V-Typical Operating Conditions - Lennox ML193DFE Series Unit Information

V-TYPICAL OPERATING CHARACTERISTICS
A-Blower Operation and Adjustment1
NOTE- The following is a generalized procedure and does
not apply to all thermostat controls.
1 - Blower operation is dependent on thermostat control
system.
2 - Generally, blower operation is set at thermostat sub-
base fan switch. With fan switch in ON position, blower
operates continuously. With fan switch in AUTO position,
blower cycles with demand or runs continuously while
heating or cooling circuit cycles.
3 - Depending on the type of indoor thermostat, blower
and entire unit will be off when the system switch is in OFF
position.
B-Temperature Rise (FIGURE 55)
Temperature rise for ML196DF units depends on unit in-
put, blower speed, blower horsepower and static pressure
as marked on the unit rating plate. The blower speed must
be set for unit operation within the range of "TEMP. RISE
°F" listed on the unit rating plate.
TEMPERATURE RISE
Supply Duct Temperature
Return Duct Temperature
Temperature Rise =
FIGURE 55
_
Return
Supply
C-External Static Pressure
1 - Tap locations shown in FIGURE 56.
2 - Punch a 1/4" diameter hole in supply and return
air plenums. Insert manometer hose flush with
inside edge of hole or insulation. Seal around the
hose with permagum. Connect the zero end of the
manometer to the discharge (supply) side of the
system. On ducted systems, connect the other end
of manometer to the return duct as above.
3 - With only the blower motor running and the
evaporator coil dry, observe the manometer
reading. Adjust blower motor speed to deliver the
air desired according to the job requirements. For
heating speed external static pressure drop must
not be more than 0.5" W.C. For cooling speed
external static pressure drop must not be more than
0.8" W.C.
4 - Seal the hole when the check is complete.
EXTERNAL STATIC PRESSURE
Supply Duct Static
Return Duct Static +
Total Duct Static =
(dry coil)
D-Blower Speed Taps
Blower speed tap changes are made on the integrated
control (figure 3 or 5). The heating tap is connected to
the "HEAT" terminal and the cooling tap is connected to
the "COOL" terminal. On all units the continuous blower
tap is connected to the "FAN" terminal. Unused taps must
be secured on two dummy terminals labeled "PARK. To
change out existing speed tap, turn off power and switch
out speed tap with tap connected to "PARK". See blower
speed tap table on unit diagram for motor tap colors for
each speed.
Page 44
Return
+
−
or
High "+"
Supply
FIGURE 56
Low "-"