Navien NaviCirc Installation And Operation Manual page 68

* A Taco 008-BC6 or Grundfos 15-42 BUC7 (or equivalent) circulation pump
is recommended for use with the NCB-H boiler and DHW recirculation
systems.
* When using the external recirculation mode, observe the following
maximum recirculation pipe lengths including fittings (
recommended). Lengths in excess of these limits will require a larger
recirculation pump.
Pipe Diameter
Maximum Pipe Length
To use HotButton mode, install a HotButton and
Note
●
recirculation pump.
Install the NaviCirc recirculation valve to the faucet
●
furthest from the NCB-H boiler.
If installed in close proximity to the boiler, faucets
●
further down the supply line will take longer to
receive hot water.
Maximum Pipe Lengths
1
100 ft (30 m)
68
/ "
2
3
/ " pipe is
4
3 / "
4
400 ft (120 m)