Navien NHB-055 Installation & Operation Manual page 53

System Application #3- Cascade System with DHW Indirect Tank (for High DHW Demand)
Slave1
Slave2
In this configuration, the full capacity of all boilers will be prioritized to the DHW demand.
Note
The aquastat on the DHW indirect tank must be connected to the master unit.
Connect the DHW pump to the master unit.
System Application #4- Cascade System with DHW Indirect Tank (for High DHW Demand)
Slave2 Slave1
In this configuration, the full capacity of all boilers will be prioritized to the DHW demand.
Note
The aquastat on the DHW indirect tank must be connected to the master unit.
Connect the DHW pump to the master unit.
Master
Temperature
sensors (required)
Master
Cold water
Back flow preventor
Expansion tank
Air separator
Cold water
Back flow preventor
Expansion tank
12" (30 cm)
maximum
Return
DHW
Cold water
Temperature
sensors (required)
Hydro/Air separator
Supply
DHW
Indirect tank
Aquastat
Cold water
Supply
Return
Indirect tank
Aquastat
Dirt collector
Installing a Cascade System 53