Carrier 58TUA - Manual (Page 6)

A89014
Fig. 6—Leveling Leg Installation
The gas supply line should be a separate line running directly from
the gas meter to the furnace, if possible. Refer to Table 4 for the
recommended gas pipe size. Risers must be used to connect to the
furnace and the meter.
A CAUTION
If a flexible connector is required or allowed by the authority
having jurisdiction, black iron pipe shall be installed at the
gas valve and extend a minimum of 2 in. outside the furnace
casing.
Table 4—Maximum Capacity of Pipe*
NOMINAL
IRON PIPE
SIZE (IN.)
INTERNAL
DIAMETER
(IN.)
LENGTH OF PIPE (FT)
10 20 30 40 50
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
1-1/4 1.380 1400 950 770 660 580
1-1/2 1.610 2100 1460 1180 990 900
* Cubic ft of gas per hr, for gas pressures of 0.5 psig (14-in. wc) or iess, and
a pressure drop of 0.5-in. wc (based on a 0.60 specific gravity gas). Ref: Table
10-2, NFPA 54-1992.
Piping should be pressure-tested in accordance with local and
national plumbing and gas codes before the furnace has been
attached. If the test pressure exceeds 0.5 psig (14-in. wc), the gas
supply pipe must be disconnected from the furnace and capped
before the pressure test. If the test pressure is equal to or less than
0.5 psig (14-in. wc), close the manual shutoff valve located on the
gas valve before the test. It is recommended that the ground joint
union be loosened before pressure testing. After all connections
have been made, purge the lines and check for leakage with
regulated gas supply pressure.
Install a sediment trap in the riser leading to the furnace. The trap
can be installed by connecting a tee to the riser leading from the
furnace. Connect a capped nipple into the lower end of the tee. The
capped nipple should extend below the level of the gas controls.
(See Fig. 7.)
Canadian installations must be installed in accordance with
CAN/CGA-B149 Installation Codes, and all authorities having
jurisdiction.
Fig. 7—^Typical Gas Pipe Arrangement
Apply joint compound (pipe dope) sparingly and only to the male
threads of each joint. The compound must be resistant to the action
of propane gas.
Install an accessible manual shut-off valve upstream of the furnace
gas controls and within 72 in. of the furnace. A 1/8-in. NPT
plugged tapping, accessible for test gage connection, must be