Unical S 24, Manual

Page: 8 / 52

8
(*) The frost protection is always active.
Even disabling the CH and DHW services.
ATTENTION (*) see general warn-
ings 1.1
The heating only models are NOT
suitable for the production of water
for human consumption according
to Ministerial Decree D.M. 174/2004.
ATTENTION!
ANY DAMAGE TO THE BOILER
CAUSED BY THE FORMATION OF
FOULING OR BY CORROSIVE wATER
wILL NOT BE COVERED BY THE
wARRANTY.
1.7 - wATER TREATMENT
The treatment of the supply water
allows to prevent inconveniences
and maintain the functionality and
efficiency of the generator over time.
The ideal water pH in heating systems
must be within:
To minimise corrosion, it is crucial to
use a corrosion inhibitor; in order for
it to work properly, the metal surfac
-
es must be clean.
(see system protection ACCESSO-
RIES sect. in domestic price list)
VALUE
MIN MAX
PH 6.5
8
Hardness [°fr]
9
15
1.8 - BOILER ANTIFREEZE
PROTECTION (*)
P
O
S
ANTIFREEZE FUNCTION
Power supplies
11 - SR
(*) Status
function
antifreeze
Actions
Electric Gas
1 ON ON
< 6 °C
ON
- Burner and Pump ON until T > 14°C
2
ON
OFF
< 2 °C
ON
Only when both the power supplies are ON:
- Burner and Pump OFF until T > 5°C
- When T > 5°C then Burner and Pump
ON until T > 14°C.
OFF
ON
OFF OFF
(*) Sensor 11 par. 2.2
This protection can intervene only
i f the electricity and gas supplies are
connected.
I f one of the two is not available and
upon reset
11 (SR)
a temperature of
<
2 °C is detected, the appliance will
behave as described in tab.
pos 2.
The heating system can be protected
effectively from frost by using
antifreeze products with inhibitor
for heating systems (specific for
multidmetal).
Do not use car engine antifreeze
products as they could damage the
water gaskets.