10
2
The operation of the Garda thermo-stove is a priority compared to the work of the combined boiler, since
the most economical fuel is pellet-operated.
The control unit is able to automatically manage the work between the two machines by connecting a 3-
way motorized valve.
In this case, the Boiler Probe (S1) detects the temperature of the machine body of the thermo-stove; once
the probe reaches the temperature of 50° (Th19), circulator P1 of the thermo-stove starts to exchange with
the system and the motorized valve P2 with thermostat set at 50° (Th56) opens the circuit between system
and thermo-stove.
Vice versa, when the temperature read by the S1 probe is lower than 50° (Th56), the 3-way motorized valve
(P2) exchanges, allowing the gas boiler to heat the domestic system.
Independent-operated system with DHW production.
System heating logic:
The thermo-stove is powered by pellets, the only heat generator for the heating and sanitary system (or, at
minimum, management between the thermo-stove and the gas boiler is carried out manually by the end
user).
Therefore, probe S1 detects the temperature in the boiler body and regulates the start of the circulator P1
once the machine reaches 50° (Th19).
DHW production logic:
The thermo-stove features a flow switch (FL) that detects the request of the hot water for domestic use;
with the operation of the flow switch, the electronic control unit automatically diverts the flow to the plate
exchanger through the motorized valve (P2) for the instantaneous production of domestic hot water.
Furthermore, as the thermo-stove detects the DHW request, it reaches its temperature of 70° (Th21-Ih21)
to guarantee constant production of hot water.
In this case, if the installed thermo-stove also produces domestic hot water, flow switch, plate exchanger
and motorized valve are already present inside the product.
Configuration 2 - P26 = 2 - Sanitary Boiler
To prepare the thermo-stove for heating a storage cylinder for sanitary use, also requires performing the
following operations:
Enter the System Menu - Default Settings, and set Technical Parameter P26 to 2.
Set the temperature you wish for water inside the Boiler (Factory settings 65°), in the Puffer
Thermostat, in the User Menu - Heating Management - Puffer Thermostat.
Connect an optional probe (NTC 10K @ 25°C) to terminals 34 and 35 of the electronic control
unit terminal board and firmly insert it into a boiler to allow the thermo-stove control unit to
detect the temperature inside the boiler.
