Tempstar F97CMN Installation, Start-Up, Operating And Service And Maintenance Instructions page 38

F97CMN and G97CMN: Installation, Start-up, Operating and Service and Maintenance Instructions
Ventilated Combustion
Air intake pipe
Pipe hangar
Ventilated Combustion Air
intake termination in crawl
space
Fig. 45 – Vent Terminations for Ventilated Combustion Air
Size the Vent and Combustion Air Pipes
Furnace combustion air and vent pipe connections are sized for 2-in. (50
mm ND) PVC/ABS DWV pipe. The combustion air and vent pipe
connections also accommodate 60 mm polypropylene venting systems
with outside diameters of approximately 60 mm (2-3/8 inches). Any pipe
diameter change should be made outside furnace casing in vertical pipe.
Any change in diameter to the pipe must be made as close to the furnace
as reasonably possible, see Fig.
The Maximum Vent Length for the vent and combustion air pipe (when
used) is determined from the Maximum Equivalent Vent Length in
Table 11 minus the number of fittings multiplied by the deduction for
each type of fitting used from Table
NOT IN
HORIZONTAL
SECTION
Fig. 46 – Combustion Air and Vent Pipe Diameter Transition
Location and Elbow Configuration
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
3" (76 mm)
12" (305 mm)
CRAWL SPACE
highest level of insulation
ATTIC
45.
8.
FURNACE
PIPE DIAMETER
TRANSITION IN
VERTICAL SECTION
A10497
OPTIONAL
BRACKET
COUPLING
Fig. 47 – Alberta and Saskatchewan Vent Termination
A93034
OPTIONAL CONFIGURATION FOR COMBUSTION
AIR INLET PIPE
In applications where there is a risk of excessive moisture entering the
combustion air inlet pipe, a moisture trap may be added to the inlet pipe
to help prevent moisture from entering the furnace from the combustion
air inlet pipe, see Fig.
When sizing venting systems, the equivalent length of the optional
moisture trap (15 feet/5 M) must be taken into account.
Recommended Combustion Air Inlet Moisture Trap
To prevent moisture from trickling into the furnace vestibule, a trap can
be installed in the intake air pipe near the furnace. To prevent moisture,
38
OPTIONAL TERMINATION
BRACKET FOR 2-PIPE
TERMINATIONS
12 IN. (305 MM) MIN.
SEPARATION BETWEEN
BOTTOM OF COMBUSTION
AIR AND BOTTOM OF VENT.
12-IN. (305 MM)
ABOVE ANTICIPATED
SNOW LEVEL
12 IN. (305 MM) MIN. SEPARATION
BETWEEN BOTTOM OF
COMBUSTION AIR AND
BOTTOM OF VENT.
MAINTAIN 12 IN. (305 MM)
CLEARANCE ABOVE
HIGHEST ANTICIPATED
SNOW LEVEL OR GRADE,
WHICHEVER IS GREATER.
COMBUSTION-AIR
(ELBOW PARALLEL TO WALL)
OVE RHANG
EX HAUST
CLEARANCE TO OVERHANG PER CODE
12 IN. (305 MM) MIN. GROUN D
LEVEL O R ANTICIP A TED SN O W LEVE L
NOTICE
!
47.
A13078A