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74 Installing a Cascade System
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System Application #3- Cascade System with DHW Indirect Tank (for High DHW Demand)
System
pump
12” (30 cm)
maximum
Sub2
Sub1
Main
Temperature
sensors (required)
Cold water
Supply
Return
Backflow preventer
Expansion tank
Cold water
DHW
Indirect
tank
Aquastat
Air separator
Note
●
In this configuration, the full capacity of all boilers will be prioritized to the DHW demand.
●
The aquastat on the DHW indirect tank must be connected to the main unit.
●
Connect the DHW pump to the main unit.
●
Connect the system pump to the units (main or sub).
●
System Application #4- Cascade System with DHW Indirect Tank (for High DHW Demand)
Sub2
Sub1
Main
Cold water
Supply
Indirect
tank
Aquastat
System
pump
Cold water
DHW
Return
Dirt collector
Hydro/Air separator
Backflow preventer
Expansion tank
Temperature
sensors (required)
Note
●
In this configuration, the full capacity of all boilers will be prioritized to the DHW demand.
●
The aquastat on the DHW indirect tank must be connected to the main unit.
●
Connect the DHW pump to the main unit.
●
Connect the system pump to the units (main or sub).
Summary of Contents for NFB-175H
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