Goodman GMVC950704CX Installation Instructions Manual page 19

Direct Vent (Dual Pipe) Maximum Allowable Length*
of Vent/Flue & Combustion Air Intake Pipe
(4)
Unit Input Termination
Pipe
(Btu) Style
(inch)
Standard 2 or 2 1/2
45,000
Alternate 2 or 2 1/2
2 or 2 1/2
Standard
3
70,000
2 or 2 1/2
Alternate
3
Standard 3
90,000
Alternate 3
Standard 3
115,000
Alternate 3
*Maximum allowable limits listed are individual lengths for inlet & flue and NOT a combination.
COUNTERFLOW
Direct Vent (Dual Pipe) Maximum Allowable Length*
of Vent/Flue & Combustion Air Intake Pipe
(4)
Unit Input Termination
Pipe
(Btu) Style
(inch)
2 or 2 1/2
Standard
3
70,000
2 or 2 1/2
Alternate
3
2 or 2 1/2
Standard
3
90,000
2 or 2 1/2
Alternate
3
Standard 3
115,000
Alternate 3
*Maximum allowable limits listed are individual lengths for inlet & flue and NOT a combination.
1) Elbows and/or tees used in terminations must be included when determin-
ing 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.
4) 2 1/2" or 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.
Vertical pipe terminations should be as shown in the following
figure. Refer to Vent/Flue Pipe and Combustion Pipe - Termina-
tion 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.
UPFLOW
(ft)
(1)(2)(3)(5)
Number of Elbows
1 2 3 4 5 6
71 68 65 62 59 56
58 55 52 49 46 43
49 46 43 40 37 34
71 68 65 62 59 56
36 33 30 27 24 21
57 54 51 48 45 42
71 68 65 62 59 56
57 54 51 48 45 42
49 46 43 40 37 34
35 32 29 26 23 20
(ft)
(1)(2)(3)(5)
Number of Elbows
1 2 3 4 5 6
49 46 43 40 37 34
71 68 65 62 59 56
36 33 30 27 24 21
57 54 51 48 45 42
61 58 55 52 49 46
71 68 65 62 59 56
48 45 42 39 36 33
57 54 51 48 45 42
71 68 65 62 59 56
57 54 51 48 45 42
V /F P
ENT LUE IPE
7 8
53 50
40 37
31 28
53 50
18 15
39 36
53 50
39 36
31 28
17 14
7 8
31 28
53 50
18 15
39 36
43 40
53 50
30 27
Horizontal terminations should be as shown in the following figure.
39 36
Refer to Vent/Flue Pipe and Combustion Pipe - Termination Loca-
53 50
tion for location restrictions. A 2 3/8" diameter wall penetration is
39 36
required for 2" diameter pipe. A 3" diameter hole is required for a 2
1/2" pipe and a 3 1/2" diameter hole is required for 3" diameter
pipe. To secure the pipe passing 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 be installed on the inside
and outside of the wall. The wall penetration should be sealed with
silicone caulking material.
3" MIN
24" MAX
3" MIN
24" MAX
MEDIUM RADIUS
ELBOW
SCREEN
Standard Horizontal Terminations (Dual Pipe)
19
& C
OMBUSTION
TEE (OPTIONAL)
COMBUSTION
AIR INTAKE
12" MIN.
SCREEN
12" MIN. TO ROOF
OR HIGHEST ANTICIPATED
SNOW LEVEL
12" MIN.
SCREEN
12" MIN. TO ROOF
OR HIGHEST ANTICIPATED
SNOW LEVEL
Vertical Terminations (Dual Pipe)
12" MIN
90º
12" MIN. TO ROOF OR
HIGHEST ANTICIPATED
SNOW LEVEL
A P
IR IPE
VENT/FLUE
VENT/FLUE
12" MIN. TO ROOF OR
HIGHEST ANTICIPATED
SNOW LEVEL