!
USER MANUAL – Release 1.2 of 01/01/2010
Page 121 of 191
Version: 02/03/2010
45.3 UNLOADING BY LOW PRESSURE TRANSDUCER
The low pressure unloading function is only active with unit working in heating mode.
The function is managed by means of the analogue input configured as circuit evaporation pressure probe
FUNCTION ACTIVATED:
If the pressure measured by the evaporation probe is equal to or exceeds the set for a time that can be set,
the unloading function of the circuit to which the probe belongs is activated. The power available is managed
via the parameter chosen of the steps to be inserted into the circuit.
FUNCTION DEACTIVATED:
When the pressure measured is less than or equal to the Set - Diff. The unloading function is deactivated or
however, to prevent prolonged working in unloading with pressure conditions between activation set and
deactivation differential, when the evaporation pressure is below the set, the time set is counted. When this
has expired the function is deactivated even if the pressure has not dropped below the set-differential.
45.4 UNLOADING DUE TO EVAPORATOR WATER INLET HIGH TEMPERATURE
Manages the unloading due to unit inlet water. The function is always active and enabled in any working
mode with at least 2 power steps in a circuit.
Used to allow the unit to function (via -partialisation of the compressors) also with evaporator water inlet high
temperatures (start-ups in summer with very hot storage tank), and to prevent a possible high pressure
intervention.
The unloading function is managed via the analogue input configured as NTC probe selected in the relevant
parameter.
FUNCTION ACTIVATED:
If the temperature measured by the probe is the same as or exceeds the SET for a time that can be set, all
active circuits are put in Unloading mode. The power available is managed via the parameter selected of the
steps to be inserted into the circuit.
FUNCTION DEACTIVATED:
When the temperature measured is <= SET- DIFF, the function is deactivated. However to prevent
prolonged working in unloading mode, if the temperature is between SET- DIFF and SET (when the
temperature drops below the SET), a time is counted on the expiry of which the function is deactivated.
45.5 EVAPORATOR WATER LOW TEMPERATURE UNLOADING (NO AIR-AIR)
Used to allow the unit to function (via partialisation of the compressors) also with evaporator outlet water low
temperatures to prevent a possible anti-freeze intervention.
