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DHW PRODUCTION
It is possible to supply hot water for various sanitary and domestic uses by connecting a suitable storage
tank (thermo-boiler).
IMPORTANT! the boiler absorbed heating power will consequently reduce the heating system kW.
During transport loosening and/or failure of the hydraulic system gaskets could occur, causing water
leaks during the stove operation. Therefore check the tightening of the connections to the circulators
and heat chamber during water loading and the first operating hours of the stove.
In case of a multi-zone system, to avoid overheating the heat chamber internal water, leave a part of
the system constantly open, thus avoiding the simultaneous closure of all areas. The open system
part must dispose of a power equal to that developed by the operating stove at reduced power (4.5
kW).
The heating power of the stove is to be established based on the heating requirements of the building
in which it is placed. The system must have all the components needed for a proper operation. In
addition, it is advised to insert valves that allow (if necessary) to isolate the stove from the system. The
stove is internally provided with a heating and sanitary (optional) hydraulic circuit.
If it is necessary to connect the stove to a boiler system, it is advised to insert a thermally isolated heat
exchanger (25-35 kW), or an accumulator-puffer based on the system type.
The hydraulic system is equipped with a 6 lt closed surge tank with a precharge pressure of 1 bar. To
display the heat chamber pressure, press and hold key 5 on the display for a few seconds. Digits
indicating the pressure (letter b = bar) will appear on the second row. The ideal pressure must be
between 1 and 1.5 bar. If the pressure exceeds 2 bar, the stove will enter the alarm mode. Regularly
check the heat chamber and the precharge pressure of the surge tank and if necessary refill. Consult a
qualified technician if in doubt.
Installation advice
The 6 liter built-in expansion tank is sized for a system containing a maximum of 75/80 liters of water,
including 24 liters (H18) and 35 liters (H25-HC25) contained in the stove. Install an additional
expansion vessel if the system exceeds these quantities.
Use expansion tanks loaded at 1 bar.
Using a dirt separator filter can prevent malfunctions due to solid residues in the system.
The built-in recirculation pump has a prevalence of about 7.5m. If the system requires longer lifts, a
second pump should be installed.
Provide an anti-condensation valve or, in some cases, guarantee greater durability and efficiency of
the stove, consult the technician who will make the system.
Water drain in overpressure
female 1/2" heating.
Heating DELIVERY Male 1”
Water drain in DHW overpressure Female 1/2"
DHW DELIVERY Male 1/2"
Water supply Male 1/2"
Heating RETURN Male 1”
System load Male 3/4"