Danfoss DSH Series Application Guide

System evaluation
HP and LP must be monitored to respect operating envelope limitation. We consider two types of operating
envelope management: Basic and Advanced.
Table 28: System evaluation
Basic
Advanced
• HP and LP switch
• MOP (Max Operating Pressure) ensured by expansion device
• Condensing pressure control
• DGT external setting points: R410A max 135°C (275°F), R454B/R452B max
150°C (302°F)
• HP and LP sensor
• Operating envelope limits integrated into control logic
• Temperature measurement (monitoring by sensor)
HP switch setting
CC-000166
Condensing pressure control
MOP < Max evap T°
LP switch setting
tests No1 and 2
DGT
Whole operating envelope limits integrated into control logic
CC-000192
Manage superheat
During normal operation, refrigerant enters the compressor as a superheated vapor. Liquid ood back occurs when
a part of the refrigerant entering the compressor is still in liquid state.
Liquid ood back can cause oil dilution and, in extreme situations lead to liquid slugging that can damage the
compressor.
Requirement
In steady state conditions the expansion device must ensure a suction superheat within 5K to 30K (9 to 54°F).
System evaluation
Use the table in relation with the application to quickly evaluate the potential tests to perform.
Table 29: System evaluation
Application
Tests to perform
Non reversible
Liquid
ood back test
Reversible
Liquid
ood back test
Defrost test
Scroll compressors, DSH090 to DSH600 | Application
© Danfoss | Climate Solutions | 2022.10 AB288965961751en-001402 | 48

Danfoss DSH Series Specifications

General

Brand	Danfoss
Model	DSH Series
Category	Air Compressor
Language	English