Carrier 58 Series - Manual (Page 4)

GAS PIPING
The gas supply line should be a separate line
directly from the meter to the furnace, if possible.
Refer to Table 1 for recommended gas pipe sizing.
Do not use cast-iron or galvanized pipe.
Table 1 — Maximum Capacity of Gas Pipe*
NOMINAL
I R O N PIPE
SIZE
(in.)
Z
’ " 3 / 4
1 T
1 - 1 / 4
1 - 1 / 2
INTERNAL
DIAMETER
(in.)
”^622~
0 824
1^049
1 380
1 6 IO"
LENGTH OF PIPE
(ft)
10_
r''
360
68Í
1400
2100
20 30 40 50
120 97 82 73
250 200 170 151
465 375 320 285
950 770 660 580
1460 1180 990 900
*Cu ft of gas per hour for gas pressures of 0 5 psig or less, and a
pressure drop of 0 5 in wg (based on a 0 60 specific gravity)
Ref Table C-4 NFPA 54-1980
Avoid low spots in long runs of pipe. It is best to
slope all pipe 1/4in. in 15ft to prevent traps. All
horizontal runs should slope away from the meter,
to risers. Risers should be used to connect to the
furnace and to the meter.
Joint compounds (pipe dope) should be applied
sparingly and only to the male threads of the joints
(omit the first 2 threads). Consult local supplier for
type of compound to be used. This pipe dope must
be resistant to the action of LP gas.
Install a sediment trap in the riser leading to the
furnace. This trap will collect dirt or condensate. It
can be installed by connecting a tee to the riser lead­
ing to the furnace, so that the straight-thru section of
the tee is vertical. Then 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. 3.
Where a gum filter is required by local codes, install
it in accordance with those requirements.
An accessible manual shutoff valve shall be in­
stalled upstream of the furnace gas controls and
within 6 ft of the furnace. A 1/8-in. NPT plugged
tapping, accessible for test gage connection, must
be installed immediately upstream of the gas supply
connection to the furnace and downstream from
the manual shutoff valve.
Place a ground joint union between the gas con­
trol manifold and the manual gas shutoff valve, or
use an approved flexible or semirigid conductor.
Support all piping with the appropriate straps,
hangers, etc. (one hanger every 10 ft minimum).
Piping should be pressure-tested before any
furnace, appliance, or shutoff valve is attached, in
accordance with the requirements of local and
national plumbing and gas codes.
If the pressure exceeds 0.5 psig, the gas supply
pipe must be disconnected from the furnace before
the pressure test. If the test pressure is equal to or
less than 0.5 psig, close the manual shutoff valve
located on the gas valve before the test. It is recom­
mended that the ground joint union be cracked be­
fore pressure testing.
After all connections have been made, purge the
lines and check for leakage.
WARNING: Never purge a fine into a combus­
tion chamber. Never use matches, candles,
ñame or other sources of ignition for the pur­
pose of checking leakage. Use a soap-and-water
solution to check for leakage.
Fig. 3 — Sediment Trap
- VENTING
Consult local codes. For additional information
refer to the “National Fuel Gas Code” (NFPA No.
54-1980 or ANSI Z223.1-1980). Unless the local
codes direct otherwise, the unit may be vented to a
permanent chimney, or to a listed type-B 1 gas vent.
All gas-fired furnaces are shipped with draft
diverters; therefore, connect the vent collar to the
chimney or gas vent to be used. The following
recommendations are made:
1. Select flue connection material that is satis­
factory for installation and that meets require­
ments of local codes.
2. Flue connection pipe must be at least as large as
outlet collar on furnace. No reduction in this
size is permissible in pipe run.
3. Run pipe as directly as possible with minimum
number of turns.
Maintain minimum of 1/4in. per linear ft up­
ward slope on all horizontal runs.
Rigidly support flue pipe with hangers and
straps to ensure that there will no movement
after installation.
4.