Installation manual
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no control on the boiler functions which depend on the control panel commands. If the
boiler has to operate at low temperatures and has remote control, simply select the
required temperature directly on the remote control unit.
When operating with the remote control without other thermostats (single zone system)
jumpering must not be used on the room thermostat wires.
2.8 Automatic high/low temperature circuit
The boiler has an automatic function which has been developed to optimise performance
in systems that have circuits with different temperatures.
In circuits with two different temperatures, normally one for the radiator zone and one for
the radiant heating panels, the boiler operates at the higher temperature if there is a
simultaneous request from both circuits and at the temperature for the radiant heating
panels (lower temperature) if the request comes from the lower temperature circuit only.
Operating is controlled by two room thermostats, one for the high temperature zone
(25÷85°C) and one for the low temperature zone (25÷45°C) which must be connected to
the two dedicated wires that come out of the control panel and are specifically labelled.
The situation is summarised in the table below.
High TA
state
Low TA
state
Boiler operating
temperature °C
Boiler pump
OFF OFF OFF OFF
ON
OFF
25
÷
85°C
ON
OFF
ON
25
÷
45°C
ON
ON ON
25÷85°C
ON
However, this automatic function does not mean that the boiler can directly supply a low
temperature zone and a high temperature zone without the help of a mixer circuit.
N.B.: a mixing system like the SILE TBA/TBA-M must be installed on mixed
circuits and a safety device must also be installed on the low temperature
circuit, i.e. a safety thermostat set at 50°C on the delivery pipe downstream
of the mixed circuit.
On systems with only one operating temperature, the room thermostat that is not required
must be left open.
E.g.:
a)
if a radiator system has to be supplied, the room thermostat must be connected to
the wire which receives input from the high temperature zone and the one for the
low temperature zone must be left open (factory setting).
b)
if a low temperature circuit has to be supplied, the room thermostat must be
connected to the wire which receives input from the low temperature zone and the
one for the high temperature zone must be left open.