Measuring Flue Length - Navien NCB300-28K Installation & Operation Manual

6.2.2 Vertical Coaxial Removal (Type C
Standard Removal System
Ø60/100 => Max. length: A = 8 m
Ø80/125 => Max. length: A = 28 m
Extended Removal System
B
Ø60/100 => Max. length: A+B-(1 x 45°elbow) = 8-1 = 7 m
Ø80/125 => Max. length: A+B-(1 x 45°elbow) = 28-1 = 27 m
Pipe Diameter Maximum
(mm) Length (m)
Ø60/100
Ø80/125 28
40 Flue System
)
33
A
A
A
Minimum 350 mm
Equivalent
Elbow
Length (m)
8
45°

6.3 Measuring Flue Length

The gas removal and air intake systems may be oriented in any
direction (north, south, east or west). Some special components
such as elbows are used to help reach certain positions. Each
removal terminal kit includes an adapter for connection to the
boiler and a removal terminal.
The total length of the flue must not exceed the maximum value
defined. If the flue installation includes elbows while calculating
the total length you must take into account that each elbow has
a resistance equal to a specific linear Leq equivalent length (see
table).
There are two different types of terminals (horizontal and
vertical), for the coaxial flue system.
Carefully study the diagrams representing the different types of
removal and select the one that best suits the conditions of your
installation. To choose the removal accessories required for each
installation, see the list of accessories on the NAVIEN price list.
Maximum Total Length
Type
Coaxial
Equivalent Length of Elbows and Adapters
Type
Coaxial
1.0
Pipe Diameter
Orientation
(mm)
Horizontal
Ø60/100
Vertical
Horizontal
Ø80/125
Vertical
Pipe Diameter
Elbow
(mm)
Adapter
Ø60/100 -> -
Ø80/125
45°
Ø60/100
90°
45°
Ø80/125
90°
Maximum
Length (m)
8
8
27
28
Equivalent
Length (m)
0.5
1.0
1.5
1.0
2.2