Table 3 – Maximum Capacity of Pipe*
NOMINAL | INTERNAL |
| LENGTH OF PIPE (FT/M) |
| |||
IRON |
|
| |||||
|
|
|
|
| |||
PIPE | DIAMETER |
|
|
|
|
| |
10/ | 20/ | 30/ | 40/ | 50/ | |||
SIZE | (IN.) | ||||||
3.0 | 6.1 | 9.1 | 12.2 | 15.2 | |||
(IN.) |
| ||||||
|
|
|
|
|
| ||
1/2 | 0.622 | 175 | 120 | 97 | 82 | 73 | |
3/4 | 0.824 | 360 | 250 | 200 | 170 | 151 | |
1 | 1.049 | 680 | 465 | 375 | 320 | 285 | |
1.380 | 1400 | 950 | 770 | 660 | 580 | ||
1.610 | 2100 | 1460 | 1180 | 990 | 900 |
*Cubic ft of gas per hr for gas pressure of 0.5 psig
NOTE: The gas valve inlet pressure tap connection is suitable to use as test gauge connection providing test pressure DOES NOT exceed maximum 0.5 psig
Piping should be pressure and leak tested in accordance with NFGC in the United States or
If test pressure is equal to or less than 0.5 psig
The gas supply pressure shall be within the maximum
Electrical Connections
See Fig. 29 for field wiring diagram showing typical field
!WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Blower access door switch opens
!WARNING
UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent unit operation.
Furnace control must be grounded for proper operation or control will lock out. Control is grounded through green/yellow wire connected to gas valve and burner box screw.
115-v Wiring
Before proceeding with electrical connections, make certain that voltage, frequency, and phase correspond to that specified on furnace rating plate. Also, check to be sure that service provided by power supply is sufficient to handle load imposed by this equipment. Refer to rating plate or Table 4 for equipment electrical specifications.
Make all electrical connections in accordance with National Electrical Code (NEC) ANSI/NFPA
The furnace must be electrically grounded in accordance with local codes; or in the absence of local codes, with the National Electric Code ANSI/NFPA 70 and/or the Canadian Electric Code, CSA C22.1, Part I, if an external electrical source is utilized.
Use a separate branch electrical circuit containing a properly sized fuse or circuit breaker for this furnace. See Table 4 for wire size and fuse specifications. A disconnecting means must be located within sight from and readily accessible to furnace.
NOTE: Proper polarity must be maintained for
!WARNING
FIRE HAZARD
Failure to follow this warning could result in personal injury, death, or property damage.
Do not connect aluminum wire between disconnect switch and furnace. Use only copper wire. (See Fig. 30.)
355CAV
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