Carrier WeatherMaster 48HC07-12 Installation Instructions Manual page 64

VERIFY SMOKE DETECTOR UNIT SHUTDOWN BY UTILIZING MAGNET TEST
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III. HUMIDI-MIZER SYSTEM START-UP
STEPS
1. CHECK CTB FOR JUMPER 5, 6, 7

JUMPER 5, 6, 7 MUST BE CUT AND OPEN
2. OPEN HUMIDISTAT CONTACTS
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3. START UNIT IN COOLING (CLOSE Y1)
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OBSERVE AND RECORD
A. SUCTION PRESSURE
B. DISCHARGE PRESSURE
C. ENTERING AIR TEMPERATURE
D. LIQUID LINE TEMPERATURE
AT OUTLET OR REHEAT COIL
E. CONFIRM CORRECT ROTATION FOR COMPRESSOR
F. CHECK FOR CORRECT RAMP-UP OF OUTDOOR FAN MOTOR AS CONDENSER COIL WARMS
4. CHECK UNIT CHARGE PER CHARGING CHART

5. SWITCH UNIT TO HIGH-LATENT MODE (SUBCOOLER) BY CLOSING HUMIDISTAT WITH Y1 CLOSED

OBSERVE
A. REDUCTION IN SUCTION PRESSURE (5 TO 7 PSI EXPECTED)

B. DISCHARGE PRESSURE UNCHANGED

C. LIQUID TEMPERATURE DROPS TO 50 TO 55°F RANGE
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D. LIQUID SOLENOID VALVE (LSV) ENERGIZED (VALVE CLOSES)
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6. SWITCH UNIT TO DEHUMID (REHEAT) BY OPENING Y1

OBSERVE
A. SUCTION PRESSURE INCREASES TO NORMAL COOLING LEVEL

B. DISCHARGE PRESSURE DECREASES (35 TO 50 PSI)

C. LIQUID TEMPERATURE RETURNS TO NORMAL COOLING LEVEL

D. LIQUID SOLENOID VALVE (LSV) ENERGIZED (VALVE CLOSES)

E. DISCHARGE SOLENOID VALVE (DSV) ENERGIZED, VALVE OPENS

7. WITH UNIT IN DEHUMID MODE CLOSE W1

COMPRESSOR AND OUTDOOR FAN STOP; LSV AND DSV SOLENOIDS DE-ENERGIZED
8. OPEN W1 RESTORE UNIT TO DEHUMID MODE

9. OPEN HUMIDISTAT INPUT

COMPRESSOR AND OUTDOOR FAN STOP; LSV AND DSV SOLENOIDS DE-ENERGIZED
10. RESTORE SETPOINTS FOR THERMOSTAT AND HUMIDISTAT

REPEAT PROCESS FOR 2 COMPRESSOR SYSTEMS
© Carrier Corporation 2018
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53480177-01 Printed in U.S.A.
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Form 48HC-7-12-05SI Pg CL-2 4-18A 3-18 Replaces: 48HC-7-12-04SI