5326602-XIM-B-1019
Johnson Controls Ducted Systems
27
For satisfactory operation, LP gas pressure must be 10.5 inch
W.C. at the unit under full load. Maintaining proper gas
pressure depends on three main factors:
1.
The vaporization rate which depends on the temperature of
the liquid and the “wetted surface” area of the container(s).
2.
The proper pressure regulation. (Two-stage regulation is
recommended).
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 LP gas suppliers.
Check all connections for leaks when piping is completed using
a soap solution.
NEVER USE A FLAME.
Vent And Combustion Air
Venting slots in the heating compartment access panel remove
the need for a combustion air hood. The gas heat flue exhaust
is routed through factory installed exhaust piping with screen. If
necessary, a flue exhaust extension may be installed at the
point of installation.
Options/Accessories
Electric Heat
Electric heaters are available as factory-installed options or
field-installed accessories. Refer to electric heat instructions for
installation. These heaters mount in the heat compartment with
the heating elements extending into the supply air chamber. All
electric heaters are fused and intended for use with single point
power supply.
Smoke Detectors
The factory-installed smoke detector will shut down operation of
the unit by interrupting power to the UCB when smoke is
detected within its mounting compartment. The smoke detector
option is available for both supply and/or return air configura-
tions. Be aware that the supply air configuration has the sensor
component mounted in the blower section, with its control mod-
ule mounted in the return air compartment.
The detector must be tested and maintained on a regular basis
according to NFPA 72 requirements and cleaned at least once
a year. For specific troubleshooting and maintenance
procedures, please refer to the smoke detector's installation
instructions which accompanies the unit.
Motorized Outdoor Damper
The Motorized Outdoor Damper can be a factory installed
option or a field installed accessory. If factory installed, refer to
the instructions included with the outdoor air hood to complete
LP gas is an excellent solvent and will quickly dissolve
white lead and most standard commercial compounds. A
special pipe dope must be used when assembling
wrought iron or steel pipe for LP. Shellac base
compounds such as Gaskolac or Stalastic, and
compounds such as Rectorseal #5, Clyde’s, or John
Crane may be used.
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warning exactly could result
in serious injury, death or property damage.
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 causing property damage,
personal injury or loss of life.
The use of duct smoke detectors have specific limitations
as established by the National Fire Protection
Association. Duct smoke detectors are; NOT a substitute
for an open area smoke detector, NOT a substitute for
early warning detection, and NOT a replacement for a
building's regular fire detection system. Refer to NFPA
Code 72 and Standard 90A for additional information.
Factory-installed smoke detectors may be subjected to
extreme temperatures during "off" times due to outside air
infiltration. These smoke detectors have an operational
limit of -4°F to 158°F. Smoke detectors installed in areas
that could be outside this range will have to be relocated to
prevent false alarms.
To assure adequate airflow reaches the smoke detector's
sensor, make sure that the holes of the sampling tube
face into the air stream, and that the far-end of the
sampling tube is sealed with the plastic end cap.
In addition, the unit's supply airflow must be adjusted to
provide a pressure differential across the smoke
detector's sampling and exhaust ports of at least 0.01
inches of water and no more than 1.11 inches of water, as
measured by a manometer.
