Carrier 58MCA Installation, Start-Up, And Operating Instructions Manual page 27

ALTITUDE UNIT SIZE
040-08
040-12
060-08
060-12
060-16
080-12
8001 to
080-16
9000‡
080-20
100-16
100-20
120-20
140-20
ALTITUDE UNIT SIZE
040-08
040-12
060-08
060-12
060-16
080-12
9001 to
080-16
10,000‡
080-20
100-16
100-20
120-20
140-20
* Disk usage—Unless otherwise specified, use perforated disk assembly (factory-supplied in loose parts bag). If one disk is stated, separate 2 halves of perforated disk
assembly and use shouldered disk half. When using shouldered disk half, install screen side toward inlet box.
† Wide radius elbow.
‡ Vent sizing for Canadian installations over 4500 ft (1370 m) above sea level are subject to acceptance by the local authorities having jurisdiction.
NA—Not Allowed; pressure switch will not make.
NOTES:
1. Do not use pipe size greater than those specified in table or incomplete combustion, flame disturbance, or flame sense lockout may occur.
2. Size both the combustion-air and vent pipe independently, then use the larger diameter for both pipes.
3. Assume two 45° elbows equal one 90° elbow. Long radius elbows are desirable and may be required in some cases.
4. Elbows and pipe sections within the furnace casing and at the vent termination should not be included in vent length or elbow count.
5. The minimum pipe length is 5 ft for all applications.
6. Use 3-in. diameter vent termination kit for installations requiring 4-in diameter pipe.
COMBUSTION – AIR
INTAKE HOUSING
3/8" ID TUBE
3/16"
DRILL
4
MIN
TRAP
TO OPEN
DRAIN
Fig. 29—Intake Housing Plug Fitting Drain
NOTE: See label on vent extension pipe for proper installation.
This pipe may be shortened if an elbow is used to connect vent
extension tube to field-installed vent pipe.
3. Working from furnace to outside, cut pipe to required
length(s).
4. Deburr inside and outside of pipe.
5. Chamfer outside edge of pipe for better distribution of primer
and cement.
Table 6—Maximum Allowable Pipe Length (Ft)
TERMINATION
TYPE
2 Pipe or 2-In.
Concentric
2 Pipe or 2-In.
Concentric
2 Pipe or 2-In.
Concentric
2 Pipe or 3-In.
Concentric
2 Pipe or 3-In.
Concentric
TERMINATION
TYPE
2 Pipe or 2-In.
Concentric
2 Pipe or 2-In.
Concentric
2 Pipe or 2-In.
Concentric
2 Pipe or 3-In.
Concentric
2 Pipe or 3-In.
Concentric
BURNER
BOX
COMBUSTION –
AIR PIPE
A93035
PIPE DIA
(IN.)*
1 2
1-1/2 46 41
2 62 60
1-1/2 11 6
2 49 44
2 33 28
2-1/2 62 60
2-1/2 23 15
3 59 54
3† no disk 10 NA
4† no disk 35 30
NA
PIPE DIA
(IN.)*
1 2
1-1/2 42 37
2 57 55
2 45 40
2 30 25
2-1/2 57 55
2-1/2 21 13
3 54 49
4† no disk 10 5
NA
6. Clean and dry all surfaces to be joined.
7. Check dry fit of pipe and mark insertion depth on pipe.
NOTE: It is recommended that all pipes be cut, prepared, and
preassembled before permanently cementing any joint.
8. After pipes have been cut and preassembled, apply generous
layer of cement primer to pipe fitting socket and end of pipe
to insertion mark. Quickly apply approved cement to end of
pipe and fitting socket (over primer). Apply cement in a light,
uniform coat on inside of socket to prevent buildup of excess
cement. Apply second coat.
9. While cement is still wet, twist pipe into socket with 1/4 turn.
Be sure pipe is fully inserted into fitting socket.
10. Wipe excess cement from joint. A continuous bead of cement
will be visible around perimeter of a properly made joint.
11. Handle pipe joints carefully until cement sets.
12. Support combustion-air and vent piping a minimum of every
5 ft (3 ft for SDR-21 or -26 PVC) using perforated metal
hanging strap.
13. Slope combustion-air and vent pipes toward furnace a mini-
mum of 1/4 in. per linear ft with no sags between hangers.
14. Use appropriate methods to seal openings where vent and
combustion-air pipes pass through roof or side wall.
27
Continued
NUMBER OF 90° ELBOWS
3 4 5
36 31 29
58 56 55
NA NA NA
42 37 35
17 12 10
58 56 55
7 5 NA
49 44 39
NA NA NA
25 20 15
NUMBER OF 90° ELBOWS
3 4 5
32 27 25
53 51 49
38 33 31
14 9 7
53 51 49
5 NA NA
44 39 34
NA NA NA
6
24
53
NA
34
NA
53
NA
34
NA
10
6
20
47
29
NA
47
NA
29
NA