the RUC98i and the RUC80i do not have the recirc pump.

All of these heaters are condensing.

Rinnai® is a registered trademark of Rinnai Corporation. GadgetsGo is not associated with or sponsored by Rinnai Corporation.

Related Gadgets

Rinnai 169044 Pipe Clamp
Quick View
$7.00 $5.95

Min Order: 5

Average Customer Rating:

1 most useful customer reviews
Alberto Santana
Feb 23, 2018
This customer purchased this item.
Great unit that replaced to tan water heaters and serves 3.5 bathrooms in my home. Purchasing from GadgetsGo was a pleasure.
Loading...Was this review useful to you? Yes (0) / No (0)

Type the characters you see in the picture...

The code is case-sensitive and must be entered exactly as above.

Share Rinnai RUC98iP Ultra Series Indoor Propane Tankless Water Heater