Best for Quick Replacements
Demand Duo® is great for emergency replacement and high-capacity needs because it has the storage capacity of a tank paired with the energy efficiency and longer life of a tankless.
Demand Duo® Benefits
Flexible Installation
Features a preassembled gas connection with an installed drip leg and swivel flex line allowing for quick and hassle-free installation.
DuoSmart Delivers
Demand Duo® uses DuoSmart Tank Technology™ to deliver more value than standard tanks, including a lower cost of ownership, energy-saving performance, and abundant hot water when you need it.
Optimized Controller
The new digital controller can manage building circulation, eliminating the need for a separate aquastat.
How it Works
Greater Capacity and Lifespan
The Rinnai Demand Duo® pairs a durable 119-gallon tank with a Rinnai CU199 tankless unit.
- A direct replacement with connections similar to most high-efficiency tanks.
- Simple to install and keeps pace with an establishment’s hot water needs.
Demand Duo® Solutions
Demand Duo®
H-Series
Bringing a multitude of installation options as well as an upgraded recovery pump for improved tank recovery time.
- Choice of multiple tankless and tank options
- Preassembled electric and gas connections
- Set building recirculation and temperature setpoint with the Digital Controller
Demand Duo®
R-Series
Our newest line of commercial hybrid water heaters brings the performance, versatility and reliability from Rinnai. And it's backed by the industry's best warranty.
- No new vent runs or structure penetrations required
- Longer lifespan with no thermal stress on tank
- Easily connect to existing 6" B-Vent
Demand Duo® 2V
Combining the redundancy and performance of our tankless rack systems with the hybrid technology of Demand Duo®.
- Built-in redundancy for reliable hot water
- Cutting-edge technology that’s easy to maintain
- ASME certified option available
