Carrier WeatherExpert 48JC04, Руководство по установке

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The gas supply pipe enters the unit at the burner access panel
on the front side of the unit, through the long slot at the bottom
of the access panel. The gas connection to the unit is made to
the
1
/
2
-in. FPT gas inlet port on the unit gas valve.
Manifold pressure is factory-adjusted for natural gas fuel use.
Adjust as required to obtain best flame characteristics. See
Table 5.
Manifold pressure for LP fuel use must be adjusted to specified
range. Follow instructions in the accessory kit to make initial
readjustment, see Table 6.
Install a gas supply line that runs to the unit heating section.
Refer to the NFPA 54/NFGC or equivalent code for gas pipe
sizing data. Do not use a pipe size smaller than
1
/
2
-in. Size the
gas supply line to allow for a maximum pressure drop of
0.5 in. wg (124 Pa) between gas regulator source and unit gas
valve connection when unit is operating at high-fire flow rate.
The gas supply line can approach the unit in three ways: hori -
zontally from outside the unit (across the roof), thru-curb/under
unit basepan (accessory kit required), or through unit basepan
(factory option or accessory kit required). Consult accessory
kit installation instructions for details on these installation
methods. Observe clearance to gas line components per
Fig. 16.
Fig. 16 — Gas Piping Guide
(with Accessory Thru-the-Curb Service Connections)
FACTORY OPTION THRU-BASE CONNECTIONS (GAS
CONNECTIONS)
This service connection kit consists of a
1
/
2
-in. electrical bulkhead
connector and a
3
/
4
-in. electrical bulkhead connector, connected to
an “L” bracket covering the embossed (raised) section of the unit
basepan in the condenser section (see Fig. 17 for shipping
position).
The
3
/
4
-in. bulkhead connector enables the low-voltage control
wires to pass through the basepan. The
1
/
2
-in. bulkhead connector
allows the high-voltage power wires to pass through the basepan.
See Fig. 18.
Table 3 — Natural Gas Supply Line Pressure Ranges
UNIT MODEL UNIT SIZE MIN. MAX.
48JC
04, 05, 06
4.0 in. wg
(996 Pa)
13.0 in. wg
(3240 Pa)
Table 4 — Liquid Propane Supply Line Pressure
Ranges
UNIT MODEL UNIT SIZE MIN. MAX.
48JC
04, 05, 06
11.0 in. wg
(2740 Pa)
13.0 in. wg
(3240 Pa)
Table 5 — Natural Gas Manifold Pressure Ranges
UNIT MODEL UNIT SIZE HIGH FIRE LOW FIRE
48JC
04, 05, 06
3.5 in. wg
(872 Pa)
1.7 in. wg
(423 Pa)
Table 6 — Liquid Propane Manifold Pressure Ranges
UNIT MODEL UNIT SIZE HIGH FIRE LOW FIRE
48JC 04, 05, 06
10 in. wg
(2490 Pa)
5 in. wg
(1245 Pa)
CAUTION
EQUIPMENT DAMAGE
Failure to follow this caution may result in equipment dam -
age.
When connecting the gas line to the unit gas valve, the in -
staller MUST use a backup wrench to prevent damage to
the valve.
X
BASE UNIT
BASE RAIL
ROOF
CURB
9” MINIMUM CLEARANCE
FOR PANEL REMOVAL
MANUAL GAS
SHUTOFF VALVE
*
GAS
REGULATOR
*
48” MINIMUM
DRIP LEG
PER NFGC
*
FIELD-FABRICATED
SUPPORT
*
FROM
GAS
METER
LEGEND *Field supplied.
NOTE: Follow all local codes.
NFGC — National Fuel Gas
Code
STEEL PIPE
NOMINAL DIAMETERS (IN.)
SPACING OF SUPPORTS
X DIMENSION (FT)
1 /
2
6
3
/
4
or 1
8
1 1 /
4
or larger 10