York PREDATOR DR120 - Manual (Page 28)

127878-YIM-B-0606
28 Unitary Products Group
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 con-
tainer(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.
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.
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 cham-
ber. All electric heaters are fused and intended for use with
single point power supply.
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 com-
plete the assembly. Field installed Motorized Outdoor
Damper accessories include complete instructions for instal-
lation.
ECONOMIZER
The Economizer can be a factory installed option or a field
installed accessory. If factory installed, refer to the instruc-
tions included with the outdoor air hood to complete the
assembly. Field installed Economizer accessories include
complete instructions for installation.
There are two Economizer options:
1. Down Flow application with barometric relief hood stan-
dard.
2. Horizontal Flow application that requires the purchase of
a barometric relief hood.
POWER EXHAUST
The Power Exhaust can be a factory installed option or a field
installed accessory. If factory installed, refer to the instruc-
tions included with the outdoor air hood to complete the
assembly. Field installed Power Exhaust accessories include
complete instructions for installation.
The Power Exhaust factory installed option is for Down Flow
application only.
There are two field installed Power Exhaust accessories:
1. Down Flow application.
2. Horizontal Flow application that requires the purchase of
a barometric relief hood.
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 specifi-
cally for the detection of leaks to check all connec-
tions. A fire or explosion may result causing property
damage, personal injury or loss of life.