Samsung AM072BXV Series Service Manual page 262

Piping Diagram
7-3 Functions (cont.)
7-3-2 Control (cont.)
7-3-2-5 Protective control (cont.)
DSH (Discharge Super Heat) protection
▪ Purpose
Prevent liquid compression to protect the system and compressors.
▪ Concept
The compressor Suction Super Heat (SH) is raised to increase the DSH.
- DSH = Compressor discharge temp. – High pressure saturation temp.
- The compressor discharge temperature is defined during DSH protection control :
Min { Max(Tdis_comp1, Ttop_comp1), Max(Tdis_comp2, Ttop_comp2) }
▪ Control specifications in detail
- The target superheat changes to 6 K if the DSH is 10 K or lower.
DSH (K)
20
15
10
Samsung Electronics
Ph-Diagram
First heating release : the target SH is 3 K if in this state for 30 sec
Second heating release : SH release occurs 2 min after the first release
First cooling release : the target SH is 3 K if in this state for 30 sec
Second cooling release : SH release occurs 2 min after the first release if
Normal Operation
- If in this state for 30 sec,
∙ Cooling : Indoor unit EEV Target SH 6 K
∙ Heating : Main EEV Target SH 6 K
DSH increase
Af ter DSH protection
Befo re DSH protection
SH increase
Enthalpy
if the DSH is below 15 K
the DSH is above 10 K
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