Goodman GMV9 Installation Instructions Manual page 17

Direct vent installations require both a combustion air intake and a
vent/flue pipe. The pipes may be run horizontally and exit through
the side of the building or run vertically and exit through the roof of
the building. The pipes may be run through an existing unused
chimney; however, they must extend a minimum of 12 inches above
the top of the chimney. The space between the pipes and the chim-
ney must be closed with a weather tight, corrosion resistant flash-
ing. Both the combustion air intake and a vent/flue pipe termina-
tions must be in the same atmospheric pressure zone. Refer to
Section IX, Vent/Flue and Combustion Air Pipe - Termination Loca-
tions or Concentric Vent Termination for specific details on termina-
tion construction. For details concerning connection of pipes to the
furnace, refer to the Section IX, Vent/Flue Pipe and Combustion
Pipe - Standard Furnace Connections or Alternate Furnace Con-
nections.
V /F C
ENT LUE AND OMBUSTION
Refer to the following table for applicable length, elbows, and pipe
diameter for construction of the vent/flue and combustion air intake
pipe systems of a direct vent (dual pipe) installation. The number of
elbows tabulated represents the number of elbows and/or tees in
each (Vent/Flue & Combustion Air Intake) pipe. Elbows and/or tees
used in the terminations must be included when determining the
number of elbows in the piping systems.
If the combustion air intake pipe is to be installed above a finished
ceiling or other area where dripping of condensate will be objection-
able, insulation of the combustion air pipe may be required. Use
1/2" thick closed cell foam insulation such as Armaflex™ or Insul-
tube™ where required.
Direct Vent (Dual Pipe) Maximum Allow able Length
of Vent/Flue & Combustion Air Intake Pipe (ft)
(4)
Unit Input Termination Pipe
(Btu) Style (inch)
Standard 2
45,000
Alternate 2
2
Standard
3
70,000
2
Alternate
3
Standard 3
90,000
Alternate 3
Standard 3
115,000
Alternate 3
COUNTERFLOW
Direct Vent (Dual Pipe) Maximum Allow able Length
of Vent/Flue & Combustion Air Intake Pipe (ft)
Unit Input Termination Pipe (4)
(Btu) Style (inch)
2
Standard
3
70,000
2
Alternate
3
2
Standard
3
90,000
2
Alternate
3
1) Elbows and/or tees used in terminations must be included when deter-
mining quantity of allowable elbows in the system.
2) Number of elbows tabulated are for each (Vent/Flue & Combustion Air
Intake) pipe.
3) Minimum requirements for each Vent/Flue & Combustion Air Intake pipe
is five (5) feet in length and one elbow/tee.
A P L D
IR IPE ENGTHS AND IAMETERS
UPFLOW
(1)(2)(3)(5)
Number of Elbow s
1 2 3 4 5 6
71 68 65 62 59 56 53
58 55 52 49 46 43 40
49 46 43 40 37 34 31
71 68 65 62 59 56 53
36 33 30 27 24 21 18
57 54 51 48 45 42 39
71 68 65 62 59 56 53
57 54 51 48 45 42 39
49 46 43 40 37 34 31
35 32 29 26 23 20 17
(1)(2)(3)(5)
Number of Elbow s
1 2 3 4 5 6
49 46 43 40 37 34 31
71 68 65 62 59 56 53
36 33 30 27 24 21 18
57 54 51 48 45 42 39
61 58 55 52 49 46 43
71 68 65 62 59 56 53
48 45 42 39 36 33 30
57 54 51 48 45 42 39
4) 3" diameter pipe can be used in place of 2" diameter pipe.
5) Increased Clearance Configurations using (2) 45 deg. Long Sweep el-
bows should be considered equivalent to one 90 deg. elbow.
V /F
ENT LUE AND
The vent/flue and combustion air pipes may terminate vertically, as
through a roof, or horizontally, as through an outside wall.
Vertical pipe terminations should be as shown in the following fig-
ure. Refer to Section IX, Vent/Flue Pipe and Combustion Pipe -
Termination Locations for details concerning location restrictions.
The penetrations through the roof must be sealed tight with proper
flashing such as is used with a plastic plumbing vent.
COMBUSTION
AIR INTAKE
12" MIN.
12" MIN.
TO ROOF OR
HIGHEST
ANTICIPATED
SNOW LEVEL
Horizontal terminations should be as shown in the following figure.
Refer to Section IX, Vent/Flue Pipe and Combustion Pipe - Termi-
nation Location for location restrictions. A 2 3/8 inch diameter wall
penetration is required for 2" diameter pipe while a 3 1/2 inch diam-
eter hole is required for 3" diameter pipe. To secure the pipe pass-
ing through the wall and prohibit damage to piping connections, a
coupling should be installed on either side of the wall and solvent
cemented to a pipe connecting the two couplings. The pipe length
should be the wall thickness plus the depth of the socket fittings to
7 8
be installed on the inside and outside of the wall. The wall penetra-
50
tion should be sealed with silicone caulking material.
37
28
50
15
36
50
36
28
14
Standard Horizontal Terminations (Dual Pipe)
7 8
28
50
15
36
40
50
27
36
Alternate Horizontal Vent Termination (Dual Pipe)
17
C A P T
OMBUSTION IR IPE ERMINATIONS
SCREEN
Vertical Terminations (Dual Pipe)
12" MIN
3" MIN
24" MAX
3" MIN
24" MAX
12" MIN.
TO ROOF OR
HIGHEST
ANTICIPATED
SN OW LEVEL
90°
MEDIUM
RADIUS
ELBOW
24" MAX
3" MIN
24" MAX
AIR
INTAKE
12" MIN. ABOVE
HIGHEST ANTICIPATED
SNOW LEVEL
VENT/FLUE
12" MIN.
TO ROOF OR
HIGHEST
ANTICIPATED
SNOW LEVEL