Navien NaviCirc Installation And Operation Manual page 30

9. Put the water heater cover back on and secure it with the
4 screws.
You can configure it as either Type 1 or Type 2 if you install an
external recirculation line.
G H C
Condensate
Domestic
Gas
Hot Water
Domestic Cold Water
Domestic Recirculation
Return
[Type 1. Recirculation using External Pump -
Return line ties into Cold Water Inlet
(NPE-S2 Models)]
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