18-CD35D1-1 29
INSTALLER’S GUIDE
closing its individual manual shut-off valve during any pressure
testing of the gas supply piping system at test pressures equal to
or less than 1/2 psig (3.5 kPa).
NOTE: Maximum pressure to the gas valve for
natural gas is 13.8" W.C. Minimum pressure is
5.0" W.C. Maximum pressure to the gas valve
for propane is 13.8" W.C. Minimum pressure is
11.0" W.C.
All gas fittings must be checked for leaks using
a soapy solution before lighting the furnace.
DO NOT CHECK WITH AN OPEN FLAME!
▲
CAUTION
!
Use a backup wrench on the gas valve when
installing gas piping to prevent damage to the
gas valve and manifold assembly.
UPFLOW – LEFT HAND GAS PIPING
UPFLOW – RIGHT HAND GAS PIPING
W
AUTOMATIC GAS VALVE
WITH MANUAL SHUTOFF
MAIN MANUAL
SHUTOFF VALVE
GROUND
UNION
JOINT
DRIP
LEG
AUTOMATIC GAS VALVE
WITH MANUAL SHUTOFF
MAIN MANUAL
SHUTOFF VALVE
GROUND
UNION
JOINT
DRIP
LEG
GAS PIPING
The upflow/ horizontal furnace is shipped standard for left side
installation of gas piping. A knock-out is provided on the right
side for an alternate gas piping arrangement. See Figure 52.
The installation of piping shall be in accordance with piping
codes and the regulations of the local gas company. Pipe joint
compound must be resistant to the chemical reaction with
liquefied petroleum gases.
Refer to piping Table 15, for delivery sizes. Connect gas supply
to the unit, using a ground joint union and a manual shut-off
valve as shown in Figure 52-53.
National codes require a condensation drip leg to be installed
ahead of the controls as shown in Figure 52-53.
The furnace and its individual shut-off valve must be disconnected
from the gas supply piping system during any pressure testing of
that system at test pressures in excess of 1/2 psig (3.5 kPa).
The furnace must be isolated from the gas supply piping by
THE DOWNFLOW (VERTICAL) MAY BE INSTALLED LEFT OR RIGHT SIDE GAS PIPING
E