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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 thermosta control
system
2 - Generally, blower operation is set at thermostat
subbase 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 59)
Temperature rise for ML196UH 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 = ________
SUPPLY
AIR
Temperatures
RETURN AIR
FIGURE 59
C-External Static Pressure
1 -
Tap locations shown in FIGURE 60.
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 _____
Total Duct Static = ________ (dry coil)
Duct Static
or
Supply Air
Return Air
FIGURE 60
D-Blower Speed Taps
Blower speed tap changes are made on the integrated
control. See FIGURE 3 or FIGURE 5. The heating tap is
connected to the “HEAT” terminal and the cooling tap is
connected to the “COOL” terminal. On all units the con
-
tinuous 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.
Summary of Contents for ML196UH030XE36B
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