Thermo King 098916, Руководство по обслуживанию

Страница: 166 / 196

Diagnosis: Troubleshooting, Status Messages, Alarm Codes
165
24 Supply Air Temperature Too Low
(Check Alarm)
• During Chill or Frozen Mode: Supply air
temperature is too low compared to return air
temperature under operating conditions.
• Indicates:
• Ice or frost on evaporator coil
• Low heating capacity
• Incorrect evaporator fan operation
• Incorrect connection or location of supply or
return air sensors
• Check for sensor or evaporator fan alarm codes.
• Open evaporator door. Inspect coil for ice or frost
and initiate manual defrost if necessary. Check
for correct evaporator fan motor rotation and
operation.
• Check supply and return sensor connections
and locations.
25 Return Air Temperature Too High
(Check Alarm)
• During Defrost: Return air temperature
increases above 40 C (104 F).
• Indicates:
• Defective return or evaporator coil sensor
• Return and evaporator coil sensor
connections are reversed
• Check for sensor alarm codes.
• Check supply and return sensor connections
and locations.
26 Evaporator Coil Temperature Too High
(Check Alarm)
• During Chill or Frozen Mode: Evaporator coil
temperature is too high compared to return air
temperature under operating conditions.
• Indicates:
• Low refrigerant charge.
• Defective evaporator coil or return air
sensor
• Incorrect connection or location of
evaporator coil or return air sensor
• Check for sensor alarm codes.
• Check discharge and suction pressure gauge
readings and check refrigerant charge.
• Check evaporator coil and return air sensor
connections and locations.
27 Evaporator Coil Temperature Too Low
(Check Alarm)
• During Chill or Frozen Mode: Evaporator coil
temperature is too low compared to return air
temperature under actual operating
conditions.
• Controller initiates defrost if no recent defrost.
• Indicates:
• Airflow is blocked in the container
• Evaporator fans do not operate
• Fresh air exchange vent open too much on
frozen load
• Defective evaporator coil or return air
sensor
• Check for sensor or evaporator fan alarm codes.
• Open evaporator door. Inspect coil for ice or frost
and initiate manual defrost if necessary. Check
for correct evaporator fan rotation and operation.
• Inspect return air grille and cargo load. Remove
any debris or cargo from blocking return air
grille.
• At setpoints below 5 C (41 F), maximum air vent
setting is not allowed.
• Check evaporator coil and return air sensor
connections and locations.
Status Messages and Controller Actions (Continued)
Message
No.
Status Message Controller Action