T955_O: Compressor Temperature Thermistor Failure
On the VSODC, this fault will be indicated by the number 42
The Drive LED's will not indicate anything
The Compressor Thermistor is mounted under the compressor sound blanket and is attached to the compressor belly with a large wire tie. The compressor sump thermistor, as it is commonly referred to has been used to monitor compressor temperature for stator heat operation and floodback protection.
The system will run with this active alert and will show as a current fault. On older revisions of firmware, prior to revision 57, a failed compressor sump sensor would result in no stator heat to the compressor. This sensor should not be left disconnected.
In VSODC firmware revisions 42 and earlier, there was a chance in some markets that stator heat would block compressor operation. Many technicians removed the sensor and lived with the alert. Later revisions used different criteria for stator heat. If this sensor is failed (open or shorted), replace the sensor. Be sure to strap it to the compressor about 4" up from the base of the compressor."
