Rinnai Demand Duo is the combination of between 1 and 6 gas continuous flow water heaters with a storage cylinder.

The storage cylinder allows a short period of high hot water flow rate, greater than the continuous flow rate of the HD water heater(s).

How does it work?

Demand Duo is a complete packaged storage hot water system made up of one or more HD water heaters with a manifold system, primary pump(s), thermostat and a stainless steel storage tank.

The thermostat senses the temperature of the water in the tank, and when it drops below the set point, the primary pump is activated. This flow in turn starts the Rinnai continuous flow HD water heater which returns heated water to the tank.


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