M03Q40G6-03 30/07/08
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CONTROL
The HEATING mode functions are active only on WSHH unit version .
In WSH units, the relative parameters are VISIBLE but NOT ACTIVE , for example the winter setpoint.
OPERING MODES
ON – OFF
Unit can be switched on and off by:
•
User keypad
•
remote or service keypad
•
remote switch (see ELECTRICAL CONNECTIONS paragraph)
•
Supervisor
COOLING
The compressor is activated with outlet temperature higher than set point
To switch from
cooling
to
heating
and vice versa, proceed as follows:
•
Turn the unit OFF
•
Wait until the plant water temperature (and external air) fall within the operating limits.
They can be switched over from the remote controls (refer to the ELECTRIC WIRING
paragraph).
HEATING
*
The compressor is activated with outlet temperature lower than set point
ECO
A secondary set-point can be used, with respect to the comfort setting
MAINTENANCE
the plant can be kept within the operating limits even when the unit is OFF or on STANDBY
SANITARY H2O
PRODUCTION
*
A specific set point is used, higher than the HEATING set ( see ELECTRICAL CONNECTIONS
paragraph ).
CHARACTERISTICS
THERMOREGULATION
The thermoregulation is based on the OUTLET temperature.
The unit is dimensioned for a determined TOTAL HEAD between input and output water temperature.
Usually the project step is 5°C; if the value is different, it is necessary reset parameters 37 and 38 (accessible to the service
centre).
In function of the total head, the installation determines the head quote that every resource (compressor, heating elements) is
able to provide: the STEP HEAD.
The control logic insert gradually the resources when the outlet temperature is higher than the set point + the head step.
The resources are activated one at a time and only at the SCAN TIME expiring.
The scan time is not fixed but it changes in function of the margin between the water outlet temperature and the Set point
value. Higher is the margin value (both in positive and in negative) shorter will be the space among the scan points.
The scan time value is visualized at status 4; when the status 3 has reached the status 4 value, the compressor operating
request is activated.
What above described, refer to the COOLING operating; in HEATING the logic is the same but “overturned” (compressor
insertion for outlet temp. < set-point –step head).
OUTLET temperature
head step
ACTUAL set point
OUTLET temperature SURVEY,
at SCAN TIME expiring
time
VARIABLE scan time
* only WSHH
