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Transducer Troubleshooting —
On 48/50AJ,AK,
AW,AY units, the electronic control uses 2 suction pressure
transducers to measure the suction pressure of circuits A and B.
The pressure/voltage characteristics of these transducers are in
shown in Tables 101 and 102. On 48/50A2,A3,A4,A5 units,
the electronic control uses 4 pressure transducers to measure
the suction and discharge pressure of circuits A and B. The
pressure/voltage characteristics of these transducers are shown
in Tables 103 and 104. The accuracy of these transducers can
be verified by connecting an accurate pressure gage to the sec-
ond refrigerant port in the suction line.
Table 94 — Cooling Service Analysis
LEGEND
PROBLEM
SOLUTION
COMPRESSOR DOES NOT RUN
Active Alarm
Check active alarms using local display.
Contactor Open
1. Power off.
1. Restore power.
2. Fuses blown in field power circuit.
2. After finding cause and correcting, replace with correct size fuse.
3. No control power.
3. Check secondary fuse(s); replace with correct type and size.
Replace transformer if primary windings receiving power.
4. Compressor circuit breaker tripped.
4. Check for excessive compressor current draw. Reset breaker;
replace if defective.
5. Safety device lockout circuit active.
5. Reset lockout circuit at circuit breaker.
6. High-pressure switch open.
6. Check for refrigerant overcharge, obstruction of outdoor airflow, air
in system or whether compressor discharge valve is fully open. Be
sure outdoor fans are operating correctly.
7. Loose electrical connections.
7. Tighten all connections.
Contactor Closed
1. Compressor leads loose.
1. Check connections.
2. Motor windings open.
2. See compressor service literature.
3. Single phasing.
3. Check for blown fuse. Check for loose connection at compressor
terminal.
4. ASTP activated (48/50A2,A3,A4,A5 only)
4. Allow 30 to 120 minutes for cool down. See Compressor Safeties
section on page 39.
COMPRESSOR STOPS ON HIGH PRESSURE
Outdoor Fan On
1. High-pressure switch faulty.
1. Replace switch.
2. Airflow restricted.
2. Remove obstruction.
3. Air recirculating.
3. Clear airflow area.
4. Noncondensables in system.
4. Purge and recharge as required.
5. Refrigerant overcharge.
5. Purge as required.
6. Line voltage incorrect.
6. Consult power company.
7. Refrigerant system restrictions.
7. Check or replace filter drier, expansion valve, etc. Check that
compressor discharge valve is fully open.
8. Fan running in reverse direction.
8. Correct wiring.
Outdoor Fan Off
1. Fan slips on shaft.
1. Tighten fan hub setscrews.
2. Motor not running.
2. Check power and capacitor.
3. Motor overload open.
3. Check overload rating. Check for fan blade obstruction.
4. Motor burned out.
4. Replace motor.
COMPRESSOR CYCLES ON LOW PRESSURE
Indoor-Air Fan Running
1. Filter drier plugged.
1. Replace filter drier.
2. Expansion valve power head defective.
2. Replace power head.
3. Low refrigerant charge.
3. Add charge.
4. Faulty pressure transducer.
4. Check that pressure transducer is connected and secured to suc-
tion line. If still not functioning, replace transducer.
Airflow Restricted
1. Coil iced up.
1. Check refrigerant charge.
2. Coil dirty.
2. Clean coil fins.
3. Air filters dirty.
3. Clean or replace filters.
4. Dampers closed.
4. Check damper operation and position.
Indoor-Air Fan Stopped
1. Electrical connections loose.
1. Tighten all connections.
2. Fan relay defective.
2. Replace relay.
3. Motor overload open.
3. Power supply.
4. Motor defective.
4. Replace motor.
5. Fan belt broken or slipping.
5. Replace or tighten belt.
ASTP —
Advanced Scroll Temperature Protection
VFD
—
Variable Frequency Drive
Содержание WEATHERMAKER 48/50AJ
Страница 103: ...103 Fig 15 Typical Main Control Box Wiring Schematic 48 50AJ AK AW AY Units cont a48 8355 ...
Страница 104: ...104 Fig 16 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units a48 8355 ...
Страница 105: ...105 TO NEXT PAGE Fig 17 Typical Auxiliary Control Box Wiring Schematic A48 7294 ...
Страница 106: ...106 Fig 17 Typical Auxiliary Control Box Wiring Schematic cont a48 8356 ...
Страница 107: ...107 Fig 18 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown a48 8357 ...
Страница 108: ...108 TO NEXT PAGE Fig 19 Typical Staged Gas Heat Wiring Schematic Size 051 and 060 Units Shown A48 7296 ...
Страница 109: ...109 Fig 19 Typical Staged Gas Heat Wiring Schematic Size 051 and 060 Units Shown cont A48 8358 ...
Страница 110: ...110 Fig 20 Typical Electric Heat Control Schematic 50 Series Size 051 and 060 Units Shown a50 8228 ...
Страница 111: ...111 TO NEXT PAGE Fig 21 Typical Power Schematic 48 50AJ AK AW AY051 and 060 Units Shown A48 7298 ...
Страница 112: ...112 FROM PREVIOUS PAGE Fig 21 Typical Power Schematic 48 50AJ AK AW AY051 and 060 Units Shown cont a48 8360 ...
Страница 113: ...113 Fig 22 Typical Power Schematic 48 50A2 A3 A4 A5060 Unit Shown ...
Страница 114: ...114 SW1 SW2 OR DEHUMIDIFY SWITCH Fig 23 Typical Controls Option Wiring Schematic a48 8361 ...
Страница 115: ...115 Fig 24 Typical Small Chassis Component Location Size 020 035 Units a48 8362 ...
Страница 116: ...116 Fig 25 Typical Large Chassis Component Locations Size 036 060 Units A48 7302 ...
Страница 169: ...169 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...