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62-11637
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00054
DEFROST NOT COMPLETE
• ACTIVATION: Defrost cycle did not terminate automatically. (DTT and SAT did not reach termination tem-
perature of 55°F/12.8°C within 45 minutes or the SAT rose to 120°F/48.9°C during the cycle.)
• UNIT CONTROL: Alarm Only. While this alarm is active, the defrost timer will be temporarily set to initiate a
defrost cycle 1.5 hours of unit running time after the alarm comes on.
• RESET CONDITION: Auto Reset when defrost cycle is started again, or alarm may be manually reset via
keypad or by turning the unit off, then back on again.
NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, the active
alarm should clear itself (see reset condition above). Operate the unit through the appropriate modes to see if any
active alarm occurs. Continue with the steps below as necessary.
CORRECTIVE ACTIONS:
1.
Check Evaporator Fan Clutch
Check fan clutch operation in defrost. Must completely disengage fan.
2.
Check Refrigerant Charge
Refer to
3.
Check for Alarm 00018 (Low Refrigerant Pressure)
Check for Alarm
00018 LOW REFRIGERANT PRESSURE
. Alarm conditions must be corrected and
the alarm cleared to continue.
4.
Check DTT
a. Using a service (test) thermometer check temperature of evaporator tube sheet at DTT location and
compare with Unit Data. Must be within 2°F (1°C)
b. Check DTT and RAT wiring. Verify that RAT temperature is being displayed as RAT in unit Unit Data
and that DTT is being displayed as DTT. Correct wiring if required.
c. Check DTT and SAT resistance. 10K Ohms @ 77°F (25°C). Refer to
tances for different sensors.
d. Inspect DTT Should be fastened securely in place. Flat area of DTT must be against metal surface.
5.
Perform Pretrip Check
Run Pretrip & check for alarms. Any active alarms must be corrected and cleared before proceeding.
6.
Refer to Section 9.3.6 - Refrigeration System Not Heating
Refer to
Summary of Contents for Transicold X4 7300
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Page 119: ...62 11637 SECTION 6 MESSAGECENTER PARAGRAPH NUMBER Page 6 1 MESSAGECENTER MESSAGES 6 1 ...
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