3" /80 Mm Only) Flexible Vent System - UTICA BOILERS MAHF-165 Installation, Operation And Maintenance Manual

5.10 (3" /80 mm Only) Flexible Vent System

Flexible Pipe Minimum & Maximum Vent Lengths
3" [80 mm]
Diameter Pipe
Exhaust
Natalini
Intake
Exhaust
DuraVent
®
Intake
Exhaust
Centrotherm
Intake
Exhaust
Z-Dens
Intake
Single Wall Elbows - Equivalent Length
45° bend
90° bend
NOTICE
Flexible vent systems shall only be run vertical.
Horizontal runs before adapting to flexible must be
rigid pipe.
• Maximum vent lengths based on equivalent straight
runs only. Include rigid pipe and fittings in overall
equivalent length calculations.
• Flexible venting installations use single wall
polypropylene to pass flue gasses to base of chimney,
then flexible venting to get them to termination at the
top.
• Combustion air is not supplied through masonry
chimney. Combustion air must be from outside using 3"
[80 mm] single wall polypropylene.
• Position boiler to use minimum of rigid single wall
polypropylene venting to the chimney.
• Follow venting manufacturer's instructions on assembly
and clearances to maintain.
• Avoid sharp bends in flexible venting.
5 - COMBUSTION AIR AND VENT PIPING
125/150 165/205
Min Max Min
6 ft 6 ft
75 ft
[22.8 m]
[1.8 m] [1.8 m]
6 ft 6 ft
50 ft
[15.2 m]
[1.8 m] [1.8 m]
6 ft 6 ft
82 ft
[24.9 m]
[1.8 m] [1.8 m]
6 ft 6 ft
50 ft
[15.2 m]
[1.8 m] [1.8 m]
6 ft 6 ft
52 ft
[15.8 m]
[1.8 m] [1.8 m]
6 ft 50 ft 6 ft
[1.8 m] [15.2 m] [1.8 m]
6 ft
NA
[1.8 m]
3" [80 mm]
0.82 ft [0.25 m]
1.64 ft [0.50 m]
FIGURE 5-24 - (3" / 80 mm Only) Flexible Venting
System CAN BE USED ON ALL SIZES
Max
50 ft
[15.2 m]
50 ft
[15.2 m]
50 ft
[15.2 m]
50 ft
[15.2 m]
50 ft
[15.2 m]
50 ft
[15.2 m]
50 ft
[15.2 m]
Combustion
Air
24
Vent Terminal
Flexible Vent
Rigid Vent
240012874 REV A, [01/31/2020]