Thermo King 098203, Maintenance Manual

Page: 234 / 264

Diagnosis: Troubleshooting, Warnings and Alarm Codes
232
15 Evaporator Fan Low Speed Current Too Low
• Occurs during pretrip (PTI) or function test only.
• Fan power consumption is 33% below expected
current draw or phase current level differs 33% or
more.
• If both alarm #14 and #15 is active this indicates
too high phase difference.
• Expected fan current is a function of the power line
frequency and the supply voltage.
• With 20’ setting below approximately
- 0,5Amp@400VAC/50Hz
- 0,6Amp@460VAC/60Hz
• With 40’ setting below approximately
- 0,5Amp@400VAC/50Hz
- 0,6Amp@460VAC/60Hz
• Indicates:
• Defective or open fan motor internal over
temperature protection switch.
• Incorrect motor or motor connections.
• Defective volt or amp meter on power module.
• Open evaporator door and make sure all fans
rotate freely.
• Enter Manual Function Test and start
evaporator fans on low speed. Make sure all
fans start on low speed. If a motor does not
start and is very hot, wait 10 minutes for
internal over temperature switch to close.
• Enter Manual Function Test and start
evaporator fans on high speed. Make sure all
fans start on high speed. Check fan motor
volts and amps.
• With 20’ setting expect
- 0,8Amp@400VAC/50Hz
- 0,9Amp@460VAC/60Hz
• With 40’ setting expect
- 0,8Amp@400VAC/50Hz
- 0,9Amp@460VAC/60Hz
16 Condenser Fan Current Too High
• Occurs during pretrip (PTI) or function test only.
• Fan power consumption is 33% above expected
current draw or phase current level differs 33% or
more.
• If both alarm #16 and #17 is active this indicates
too high phase difference.
• Expected fan current is a function of the power line
frequency and the supply voltage.
• Above approximately
- 1,5Amp@400VAC/50Hz
- 1,8Amp@460VAC/60Hz
• Indicates:
• Defective or stuck condenser fan motor.
• Incorrect motor or motor connections.
• Defective volt or amp meter on power module.
• Enter Manual Function Test and start
condenser fan. Make sure the fan starts.
• Check fan motor volts and amps.
• Expect
- 1,0Amp@400VAC/50Hz
- 1,2Amp@460VAC/60Hz
Alarm Codes, Descriptions and Corrective Actions (Continued)
Code Description Corrective Action