Sanden
Heat
Pump
–
Service
Technical
Book
Page
8
of
48
Defrost
Start of defrost is determined by the temperatures detected by Defrost TH and
Inlet Air TH. If the condition meets one of the determination values, HP unit starts
defrost drive. However, the defrost drive is cancelled for 12min after the
compressor runs or 30min after defrost drive completes. Also, if GC Inlet TH >
32
o
C, defrost drive does not start.
End of defrost is determined either by the temperature detected by Defrost TH or
by the time passed after start. Defrost drive stops when the condition meets one
of the determination values.
Times of Retries at Error Occurrence
Number of times to retry recovery when an error is detected is increased from 5 times
to 7 times as a countermeasure for the electrical testing.