13
Fig. 16 — Flue Hood Details
Step 11 — Install Gas Piping
Installation of the gas piping must be accordance with lo-
cal building codes and with applicable national codes. In
U.S.A., refer to NFPA 54/ANSI Z223.1 National Fuel Gas
Code (NFGC). In Canada, installation must be accordance
with the CAN/CSA B149.1 and CAN/CSA B149.2 installa-
tion codes for gas burning appliances.
This unit is factory equipped for use with Natural Gas fuel at
elevations up to 2000 ft (610 m) above sea level. Unit may be
field converted for operation at elevations above 2000 ft (610 m)
and/or for use with liquefied petroleum fuel. See accessory kit
installation instructions regarding these accessories.
NOTE: Furnace gas input rate on rating plate is for installation
up to 2000 ft (610 m) above sea level. The input rating for alti-
tudes above 2000 ft (610 m) must be derated by 4% for each
1000 ft (305 m) above sea level.
For natural gas applications, gas pressure at unit gas con-
nection must not be less than 4 in. wg (996 Pa) or greater than
13 in. wg (3240 Pa) while the unit is operating. On
48KCF*05-06 (high-heat) units, the gas pressure at unit gas
connection must not be less than 5 in. wg (1245 Pa) or greater
than 13 in. wg (3240 Pa) while the unit is operating, see
Table 3. For liquified petroleum applications, the gas pressure
must not be less than 11 in. wg (2740 Pa) or greater than 13.0
in. wg (3240 Pa) at the unit connection, see Table 4.
Table 3 — Natural Gas Supply Line Pressure
Ranges
Table 4 — Liquid Propane Supply Line Pressure
Ranges
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.
Table 5 — Natural Gas Manifold Pressure Ranges
Manifold pressure for LP fuel use must be adjusted to speci-
fied range. Follow instructions in the accessory kit to make ini-
tial readjustment, see Table 6.
Table 6 — Liquid Propane Manifold Pressure
Ranges
Install a gas supply line that runs to the unit heating sec-
tion. 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:
horizontally 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 in-
stallation methods. Observe clearance to gas line components
per Fig. 17.
UNIT MODEL UNIT SIZE MIN. MAX.
48KCD/E/L/M/S/R 04, 05, 06
4.0 in. wg
(996 Pa)
13.0 in. wg
(3240 Pa)
48KCF/N/T
(High Heat Units Only)
05, 06
5.0 in. wg
(1245 Pa)
13.0 in. wg
(3240 Pa)
UNIT MODEL UNIT SIZE MIN. MAX.
48KCD/E/S/R 04, 05, 06
11.0 in. wg
(2740 Pa)
13.0 in. wg
(3240 Pa)
48KCF/T
(High Heat Units Only)
05, 06
11.0 in. wg
(2740 Pa)
13.0 in. wg
(3240 Pa)
BLOWER
ACCESS
PANEL
FLUE OPENING
UNIT MODEL UNIT SIZE HIGH FIRE LOW FIRE
48KCD/E/L/M/S/R 04, 05, 06
3.5 in. wg
(872 Pa)
SEE NOTE
BELOW
48KCF/N/T
(High Heat Units Only)
05, 06
3.5 in. wg
(872 Pa)
SEE NOTE
BELOW
NOTE: LOW FIRE, 1.7 in. wg (423 Pa), applies to the following three
phase voltage units only: 48KCE*04 and 48KCF*05/06.
UNIT MODEL UNIT SIZE HIGH FIRE LOW FIRE
48KCD/E/S/R 04, 05, 06
10 in. wg
(2490 Pa)
SEE NOTE
BELOW
48KCF/T
(High Heat Units Only)
05, 06
10 in. wg
(2490 Pa)
SEE NOTE
BELOW
NOTE: LOW FIRE, 5.0 in. wg (1245 Pa), applies to the following
three phase voltage units only: 48KCE*04 and 48KCF*05/06.
CAUTION
Failure to follow this caution may result in equipment dam-
age.
When connecting the gas line to the unit gas valve, the
installer MUST use a backup wrench to prevent damage to
the valve.
To Next Page
Loading...
