Gattetti LCA User Manual page 23

correspond to the real tension applied, but to an internal variable within the µchiller. See page 60 to find the value of F4.
If either the ON/OFF converter (code CONV0NOFF0) or the PWM/0÷10V converter (code CONV0/10A0) are used we
recommend to set this parameter to its maximum value (166 in case of mains frequency of 50 Hz, 138 if it is equal to
60Hz) and close the jumpers P1 and P6 located in the single compressor board and in the expansion for control of the
second compressor.
F5: Temperature/pressure for minimum "Summer" speed (cooling mode).
It indicates the temperature or pressure below which the fans are activated at minimum speed. In ON/OFF regulation
models, this parameter indicates the temperature or pressure below which the fans are stopped.
F6: Temperature/pressure for maximum "Summer" speed (cooling mode)
It indicates the temperature or pressure above which the fans must be activated at maximum speed. In models with
ON/OFF regulation, this parameter indicates the temperature or pressure above which the fans are actuated.
F7: Temperature/pressure for minimum "Winter" speed (heating mode)
It indicates the temperature or pressure above which the fans are activated at minimum speed. In ON/OFF regulation
models, this parameter indicates the temperature or pressure above which the fans are stopped.
F8:Temperature/pressure for maximum "Winter" speed (heating mode)
It indicates the temperature or pressure below which the fans must be activated at maximum speed. In with ON/OFF
regulation models, this parameter indicates the temperature or pressure below which the fans are actuated.
F9: Temperature/pressure at which the fans turn OFF (Cooling mode)
If the system includes a speed regulator to control the fans, this parameter allows to set the temperature or pressure
below which the fans are turned OFF. For Cooling activation there is a post-differential with respect to the set point of
1°C when using NTC probes (B3 and B5) and of 0.5Bar, when using pressure probes.
FA: Temperature/pressure at which the fans turn OFF (Heating mode)
If the system includes a speed regulator to control the fans, this parameter allows to set the temperature or pressure
above which the fans are turned OFF in order to avoid overload for the compressor due to high evaporating
temperatures.. For Heating activation there is a pre-differential with respect to the set point of 1°C when using NTC
probes for the control of condensation (B3 and B5) and of 0.5Bar when using pressure probes.
Fb: Fans starting time
It allows to set the max. speed of the fans during starting, in order to overcome the mechanical inertia of the motor. If
Fb=0 this function is ignored, that is the fans are activated at the minimum speed and then controlled according to the
condensing temperature/pressure. The same timing is respected when the compressor is turned on (independently of the
condenser temperature/ pressure), if the NTC probes for the control of condensation have been selected and the speed
regulation has been enabled (F2=2), so as to prevent the sudden increase in pressure (that does not necessary
correspond to an increasing of the temperature in the place where the probe is located) and improve the control action.
Defrosting (parameters "d")
d1: Defrosting ON / condensation antifreeze
For heat pumps with air condensation (H1=1, 3), it sets whether a defrosting control in the outdoor coil must be effected
(evaporator in Heating operating mode). With water/water heat pump with gas reversibility (H1=5), this parameter
indicates the control action against freezing effects in the heat exchanger used as evaporator in heating mode.
d2: Timed or temperature-based defrosting
It sets a timed defrosting (fixed time-interval) or a temperature-based cycle (defrosting will stop as soon as the
condensation probe reaches the end-defrosting temperature or pressure set by the USER or if the contacts for the end of
defrosting are detected open with dA=1).
d3: Temperature/pressure starting the defrosting cycle or condensation antifreeze alarm set point
With heat pumps with air condensation (H1=1, 3), it sets the temperature or pressure threshold under which a defrosting
cycle occurs. In order to activate a defrosting cycle such a condition must persist for a specific period of time (see
parameter d5). For water/water heat pump with gas reversibility (H1=5), this parameter defines the set point relative to
the antifreeze alarm in the heat exchanger used as evaporator in heating mode
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