5725848-XIM-A-0319
Johnson Controls Ducted Systems
15
1.
The vaporization rate depends on (a) the temperature of
the liquid and (b) the “wetted surface” area of the container
or containers.
2.
The proper pressure regulation. (Two-stage regulation is
recommended from the standpoint of both cost and
efficiency.)
3.
The pressure drop in the lines between regulators and
between the second stage regulator and the appliance.
Pipe size required will depend on the length of the pipe run
and the total load of all appliances.
Complete information regarding tank sizing for vaporization,
recommended regulator settings, and pipe sizing is available
from most regulator manufacturers and L.P./propane gas
suppliers.
L.P./propane gas is an excellent solvent and special pipe
compound must be used when assembling piping for this gas
as it will quickly dissolve white lead or most standard
commercial compounds. Shellac base compounds such as
Rectorseal #5 are satisfactory for this type of gas.
Check all connections for leaks when piping is com-
pleted, using a soap solution.
NEVER USE A FLAME
.
Vent and combustion air hoods
The vent hood and combustion air hood (with screens) are
shipped attached to the blower housing in the blower
compartment. These hoods must be installed to assure proper
unit function. All hoods must be fastened to the outside of the
gas heat access panel with the screws provided in the bag also
attached to the blower housing.
The screen for the combustion air intake hood is secured to the
inside of the access panel opening with three fasteners and the
screws used for mounting the hood to the panel. The top flange
of this hood slips in under the top of the access panel opening
when installing. Refer to Vent and Combustion Air Hood Figure
7.
The vent hood is installed by inserting the top flange of the hood
into the slotted opening in the access panel and securing in
place.
The products of combustion are discharged horizontally
through this screened, hooded vent openings on the gas heat
access panel.
Optional economizer/motorized damper rain hood
The instruction for the optional economizer/motorized damper
rain hood can be found in form 5004998 Use these instructions
when field assembling an economizer rain hood onto a unit.
The outdoor and return air dampers, the damper actuator, the
damper linkage, the outdoor and return air divider baffles, and
all the control sensors are factory mounted as part of the
“Factory installed” economizer option.
Optional power exhaust/barometric relief damper and rain
hood
The instructions for the power exhaust/barometric relief damper
and rain hood can be found in form 1200060. The exhaust fan,
all supporting brackets, angles, and the wiring are factory
installed as part of the power exhaust option.
All of the components, including the dampers, hardware, and
mounting instructions are shipped in a single package external
from the unit. The hood must be field assembled and installed.
Power exhaust is only available as a field installed accessory.
Figure 6: Bottom supply connection external shut-off
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warning exactly could
result in serious injury, death or property dam-
age.
Never test for gas leaks with an open flame. use
a commercially available soap solution made
specifically for the detection of leaks to check all
connections. A fire or explosion may result caus-
ing property damage, personal injury or loss of
life.
Figure 7: Vent and combustion air hood
