11-8
CONTROL SYSTEM
SM TRIO52 1-A.2 GB
11.17.4 Compressor over Current Protection
Normal
Stop-Rise
HzDown1
HzDown2
Stop-Compresor
CCROC1
CCROC2
CCROC3
CCROC4
CCR
11.17.5 Outdoor Coil Deicing Protection
11.17.5.1 Deicing Starting Conditions
Deicing operation will start when either one of the following conditions exist:
Case 1: OCT < OAT – 8 AND TLD > DI
Case 2: OCT < OAT – 12 AND TLD > 30 minutes.
Case 3: OCT is Invalid AND TLD > DI
Case 4: Unit is just switched to STBY AND OCT < OAT – 8
Case 5: NLOAD = 0 AND OCT < OAT -8
OCT – Outdoor Coil Temperature
TLD – Time from Last Deicing
DI – Deicing Interval (Time Interval Between Two Deicing)
Deicing interval time when compressor is first started in heat mode, is 10 minutes if OCT < -
2, and is 40 minutes in other cases.
Deicing interval time is changed (increased/ decreased in 10 minutes steps) as a function of
deicing time. If deicing time is shorter then former deicing time, the deicing interval time will
be increased. If deicing time is longer then former deicing time, the deicing interval time will
be decreased.
CONTENTS