Allied 95G1UH040BE12X, Запасные части

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507762-01 Issue 1907 Page 23 of 46
Table 7.
Maximum Allowable Exhaust Vent Pipe Length (in ft.) without Insulation in Unconditioned Space for Winter Design
Temperatures
Winter Design Temperatures
1
ºF
(ºC)
Vent Pipe
Diameter
Unit Input Size
040 060 080 100
32 to 21
(0 to -6)
PVC
2
PP PVC
2
PP PVC
2
PP PVC
2
PP
2 in. 18 16 31 28 50 48 30 30
3 in. 9 9 18 18 35 35 47 47
20 to 1
(-7 to -17)
2 in. 9 8 18 16 32 29 30 30
3 in. N/A N/A 8 8 19 19 26 26
0 to -20
(-18 to -29)
2 in. 5 N/A 12 10 22 19 30 27
3 in. N/A N/A N/A N/A 10 10 16 16
1
Refer to 99% Minimum Design Temperature table provided in the current edition of the ASHRAE Fundamentals Handbook.
2
Poly-Propylene vent pipe (PP) by Duravent and Centrotherm
NOTE - Concentric terminations are the equivalent of 5’ and should be considered when measuring pipe length.
NOTE - Maximum uninsulated vent lengths listed may include the termination (vent pipe exterior to the structure ) and cannot exceed
5 linear feet or the maximum allowable intake or exhaust vent length listed in Table 5 or Table 6, whichever is less.
NOTE
- If insulation is required in an unconditioned space, it must be located on the pipe closest to the furnace. See Figure 32.
In both Non-Direct Vent and Direct Vent applications, the
vent termination is limited by local building codes. In the
absence of local codes, refer to the current National Fuel
Gas Code ANSI Z223-1/NFPA 54 in U.S.A., and current
CSA-B149 Natural Gas and Propane Installation Codes in
Canada for details.
Position termination according to location given in Figure
33 or Figure 43. In addition, position termination so it is
free from any obstructions and 12” above the average
snow accumulation.
Conditioned
Space
Unconditioned
Space
Exhaust
Pipe
Intake
Pipe
Conditioned
Space
Pipe Insulation
Figure 32. Insulating Exhaust Pipe in an
Unconditioned Space
At vent termination, care must be taken to maintain
protective coatings over building materials (prolonged
exposure to exhaust condensate can destroy protective
coatings). It is recommended that the exhaust outlet not be
located within 6 feet (1.8m) of an outdoor AC unit because
the condensate can damage the painted coating.
NOTE: See Table 7 for maximum allowed exhaust pipe
length without insulation in unconditioned space during
winter design temperatures below 32°F (0°C). If required
exhaust pipe should be insulated with 1/2” (13mm)
Armaflex or equivalent. In extreme cold climate areas,
3/4” (19mm) Armaflex or equivalent may be necessary.
Insulation must be protected from deterioration. Armaflex
with UV protection is permissable. Basements or other
enclosed areas that are not exposed to the outdoor
ambient temperature and are above 32 degrees F (0°C)
are to be considered conditioned spaces.
Do not use screens or perforated metal in exhaust
terminations. Doing so will cause freeze-ups and may
block the terminations.
IMPORTANT
For Canadian Installations Only:
In accordance to CSA International B149 installation
codes, the minimum allowed distance between the
combustion air intake inlet and the exhaust outlet
of other appliances shall not be less than 12 inches
(305mm).
IMPORTANT