User manual

1592022700 User manual iCHILL 200CX Rel. 1.0 22/04/2009
33 DEFROST CYCLE
The defrost cycle starts only if all these steps are determined:
 Heat pump unit
 DF01≠0 (defrost enabled)
 The condenser/evaporator probe is configured (per circuit) (if the evaporator probe/s is/are defined, the defrost cycle is always
controlled by it / them).
33.1 FORCED DEFROST
The function is enabled if the parameter dF19<>0. It allows to make a forced defrost cycle even if the dF09 timeout counting is not
expired, when the condensing/evaporating temperature/pressure is lower than dF20 setpoint for the dF19 time counting.
If during the dF19 time counting the condensing/evaporating temperature/pressure rises above the value dF20+dF21 (set+differential)
the function is disabled and the dF19 time is reloaded.
ATTENTION: the forced defrost is not related to the dF09 /dF06 delay times, therefore the forced defrost cycle, if condition are OK, is
immediately executed.
33.2 COMBINED DEFROST
The function is enabled if one of the digital input is configured as NTC temperature for combined defrost of the 1
st
or 2
nd
circuit. This
probe detects the external air temperature of the condenser (evaporator in heat pump) and determines the start and the stop of the
defrost cycle.
Description of the functioning:
The count-down to the defrost cycle starts when the temperature/pressure of the probe, configured as condensing/evaporating circuit 1
or 2 probe, is lower than dF02 parameter.
After the dF09 counting the instruments checks the temperature probe value (configured as combined defrost circuit 1 or 2) and if it is
lower than dF10 (temperature setpoint to start the defrost of the circuit1) or dF12 (temperature setpoint to start the defrost of the
circuit2) the defrost cycle starts otherwise the unit still runs in heat pump mode.
When the temperature decreases under the dF10 or dF12 values the defrost immediately start.
The defrost ends when the NTC combined defrost probe 1 or 2 increases over dF11 (circuit1) or dF13(circuit2).
If the defrost is enabled the display allows to show the external temperature on the top display and the labels dEF1 (circuit1) or
dEF2(circuit2) on the bottom display aof the circuit read-out function.
33.3 MANUAL DEFROST
The manual defrost key function is enabled if the unit is on with at least one compressor running.
The defrost start temperature/pressure of the controlled probe must be lower than dF02 setpoint value while if the combined defrost is
active the detected temperature must be lower than dF10 or dF12.
At this point by pushing SET + UP for more than 5 seconds the manual defrost starts.
ATTENTION: the manual defrost is not related to the dF09 /dF06 delay times, therefore the forced defrost cycle, if condition are OK,
is immediately executed for both circuits.
33.4 DEFROST START CONDITION WITH TWO CIRCUIT UNIT
Parameter involved: dF22
0= Independent
1= Only if both circuit conditions are satisfied
2= At least one circuit condition is satisfied
33.5 START/STOP DEFROST IN A TWO CIRCUITS UNIT WITH ONE CONDENSING FAN CONTROL UNIT
The table below shows the possible configuration of the parameters dF22 and dF23.
Parameter dF23=0 dF23=1 dF23=2
dF22=0 not possible (ACF1) not possible (ACF1) not possible (ACF1)
dF22=1 not possible (ACF1) Yes Yes
dF22=2 not possible (ACF1) Yes not possible (ACF1)
ATTENTION:
The configuration error ACF1 is displayed if the parameter value of dF22 and dF23 is not permitted.
33.6 START/STOP DEFROST IN A TWO CIRCUITS UNIT WITH TWO CONDENSING FAN CONTROL
UNIT
The table below shows the possible configuration of the parameters dF22 and dF23.
Parameter dF23=0 dF23=1 dF23=2