
19
GENERAL
F1
E1
H1
A1
F
C1
D1
B1
G1
I1
L1
A1
Functioning mode.
Press the
M
key to activate the various modes, as shown by the line under the
corresponding symbol.
B1
DHW mode.
Press the
V
key to activate and deactivate DHW mode.
C1 Daytime
CH mode
D1
Time of day
E1
Current boiler temperature
F1
Water pressure (not used)
G1
Flame detected
H1
Current time bar
I1
CH mode active
L1
DHW mode active
MAIN SCREEN
Notes on functioning
The control panel on the
TAU UNIT
boiler controls the following functions:
− The DHW priority function. This ensures that the
boiler can still serve the central heating circuit
even when domestic hot water is drawn off.
− The frost protection function.
This stops water freezing inside the boiler. If
boiler temperature falls below 5°C, the burner
ignites and runs at full power until temperature
reaches 10°C.
The frost protection function is only active if
an outdoor temperature sensor is connected.
If outside temperature drops below -5°C the
pumps are switched on. If outside temperature
is between -4° and 1.5°C, the pumps are
switched on for 10 minutes at intervals of 6
hours. If outside temperature is above 1.5°C the
pumps are switched off.
− Overtemperature dispersal function. If the tem-
perature threshold thermostat trips (86°C) the
boiler shuts down and accumulated heat is di-
spersed by switching on the central heating
pump. If boiler temperature rises to 89°C, the fan
is switched on too.
− The cascade control function. The addition of a
controller (accessory) allows you to connect a
number of boilers in cascade, sharing heat ou-
tput between a number of burners and impro-
ving overall system efficiency.
− Boiler switching differential. This establishes a
minimum off time for the burner, to stop it igni-
ting and shutting down repeatedly. The boiler
will only start up again if the difference between
the setpoint and the actual boiler temperature
exceeds a predetermined value.