Troubleshooting - Thermo Scientific XBF40-MD Series Installation, Operation And Service Manual

14.3 Troubleshooting

Table 2: Troubleshooting Procedures
SYMPTOM
Cabinet temperature colder
than Control Setpoint
Displayed temperature does not
match freezer temperature.
Frost build-up on breaker strip
Thermo Scientific XBF40-MD Series Blast Freezers
CAUTION: Only certified Refrigeration or Electronic Technicians should
service the system.
Note Before attempting to troubleshoot the unit, perform the following checks.
Correct what is found wrong and re-evaluate the unit before continuing.
Before troubleshooting, verify that the main power is supplied to the freezer.
POSSIBLE CAUSE
1. Control programmed incorrectly.
2. Inoperative control.
3. Temperature sensor defective.
1. Needs calibration.
2. Defective sensor.
1. Gasket not sealing properly.
2. Door latch may need adjustment.
TEST AND CORRECTION
1. Reprogram.
2. Measure voltage
controller on Pins 1 & 3, Replace
control if necessary.
3. Replace sensor
1. Recalibrate controller as specified
in procedure.
2. Replace
1. Gasket wrinkled, worn or torn.
Check retaining means and replace
if necessary. Frost will accumulate
at the point of an air leak. Check
carefully in the area of any
concentrated frost build-up.
2. Check door latch and adjust for
proper door adjustment.
Installation, Operation and Service Manual
Appendix
on back of
33