SYSTEMP – Installation Operation Manual (IOM SYSTEMP rev.N)

Table Of Contents
63
9.11 CHECKING THE REFRIGERANT LOAD AND COOLING CIRCUIT OPERATION
WARNING!
The compressor needs to be started up a few minutes prior to running the checks!
Correct plant operation, which depends on the choice of fundamental components and the dosage of the refrigerant load,
can be checked from the cooling circuit operating values.
A correctly-installed unit that operates within the limits provided in this manual, will present values according to the fol-
lowing table:
Operating values of cooling circuits
Evaporation pressure Between 8 BarG and 12 BarG
Evaporation temperature Between 4 °C and 15 °C
Suction temperature Between 10 °C and 21 °C
Overheating Stable at 6 K
Compression ratio Greater than 1,6
Discharge temperature Between 55 °C and 80 °C
Condensation pressure Between 20 BarG and 38 BarG
Condensation temperature Between 35 °C and 60 °C
Desuperheating Between 20 K and 30 K
Liquid temperature Between 25 °C and 50 °C
Sub-cooling Between 2 K and 10 K
EEV expansion valve opening Lower than 90%
For units with two cooling circuits, the operating values will be checked with both circuits running.
Values diering from those provided in the table can mean that there is an incorrect refrigerant charge or operating condi-
tions that do not comply with the limits set forth herein.
9.11.1 VERIFY THE REFRIGERANT CHARGE WITH THE DC INVERTER COMPRESSOR
During cooling capacity throttling stages, the operating values may appear satisfactory, however, they may no longer be
correct at higher compressor speeds.
It is therefore essential that the compressor works at maximum speed before proceeding with the verication of the oper-
ating values of the circuit.
WARNING!
Once the charging operations of the cooling circuit are complete, it is mandatory to log the
full amount of refrigerant introduced in the circuit on the CE marking found in the unit.