Thermo Scientific Jewett CTF306 Installation And Operation Manual page 11

Thermo Scientific Jewett CTF306 Blood Plasma Freezers
TROUBLESHOOTING SERVICE CHART
SYMPTOM POSSIBLE CAUSE
Compressor 1. Line disconnect switch open.
A will not start,
2. Fuse blown or breaker tripped.
no hum
3. Thermal overload tripped.
4. No cooling required
5. Control contacts stuck in open position.
6. Loose wiring.
7. Improper wiring
8. Liquid line solenoid valve will not open.
9. Motor electrical trouble.
10. Liquid line solenoid will not open.
Compressor 1. Low voltage to unit.
B
will not start,
2. Start capacitor failure or wrong.
hums but
3. Run capacitor failure or wrong.
trips on
4. Start relay failure or wrong.
thermal
overload. 5. Motor electrical trouble.
6. Internal mechanical trouble in
compressor.
7. Improper wiring
8. Excessively high discharge pressure.
Compressor 1. Low voltage to unit.
C starts, but
2. Run capacitor failure or wrong.
does not
3. Start capacitor failure or wrong.
switch off of
4. Start relay failure or wrong.
start winding.
5. Motor electrical trouble.
6. Internal mechanical trouble in
compressor.
7. Improper wiring.
8. Excessively high discharge pressure.
Installation and Operation
POSSIBLE CORRECTIVE STEP
1. Close disconnect switch
2. Check electrical circuits and motor
windings for shorts or grounds. Investigate
for possible overloading. Replace fuse or
reset breaker after fault
3. Overloads are automatically reset. Check
unit closely when compressor comes back on
line.
4. None. Wait until control calls for cooling.
5. Replace control.
6. Check all wiring junctions, tighten all
terminal screws.
7. Check wiring against diagram.
8. Repair or replace solenoid coil
9. Check motor for open windings, Short
circuit or burn out.
10. Repair or replace coil.
1. Determine reason and correct.
2. Replace start capacitor.
3. Replace run capacitor.
4. Replace start relay.
5. Check motor for open windings, Short
circuit or burn out.
6. Replace compressor.
7. Check wiring against diagram.
8. See high discharge pressure symptom.
1. Determine reason and correct.
2. Replace run capacitor.
3. Replace start capacitor.
4. Replace start relay.
5. Check motor for open windings, Short
circuit or burn out.
6. Replace compressor.
7. Check wiring against diagram.
8. See high discharge pressure symptom.
is corrected.
10