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AVMFE18LJ1101 - 6795746_02
the Heating set point by a value equal
to the dead band, there is an automatic
swap to Cooling operation.
If the actual ambient temperature falls
below the Cooling set point by a value
equal to the dead band, there is an
automatic swap to Heating operation.
Heater switch-on and switch-off depends
solely on the thermostat operation
request.
In this case, a fixed correction of the
ambient probe is envisaged, and is
determined on the basis of the type of
thermostat configured.
• Behaviour with a faulty ambient
temperature probe
-
2-pipe system:
With the selector in the OFF/Aux
position, ventilation switched off and
the valve is closed.
With the selector in the AUTO, V1,
V2, V3 position, the Heating mode is
fixed and the valve is always open.
The ventilation makes on-off cycles
of variable duration depending on the
position of the temperature selector.
- 4-pipe system:
With the selector in the OFF/Aux
position, ventilation switched off and
the valve is closed
With the selector in the AUTO, V1, V2,
V3 position, the Heating/Cooling mode
is decided on the basis of the position
of the temperature selector, activating
the respective valve. The ventilation
makes on-off cycles of variable duration
depending on the position of the
temperature selector.
• Behaviour with a faulty ambient
temperature probe on a Slave fan coil
The board automatically assumes the
reading of the ambient probe of the
Master fan coil.
• Heating mode with electric heater
(if present)
The electric heater must be enabled by
configuring the dip-switches on the
thermostat again. Activate the heater-
operated heating by positioning the
control panel selector on AUX.
Standard operation is of the ON-OFF
type.
The electric heater intervenes when there
is a thermostat operation request and
the water temperature is sufficiently
low.
It should be noted that when the
thermostat starts up, the heater is OFF,
so it will only be activated if the water
temperature is below the enabling
threshold (35°C with normal band and
31°C with reduced band).
In any case, the activation of the electric
heater involves a similar ventilation
management to that in Automatic mode.
If the fan coil is operated with continuous
ventilation, then the electric heater will
switch off when the set point is reached.
Following the post-ventilation phase
(described below), ventilation continues
at speed Vmin (Vmin can be selected
using Dip.8).
Electric heater operation involves
pre-ventilation and post-ventilation
phases in relation to its activation and
deactivation.
It should be noted that the pre-ventilation
phase (20” at Vmin) always corresponds
to the activation of the electric heater,
while the post-ventilation phase always
corresponds to the deactivation of the
electric heater (60” at Vmin).
Example: the thermostat requests fan
operation with the heater activated (i.e.
the water temperature is sufficiently
low), so we will have 20” of ventilation
at speed Vmin (pre-ventilation) after
which the thermostat will operate at
the ventilation speed determined by
the microprocessor on the basis of the
difference between the actual ambient
temperature and the set temperature.
Once the set temperature has been
reached, if the heater is still active (i.e.
the water temperature is sufficiently
low), we will have post-ventilation for
1min at speed Vmin.
It should be noted that when the heater is
switched off during operation because
the water temperature is sufficiently high,
then after reaching the set temperature,
ventilation continues at speed Vmin for
the remaining time needed to terminate
the post-ventilation cycle.
Finally, please note that the heater is
never enabled if the thermostat is in
anti-freeze or emergency mode, due to
the ambient probe.
• Operation with purifying devices (if
present)
If purifying devices are installed
(Plasmacluster or bactericidal lamp),
they must be enabled by configuring the
dip-switches on the thermostat again.
With the selector on “Aux”, the ambient
is purified regardless of the thermostat
operation requests.
Unlike the electric heater however, this
type of accessory is even activated
if the operation speed selector is not
positioned on “Aux”.
On “Aux”, the fan will always operate
at minimum speed, closing any shutoff
element whose use is recommended
with this function and thereby avoiding
any ambient alterations (overheating /
under-cooling).
