Selecting A Flue System - Navien NCB-20LHWE Installation & Operation Manual

For vertical ducts, the outlet must be at least 60 cm
Note
from any opening.
The dimensions (B, C, D, and E) may be reduced to
25 mm, as long as the ue terminal is extended to
clear any overhangs.

6.2 Selecting a Flue System

WARNING
The gas removal ducts must not be in contact with
or near ammable materials and they must not pass
through any structures or walls of buildings made of
such materials.
If you replace the boiler, the old gas removal system
must be replaced by a new one.
The standard ue must be installed level. If ue
extensions are needed, they must have a 3 degree fall
back to the appliance.
The fume extraction connection depends on the type of system
chosen (coaxial removal system or dual duct removal system).
Carefully follow the instructions given below:
Coaxial System
For coaxial system, t the components as shown in the gure:
Adapter
Dual Duct System
For dual duct system, t the components as shown in the gure:
1. Remove the air intake cap.
2. Connect the corresponding adapters to the boiler (the gas
removal and air intake adapters).
3. Connect the gas removal and intake ducts.
Exhaustion and intake ducts
Air intake cap
Adapter
Flue System 29