UTICA BOILERS MAH-100 Manual page 29

12" (305 mm) Min. horizontal separation

between combustion air intake and vent of
same appliance.
 12" (305 mm) Min. 84" (2.2 m) Max. vertical
separation between combustion air intake and
vent of different appliances.
 15" (381 mm) Max. horizontal length of vent.
Roof
 Min. vent/intake between different appliances
Terminations 12" (305 mm).
 Max. allowable total vertical vent length with
outside exposure is 10 ft.(3.05 m).
 Abandoned unused masonry chimney may be
used as chase-way for combustion air and
vent. Both combustion air and vent pipe must
exit above top of chimney with clearances as
shown in Figure 5-14.
FIGURE 5-12 - Twin Pipe on Roof Combustion Air On
Sidewall CAN BE USED ON ALL SIZES
Vent Terminal
Combustion Air
Ground
Level
FIGURE 5-13 - Twin Pipe Flue On Sidewall,
Combustion Air On Roof CAN BE USED ON ALL SIZES
Combustion Air
Vent - T Terminal
12" (305 mm)
Anticipated Snow Line
5 - COMBUSTION AIR AND VENT PIPING
FIGURE 5-14 - (2"/ 60 mm & 3" / 80 mm) Twin Pipe
Roof Vent CAN BE USED ON ALL SIZES
This Termination
12" (305 mm) Min.
can be used on:
2" / 60 mm ON
165/205
3" / 80 mm
ON ALL SIZES
vent only
Vent
12" (305 mm) US,
18" (458 mm) Canada Min.
Above
Anticipated Snow Line
FIGURE 5-15 - (3" / 80 mm ONLY) Single Wall
Exhaust Kit and Air Intake Minimum Distance Center
to Center
This Termination
can be used on:
3" / 80 mm
ALL SIZES
vent pipe only
See Grade,
Snow & Ice
FIGURE 5-16 - Horizontal Twin Pipe, Exhaust and
Intake
This Termination
can be used on:
2" / 60 mm ON
Minimum Separation
165/205
3" / 80 mm
ON ALL SIZES
vent only
See Grade,
Snow & Ice
25
15"
(381 mm)
Max.
Roof Line
Combustion
Air
43/4"
[120 mm]
12" (305 mm)
Manufacturer
Recommends
Greater Separation
240013354 REV B [09/15/2021]