Unical KUTter R 28, Installation And Servicing Manual

Page: 89 / 97

42
4.4 - IMPORTANT NOTEs
NOTE
The safety pressure switch against lack
of water does not give electric consent for
burner start when the pressure is below
0.4 bar.
The water pressure in the heating system
must not drop below 0.8/1 bar; open the
filling tap on the boiler when the pressure
is too low.
This operation must be performed with a
cooled system. The pressure gauge fitted
on the boiler allows you to read the circuit
pressure.
NOTE
If the boiler was without electric power,
after a certain idle period, the pump could
be blocked. Before electrically powering
the boiler, the pump must be unblocked
by operating as follows:
Remove the protective screw from the
pump centre using a cloth and insert a
screwdriver, manually turning the pump's
shaft clockwise. After having unblocked
the pump, tighten the protective screw
and make sure there is no water leakage.
ATTENTION!
After removing the protective screw, a
small amount of water could leak out. Dry
all wet surfaces before re-assembling the
casing.
4.4.1 - LEGIONELLA PROTECTION
FUNCTION
It is activated every 7 days (168 h) if temperature
of water contained into the tank has remained
permanentemenet below 61 °C, throughout the
(legionella) treatment period, the display shows:
VALUE
FROM TO sTANDARD
0 (OFF) 1 (ENABLE) 1 (ENABLE)
This function can be disabled by using REGOLA-
FACILE parameter TSP n. 24
NOTE
If preparation of the storage tank
is not enabled (
C in pos. 1
and
/ or Regolafacile in stand-by), at
the end of the counting (168 h)
the symbol is displayed on
the display, without switching on
boiler.
When the preparation of storage
tank is enabled ( c pos. 2 and /
or Regolafacile active), the boiler
switches to satisfy the request of
legionella protection).
The 168 h timer
stops counting
and reset if the storage water
temperature exceeds 61 °C or in
case of Blackout.