REXNOVA ISA 20 BITHERMAL, Installation, Use And Maintenance Manual

Page: 6 / 36

4
INTERFACE DESCRIPTION
SEASON SELECTION
TURNING THE BOILER ON
Turn on the boiler’s electrical supply by the
switch, which must be installed on the power
supply line to the boiler. The LCD display (will
turn on immediately, showing all the available
symbols for 5 seconds, and the program
version installed in the microprocessor for
further 5 seconds; the unit goes into stand-by
and the display shows the word “OFF”.
By pushing the “E” button, the boiler goes
into “ON” mode; the display shows CH circuit
temperature and the “TAP” symbol, thus
indicating the summer mode (Pict. 4).
The boiler has now been started and ready
to operate.
The boiler has three operating modes,
which depend on the active functions,
in response to the external temperature
or the user requirements:
The SUMMER mode can be set,
during which all the CH functions
are deactivated and the domestic
hot water production mode only is
maintained: this mode is selected by
pushing “E” button and then the “TAP”
symbol (Pict.4) is displayed; when
the unit is in stand-by, the CH circuit
temperature is shown on the display
TURNING THE BOILER OFF
Pushing several times the “E” button until the
word “OFF” is displayed.
(Pict. 4): during an intake of DHW water,
the DHW temperature is shown together
with the flashing “TAP” symbol and
with the “FLAME” symbol of the ignited
burner.
The WINTER mode is activated by
pushing “E” button and then the “TAP”
and “RADIATOR” symbols (Pict.5) are
displayed. In this mode, the unit satisfies
both DHW requests, and CH requests.
When the unit is in stand-by, the CH
circuit temperature is shown on the
Pict. 3
Pict. 3.1
WARNING: In this mode the
boiler is inactive but its electricity
supply is still connected!
A
B E F D
C
A. DHW TEMPERATURE INCREASE
B. DHW TEMPERATURE DECREASE
C. CH TEMPERATURE INCREASE
D. CH TEMPERATURE DECREASE
E. FUNCTION SELECTION
F. RESET BUTTON