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00023 Low Refrigerant Pressure (continued)
4. Check High Voltage Components Amp Draw (with the unit operating)
a. Check condenser fan amp draw on all legs. (CDCON)
b. Check evaporator fan motor amp WARNING draw on all three legs (1EVCON)
c. Check compressor amp draw on all three legs. (CCON)
d. Check heater amp draw. (1HTCON1, 1HTCON2, 2HTCON1, 2HTCON2, 3HTCON1 and 3HTCON2 -
if applicable)
WARNING
!
Caution and good electrical practices must be used when working around and with high
voltage circuits.
Verify that all three actual amperage readings for each component are within 10% of each other, and
are within the values shown in Section 2.10.
5. Check Generator Voltage (If Used When Alarm Occurred) - Check voltage at GENCON L1-L2, L1-L3,
L2-L3. Must be within voltage limits shown in Section 2.10.
6. Check Power Source Voltage (If Used When Alarm Occurred) - Check voltage at PSCON L1-L2, L1-
L3, L2-L3. Must be within voltage limits shown in Section 2.10.
7. Check Voltage Output From Contactors
a. Check voltage at GENCON T1-T2, T1-T3, T2-T3. Must be within voltage limits shown in Section
2.10.
b. Check voltage at CCON with compressor operating. T1-T2, T1-T3, T2-T3. Must be within voltage
limits shown in Section 2.10.
8. Verify Accuracy of AC Current Sensor (CT1, CT2, and CT3)
a. Put microprocessor in PC mode. Refer to Section 5.3.2. Must have 0 AC1 Amps and 0 AC2 Amps in
Unit Data.
b. Use a clamp on ammeter to measure current draw of all three legs of the T side of GENCON. Meter
reading should be the same as Unit Data: Compare meter reading to Unit Data in PC mode.
Compare meter reading to Unit Data with unit under load.
9. Defective Overload Ground Fault (OGF) Detector - Opens prematurely. Remove and replace.
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