Installing A Cascade System; Connecting Water Supplies - Navien NCB-190/060H Installation & Operation Manual

8. Installing a Cascade System

When installing a cascade system, carefully consider the design of the system and the features of the installation
location. Follow all local codes and regulations, as well as all guidelines for installing the combi-boiler and water
heaters. The following sections describe additional considerations that are specific to installing cascade systems.
Read them carefully before designing or installing the system.

8.1 Connecting Water Supplies

Several options are available for applying a cascade system of combi-boilers and water heaters. The options
shown here are only examples. The setup you choose will vary based on the installation location, local building
codes, and other factors. Follow all applicable regulations when installing a cascade system.
You can connect up to 1 combi-boiler and 15 Navien water heaters (NPE-A2 or NPE-S2 model) to meet high-
volume water heating demands. Some possible connection options include the following:
Example of a Basic Cascade System Application
Pressure
Relief Valve
Heating
Supply
Pump
Air Separator
with Expansion
Tank
Optional System
Temperature Sensor
Heating Return
<NPE-A2 Series>
Main
Sub1
NaviClean
(recommended)
[NCB-H]
<NPE-A2 Series>
Sub2
Ball Valve
Faucet
Installing a Cascade System
Ball Valve
Check Valve
75