5
System deactivation by means of magnetic switch
It is also possible to force temperature control exclusion via the use of a magnetic window
switch connected to the relevant terminals. This helps to avoid wasted energy. The activa-
tion of this mode is indicated on the display by the word
.
Frost Protection Control
Whenever temperature control on the TA450 is bypassed, either manually or automatically,
differential FROST protection remains active thus safeguarding both the boiler and the water
pipes. The FROST PROTECTION temperature is programmable from +3°C to +16°C.
+3°C
–3°C
Temperature measurement calibration
Should the positioning of the TA450 not prove to be ideal (for example when situated close
to a heat source) temperature measurement can be inaccurate: to overcome this problem
the reading can be calibrated by +/– 3°C thus optimising comfort and energy consumption.
Thermal differential control
This control system is recommended for installations that are particularly difficult to control
such as those that experience extreme variations in external temperature. It guarantees
maximum benefit from the installation with minimum consumption. In order to adapt the
system to installations that feature differing thermal inertias (convector heaters, underfloor
heating, electric heaters) the temperature differential can be set between 0°C and 0 9°C
PI
Proportional/Integral Control
Allows for the optimisation of fuel consumption while enjoying the maximum of environ-
mental comfort by reducing the number of times the boiler is ignited as a function of the
difference between the set temperature and room temperature: the smaller the difference
between the two temperatures the fewer the number of times the boiler is ignited thus
leading to a considerable reduction in energy consumption while maintaining a certain
degree of comfort. The TA450 allows for the selection from among three preset programmes
depending on the type of system to control (P1, P2 and P3). Alternatively programme P4,
which is completely manual, can also be selected (See table 1 on page 18).
Integral proportional adjustment has the advantage of permitting the management of a
wider variety of systems with respect to the setting of the thermal differential. It is especially
suitable for underfloor and radiant systems. The difference between the set temperature
and the ambient temperature is just a few tenths of a degree. This allows for more precise
adjustment.
Temperature Set-point Adjustment Blocking
The TA450 can block the programming of temperature set-points thus avoiding accidental
changes to settings. Using this feature the user is free to select one of three pre-pro-
grammed levels without the possibility to change them.
