Technical data

Ichill 200CX EVO rev 1.1 14/11/2013
Pag. 87 of 151
FS36 Free cooling maximum time
0 250 min
FS37 Set point Free cooling
-50.0
-58
0.0
0
70.0
158
50.0
725
°C
°F
bar
psi
FS38 Proportional band Free coling
0.1
0
0.1
1
25.0
45
14.0
203
°C
°F
Bar
Psi
FS39 Minimum value Free cooling analog output
0 100 %
FS40 Maximum value Free cooling analog output
0 100 %
FS41 T1 probe selection for Free cooling
0=disabled, 1=Pb1, 2=Pb2, etc.
0 10
FS42 T2 probe selection for Free cooling
0=disabled, 1=Pb1, 2=Pb2, etc.
0 10
FS43 Outside temperature set point to force the maximum speed of
condenser fan
0 1
• Only free cooling for cooling (CF77=2)
Compressors are not used for cooling.
Evaporator and condenser water pumps are managed according to chiller probe and St01 set point;
free cooling valve/pump is managed according chiller probe and FS37 set point (or St01 if
St01<FS37).
If the free cooling set point is not reached in FS36 minutes (0 = function disabled) or when the free
cooling set point is reached, the free cooling will be disabled for FS34 minutes.
After this time the valve/pump is switched on for FS35 seconds and, when this time is elapsed the
controller verify if T1 temperature – T2 temperature ≥ FS21 and if free cooling temperature > FS37.
If both condition are true, the free cooling valve/pump is activated.
If FS34=0 and FS35=0 this function is disabled.
• Compressors and free cooling used for cooling (CF77=2)
Compressors are managed as standard chiller regulation.
Free cooling valve/pump is managed according chiller probe and FS37 set point (FS37 has to be set
>St01); the regulation is done like figure above.
Low temperature protection
If the temperature detected by probe selected with FS62 parameter is lower than FS63 set point, the free
cooling is disabled.
The free cooling will be enabled when temperature detected by probe selected with FS62 parameter is
higher than FS63 + FS64.
43.1 FAN SPEED CONTROL IF COMPRESSORS AND FREE COOLING ARE USED
FOR COOLING (CF77=3)
When the free cooling is not active the condenser fan speed is managed like standard regulation.
If free cooling is active:
• outside temperature > FS43 + FS44: condenser fan speed is forced at maximum speed
• outside temperature < FS43: when outside temperature decreases below FS43 temperature, after
FS45 minutes the condenser fan speed is managed as standard regulation