ENGLISH
IT
ALIANO
FRANÇAIS
DEUTSCH
LXTFF01M-IOM-1511
39
ECONOMY FUNCTION
The “Economy“ function allows to temporary set an energy saving
mode through a reduction of the actual setpoint temperature by a
step (con
fi
gurable) when in heating mode, or increasing it by the
same step when in cooling mode.
The value for this reduction step is set with parameter
P17
: when
this is set to 0.0 the Economy function is actually disabled. The
Economy mode is activated by the “ “ button, as described in
the “Description of controls” section.
The Economy mode can be remotely activated in centralised
mode, even for multiple thermostats, using the inputs to terminals
3 or 4 (see parameters
C14
and
C15
).
Since the thermostat is sensitive to signal status changes and
not to the level, use the “ “ button to change the activation
status of the Economy function, even when it is forced by the
centralised signal. When the Economy function is activated (“ “
icon on), fan speed is limited to the
fi
rst.
DIRTY FILTER WARNING FUNCTION
Fan-coils and other devices including a fan are often equipped
with a
fi
lter for the air in the suction path, which needs a periodical
maintenance and cleaning or replacement. This regulator can
warn the user when the maintenance has to be made, provided
the “Dirty
fi
lter warning“ function has been enabled.
The function is activated by setting the time-to-maintenance on
parameter
P24
. The thermostat will count the fan operation time
and when the threshold set in
P24
(per 100 hours) is reached,
the “
“
fi
lter icon blinks on the display. Once the
fi
lter has
been cleaned, to reset the warning and the time counter keep
the “ “ button pressed for 10 seconds, until the “
“
fi
lter icon
disappears from the display.
TEMPERATURE REGULATION
This device can drive in a proportional way both valves and fan in
order to control room temperature with the highest comfort and energy
saving. Nonetheless each different environment needs a different set
for some parameters in order to get an accurate regulation.
Parameters responsible for the regulation accuracy are:
- Proportional band:
C05
and
C06
- Integral time:
C07
and
C08
For each of the settings two parameters are available, because the
user is allowed to set different values for heating and cooling mode.
Proportional band, measured in °C, is intended as the difference
between setpoint and room temperature which is needed to fully
open the regulating valve.
The narrower the proportional band, the fastest is the regulator to
counteract temperature variations in the room. Yet a too “narrow“
value for this parameter can result in room temperature oscillations
or system instability.
A too “wide“value could result in the impossibility to reach the
setpoint temperature in the room. When the integral time is set to
zero, no integral action is made and therefore the regulation is purely
proportional (P type). When an integral time different from zero is
set the resulting regulation is made of a Proportional plus an Integral
action (P + I type).
The smaller the integral time, the greater the in
fl
uence of the integral
action and vice-versa: with a greater integral time the resulting
integral action is softer. A too soft or null integral action could result in
the impossibility to reach the setpoint temperature, meanwhile a too
strong integral action could possibly generate oscillations in the room
temperature. It is necessary to adjust these parameters according to
the actual environment in which the regulator is installed to get the
best regulation accuracy.
