Combustion Air And Vent Pipe - UTICA BOILERS UB90-50 Installation, Operation & Maintenance Manual

Connections And Termination
Provisions for combustion and ventilation air must be
in accordance with section, Air For Combustion and
Ventilation, of the National Fuel Gas Code,ANSI 2223.1/
NFPA54, or National Gas and Propane Installation Code,
CAN/CGA-B 149.1, or applicable provisions of the local
building code.
Boilers require dedicated direct vent system. All air for
combustion is taken directly from outdoors through
combustion air intake pipe. All fl ue products are discharged
to outdoors through vent pipe.
Venting Materials:
1.
WARNING
!
Use of cellular core PVC (ASTM F891), cellular core
CPVC, or Radel® ,(Polyphenolsulfone) in venting
systems could result in death, or serious injury.
WARNING
!
Covering non-metallic vent pipe and fi ttings with
thermal insulation shall be prohibited. Use in venting
system could result in death or serious injury.
Table 4 - Combustion air and vent pipe fi ttings
must conform with the following:
Item Material
PVC schedule 40
PVC - DWV
CPVC schedule 40
SDR-21 & SDR-26 PVC
Vent Pipe
and Fittings
ABS-DWV
Schedule 40ABS
PP (Polypropylene)
Pipe and Components
PVC
Pipe
Cement/ CPVC
Primer
Schedule 40 ABS
• IPEX is approved vent manufacturer in Canada listed
to ULC-S636.
• IPEX System 636 Cements and Primers are approved
in Canada listed to ULC-S636.
Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel
(Polyphenolsulfone) in venting systems shall be prohibited.
NOTICE
Use of PP piping, follow manufacture"s installation
instructions and requirements.

COMBUSTION AIR AND VENT PIPE

Standards
ANSI/ASTM D1785
ANSI/ASTM D2665
ANSI/ASTM D1784/
F441
ANSI/ASTM D2241
NOT APPROVED FOR
CANADA
ANSI/ASTM D2661
ANSI/ASTM F628
UL 1738
ULC S636-08
ANSI/ASTM D2564
ANSI/ASTM F493
ANSI/ASTM D2235
,
®
22
Canadian installations:
2.
• First 3 feet (900mm) of venting must be readily
available for visual inspection.
• Specifi ed primers and glues of certifi ed vent
system must be from single manufacturer, and not
intermixed with other manufacturer's vent system
parts.
• Components of the certifi ed system must not be
interchanged with other vent systems, or unlisted pipe
and/or fi ttings.
NOTICE
Transition from 2" pipe to 3" pipe must be made in
vertical run.
Boiler combustion air and vent piping connections are
3.
sized for 2" pipe. Any pipe size change (to 3") must be
made outside of boiler casing in vertical run of pipe to
allow for proper drainage of vent condensate. Due to
potential for fl ue gas temperatures over 155°F, fi rst fi ve
(5) feet of vent pipe must be CPVC, the remaining vent
pipe can be PVC. If any elbows are employed within the
fi rst 5 feet of vent, they must be CPVC also. Two (2) - 30"
pieces of 2" CPVC pipe. 2½" piece of 2" CPVC pipe, a 2"
CPVC elbow and 2" CPVC pipe coupling are furnished with
the boiler. No requirement when using PP pipe.
Combustion air and vent piping lengths. Table 5,
4.
Page 23 . If vent exceeds 5 ft. fi rst 5 ft. of vent piping
run must be 2" CPVC:
Length of pipe is counted from boiler jacket (air
intake pipe) or from vent pipe connector(vent pipe).
Termination is not counted toward the "Total Equivalent
Length".
For elbows, reduce maximum vent length as shown:
• 2" 90° elbow - 2 ft. per elbow.
• 3" 90° elbow - 3 ft. per elbow.
To add two (2) 90° elbows to a 3" pipe for a 75 boiler.
Each elbow is 3 ft. per 90° elbow for a total of 6 ft.
(1 elbow @ 3 ft. + 1 elbow @ 3 ft. = 6 equivalent ft. of
pipe)
Total additional pipe is then subtracted from maximum
allowable pipe length to give new maximum length of
112-6=106 ft. with two (2), 90° elbows.
"TOTAL EQUIVALENT LENGTH":
Original 112 ft. max. - 6 equivalent ft. for 2 elbows =
new 106 ft. maximum length.
Example: