Carrier 58MXA Operating And Instruction Manual page 25

ALTITUDE UNIT SIZE
040-08
040-12
060-08
060-12
060-16
080-12
9001 to 10,000‡
080-16
080-20
100-16
100-20
120-20
* Disk usage—Unless otherwise specified, use perforated disk assembly (factory-supplied in loose parts bag). If stated, separate 2 halves of perforated disk assembly
and use shouldered disk half or no disk assembly.
† 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.
attached by using RTV sealant, or by drilling a 1/8-in. hole in
fitting, using hole in intake housing as a guide. Install a
field-supplied No. 6 or No. 8 sheet metal screw.
NOTE: DO NOT OVERTIGHTEN SCREW. Breakage to intake
housing or fitting may cause air leakage to occur.
A plugged drain connection has been provided on this fitting
for use when moisture is found in combustion-air intake pipe
and combustion box.
NOTE: Moisture in combustion-air intake may be result of
improper termination. Ensure combustion-air intake pipe is similar
to that shown in Fig. 31, 32, 33, 34, or 35 so it will not be
susceptible to areas where light snow or other sources of moisture
could be pulled in.
If use of this drain connection is desired, drill out fitting's tap
plug with a 3/16-in. drill and connect a field-supplied 3/8-in.
tube. This tube should be routed to open condensate drain for
furnace and A/C (if used), and should be trapped. (See Fig.
30.)
2. Attach vent pipe as follows:
a. Determine location of vent pipe connection to inducer
housing as shown in Fig. 28 for application.
b. Reposition neoprene inducer housing outlet cap and clamp
to appropriate unused inducer housing connection. Tighten
clamp.
Inducer housing outlet cap must be installed and fully seated
against inducer housing. Clamp must be tightened to prevent
any condensate leakage. Failure to follow this warning could
result in electrical shock, fire, personal injury, or death.
c. Install pipe support (factory-supplied in loose parts bag)
into selected furnace casing vent pipe hole. Pipe support
should be positioned at bottom of casing hole.
d. Insert 2-in. diameter pipe into inducer housing through
neoprene coupling and clamp in inducer housing. Tighten
clamp.
Table 5—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
Continued
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
3† one disk 18 16
3† no disk 39 37
3/8" ID TUBE
3/16"
DRILL
4"
MIN
TRAP
TO OPEN
DRAIN
Fig. 30—Intake Housing Plug Fitting Drain
Vent pipe must be installed and fully seated against inducer
housing. Clamp must be tightened to prevent any condensate
leakage. Failure to follow this warning could result in
electrical shock, fire, personal injury, or death.
NOTE: A 2-in. diameter pipe must be used within the furnace
casing. Make all pipe diameter transitions outside furnace casing.
VENT EXTENSION PIPE
Some furnaces are supplied with a PVC vent extension pipe
(2-in. diameter by 12-in. long). This pipe has a built-in
channel to assist vent condensate disposal. When this vent
extension pipe is supplied, it must be used to connect the field
vent pipe to furnace inducer housing on ALL upflow and
downflow applications.
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.
25
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
14 9 7
35 33 31
COMBUSTION – AIR
INTAKE HOUSING
BURNER
BOX
COMBUSTION –
AIR PIPE
6
20
47
29
NA
47
NA
29
5
29
A93035