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86
LEGEND
COMPRESSOR LOSES OIL
1. Leak in system.
1. Repair leak.
2. Crankcase heaters not energized during shutdown.
2. Check wiring and relays. Check heater and replace if defective.
FROSTED SUCTION LINE
Expansion valve admitting excess refrigerant.
Adjust expansion valve.
HOT LIQUID LINE
1. Shortage of refrigerant due to leak.
1. Repair leak and recharge.
2. Expansion valve opens too wide.
2. Adjust expansion valve.
FROSTED LIQUID LINE
Restricted filter drier.
Remove restriction or replace.
INDOOR FAN CONTACTOR OPEN
1. Power off.
1. Restore power.
2. Fuses blown in field power circuit.
2. After finding cause and correcting, replace with correct fuses.
3. No control power.
3. Check secondary fuses. Replace with correct type and size. Replace
transformer if primary windings are receiving power.
INDOOR FAN CONTACTOR CLOSED
1. VFD overload function tripped.
1. Refer to separate VFD technical manual for troubleshooting instructions.
2. Motor leads loose.
2. Check connections at motor lead junction box.
3. Motor windings open.
3. Check motor windings.
4. Single phasing.
4. Check for blown fuse. Check for loose connections at motor
junction box.
5. Belts broken or thrown.
5. Check belts. Replace as complete set if necessary.
6. Circuit breaker tripped.
6. Check for excessive current draw. Reset breaker. Replace if defective.
ASTP —
Advanced Scroll Temperature Protection
VFD
—
Variable Frequency Drive
Table 78 — Cooling Service Analysis (cont)
PROBLEM
SOLUTION
Summary of Contents for WEATHERMAKER 48A2020
Page 112: ...112 Fig 20 Typical Main Control Box Wiring Schematic 48 50A Units ...
Page 113: ...113 Fig 21 Typical Auxiliary Control Box Wiring Schematic ...
Page 114: ...114 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown ...
Page 115: ...115 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown TO NEXT PAGE ...
Page 116: ...116 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont ...
Page 117: ...117 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown ...
Page 118: ...118 Fig 25 Typical Controls Option Wiring Schematic SW1 SW2 OR DEHUMIDIFY SWITCH ...
Page 119: ...119 Fig 26 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown ...
Page 120: ...120 Fig 27 Typical Power Schematic of Greenspeed Low Ambient Option 48 50A 060 Unit Shown ...
Page 121: ...121 Fig 28 Typical Small Chassis Component Location Size 020 035 Units ...
Page 122: ...122 Fig 29 Typical Large Chassis Component Locations Size 040 060 Units ...
Page 185: ...185 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...