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Type B Electronic Control
GB - 4
Control
ON
1 2 3 4 5
OFF
Seasonal changeover button
This button allows selecting the operating mode, cooling, heating or
automatic.
Energy saving button
This button activates the energy saving function which modi
fi
es room
temperature as follows: in heating, the selected temperature is redu-
ced by 4°C; in cooling, the selected temperature is raised by 4°C.
Light indicators
Blue LED
ON
cooling
mode
(
).
Flashing
frost protection
mode
(
)
.
Red LED
ON
heating
mode
(
).
Flashing
Presence of a fault
(sensor failed or not connected).
Yellow LED (A)
ON
automatic
mode
(A).
Blue LED + Yellow LED
Both ON
automatic
mode
(A) - cooling (
)
.
Red LED + Yellow LED
Both ON
automatic
mode
(A) - heating (
)
.
Yellow LED ( )
ON
energy saving
mode
.
Flashing
External contact is open.
Red / Blue LED
Flashing
“Autotest”
mode.
Dip-switch functions (Microswitch)
Dip-switch No. 1
When
ON
permits enabling the frost protection (
) function.
Dip-switch No. 2
When
ON
permits fan operation at the selected speed even if the
set point is satis
fi
ed.
Dip-switch No. 3
When
ON
restricts the range of temperature selection, according to
the following limits:
Cooling:
minimum selectable temperature: 23°C.
Heating:
maximum selectable temperature: 21°C.
Dip-switch No. 4
When
ON
periodically activates the fan even if the set point is sati-
s
fi
ed (air sampling).
Dip-switch No. 5
When
ON
permits enabling the Booster Heating function (additio-
nal heating)
Dip-Switch confi gurations (Microswitch)
Dip-switch 1
OFF
Frost protection (
) disabled.
ON
Frost protection (
) enabled.
Dip-switch 2
OFF
Ventilation controlled by thermostat.
ON
Continuous ventilation.
Fig. 8
Internal temperature sensor
Dip-switch selector
Dip-switch 3
OFF
Temperature block disabled.
ON
Temperature block enabled.
Dip-switch 4
OFF
Air sampling disabled.
ON
“Air sampling enabled.
Dip-switch 5
OFF
“Booster Heating” disattivato
.
ON
“Booster Heating” attivato
.
NOTE:
Factory setting is with all dip-switches in the OFF position.
Diagnostic warnings
The following alarm situations are indicated:
Defective sensors: the red LED fl ashes.
Possible causes:
• failure or short circuit of internal sensor;
• failure or short circuit of water temperature sensor.
Incorrect confi guration
The yellow LED fl ashes every 0.25 seconds.
This happens when:
• in control, both centralised seasonal changeover signals “RC and
RH” are enabled.
Autotest
The autotest function is activated by holding the seasonal changeo-
ver button pressed and at the same time pressing the “ ” button
three times within 1 second. In this way it is possible to check the
starting of all fan coils.
The blue and red LEDs will begin to
fl
ash.
Each of the various units will be activated for 10 seconds in the
following sequence:
Low
fan
speed.
Medium fan speed.
High fan speed.
CV
Motorized cold-water valve.
HV
Motorized hot-water valve.