Hercules Condensing 20 User manual

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STHC ed 01/03 HERCULES Condensing
HERCULES Condensing
Room-sealed fan-assisted floor-standing
condensing boiler
HERCULES Condensing 20
HERCULES Condensing 27
HERCULES Condensing 27 ABT
HERCULES Condensing combines the advantages of
a room sealed boiler, featuring VICTRIX
microprocessor adjustment, with those of a floor
standing boiler with storage tank.
There are two different versions in the range with
powers of 20,210 kcal/h (23.5 kW) and 27,000 kcal/h
(31.4 kW), both equipped with an innovative total
premixing combustion system that guarantees minimal
emissions of pollutants and can be run on either natural
gas or LPG. Their high energy efficiency is rewarded
by the 4 star mark () in compliance with the
European Directive 92/42 EEC.
This boiler, thanks to its hydraulic circuit equipped with
a water-gas coil exchanger in AISI 316L stainless steel,
a hydraulic compensator and two circulation pumps,
is ideal where central heating systems require a high
output.
HERCULES Condensing 20-27 is designed to work
with the zone system control unit (max 3 zones) so
that 3 pumps and 3 ON-OFF room thermostats can be
controlled and the (optional) Remote Control to control
zone 1 can be used.
It is also possible to install a kit (optional) inside for
combined central heating systems with differentiated
temperatures (radiators and floor radiating panels).
General features.
Note: Note: This kit is already installed as a standard
feature on the HERCULES Condensing ABT versions.
The boiler of all models is designed for working with
and being connected to solar panel systems (optio-
nal).
The appliance is adjusted and controlled by an
electronic microprocessor board that, via a display,
shows boiler operating status (temperatures, safety
devices, etc.) and allows connection (optional) to the
Remote Control and to the Multisystem Distribution
Manifold.
The hot water circuit is equipped with a 5-litre expan-
sion tank and a 120-litre AISI 316 L stainless steel stor-
age tank which, besides its storage advantages, guar-
antees instant production of hot water.
HERCULES Condensing must be installed using the
aspiration and exhaust kit or the plastic
ducting systems (60 mm Ø rigid and 80 mm flexible)
made specifically for Immergas condensing boilers.

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STHC ed 01/03 HERCULES Condensing
Main dimensions and connections.
Legend:
RB - Low temperature return G 1”
MB - Low temperature delivery G 1”
RA - High temperature return G 3/4”
MA - High temperature delivery G 3/4”
G-Gas supply G 1/2”
U-Domestic hot water outlet G 1/2”
E-Domestic cold water inlet G 1/2”
RC - Recirculation G 1/2” (optional)
RP - Solar panels return G 3/4” (optional)
MP - Solar panels delivery G 3/4” (optional)
S-Condensate discharge syphon (minimum
inside diameter 13 mm Ø)
HERCULES Condensing
HERCULES Condensing ABT
Legend:
R3 - System return 3rd zone G 3/4” (optional)
M3 - System delivery 3rd zone G 3/4” (optional)
R2 - System return 2nd zone G 3/4” (optional)
M2 - System delivery 2nd zone G 3/4” (optional)
RB - Low temperature return G 1” (optional)
MB - Low temperature delivery G 1” (optional)
R1 - System return 1st zone G 3/4”
M1 - System delivery 1st zone G 3/4”
G-Gas supply G 1/2”
U-Domestic hot water outlet G 1/2”
E-Domestic cold water inlet G 1/2”
RC - Recycling G 1/2” (optional)
RP - Solar panels return G 3/4” (optional)
MP - Solar panels delivery G 3/4” (optional)
S-Condensate discharge syphon (minimum
inside diameter 13 mm Ø)

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STHC ed 01/03 HERCULES Condensing
Control panel.
Legend:
1-Central heating operation LED
2-Central heating temperature selector
3-Domestic hot water temperature v
4-Domestic hot water operation LED
5-Switch 0-Domestic Hot Water / Remote Control-Domestic Hot Water
and Central Heating
6-Storage tank thermometer
7-Manometer
8-Reset
9-Temperature and diagnostics display
10 - Burner operation LED

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STHC ed 01/03 HERCULES Condensing
Main components of HERCULES Condensing.
Legend:
1-Intakes (air A) - (flues F)
2-Condensing module lid
3-Ignition electrodes
4-Detection electrode
5-Limit NTC thermistor and central heating adjustment
6-Sleeve with housing Venturi
7-Air intake pipe
8-Overheat safety thermostat
9-Gas valve
10 - Gas valve outlet pressure test
11 - Domestic hot water expansion tank
12 - System safety valve, 3 bar
13 - 316 L stainless steel storage tank
14 - Domestic hot water NTC thermistor
15 - Storage tank drain cock
16 - System expansion tank
17 - Zone control unit (optional)
18 - System circulator zone 3 (optional)
19 - Combustion chamber
20 - Condensing module
21 - Burner
22 - System circulator zone 2 (optional)
23 - Fan
24 - System circulator zone 1
25 - Water pressure switch
26 - Electronic control unit
27 - Voltage Transformer
28 - 3-way diverter valve
29 - 3-way diverter valve motor
30 - System filling valve
31 - Recirculation pump (optional)
32 - 3-way delivery circulator
33 - Polyphosphate metering unit (optional)
34 - Condensate collector syphon
35 - System drainage fitting
36 - Draught diverter
37 - Positive signal pressure point
38 - Negative signal pressure point

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STHC ed 01/03 HERCULES Condensing
Main components HERCULES Condensing ABT.
Legend:
1-Intakes (air A) - (flues F)
2-Condensing module lid
3-Ignition electrodes
4-Detection electrode
5-Limit NTC thermistor and central heating system
adjustment High Temperature zone 1
6-Sleeve with housing Venturi
7-Air intake pipe
8-System overheat safety thermostat
High Temperature zone 1
9-Gas valve
10 - Gas valve outlet pressure test
11 - Domestic hot water expansion tank
12 - System safety valve, 3 bar
13 - 316L stainless steel storage tank
14 - Domestic hot water NTC thermistor
15 - Storage tank drain cock
16 - System expansion tank
17 - Zone control unit
18 - Zone 2 Low Temperature system circulator
19 - Combustion chamber
20 - Zone 2 Low Temperature system modulating NTC thermistor
21 - Zone 2 Low Temperature system overheat safety thermostat
22 - Burner
23 - Condensing module
24 - Fan
25 - Zone 1 High Temperature system circulator
26 - Water pressure switch
27 - Voltage Transformer
28 - Electronic control unit
29 - 3-way diverter valve
30 - 3-way diverter valve motor
31 - Plant filling valve
32 - Recirculation pump (optional)
33 - 3-way delivery circulator
34 - Polyphosphate metering unit (optional)
35 - Condensate collector syphon
36 - System drainage fitting
37 - Draught diverter
38 - Positive signal pressure point
39 - Negative signal pressure point

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Hydraulic diagram HERCULES Condensing.
Legend:
1-Condensate collector trap
2-Gas valve
3-Gas valve outlet press. point (P3)
4-Air/gas Venturi manifold
5-Fan
6 -Gas nozzle
7-Detection electrode
8-Burner
9-Condensing module lid
10 - Condensing module
11 - Draught diverter
12 - Air analyser intake
13 - Flue analyser intake
14 - ∆ p gas pressure point
15 - Limit NTC thermistor and c.h.
adjustment
16 - Overheat safety thermostat
17 - 3-way delivery circulator
18 - 3-way motorized diverter valve
19 - System expansion tank
20 - Hydraulic manifold
21 - Circulator zone 1
22 - 8 bar safety valve
23 - Polyphosphate metering unit
(optional)
24 - Domestic hot water expansion tank
25 - Flow limiter
26 - Domestic hot water one way valve
27 - System filling valve
28 - One way valve zone 1
29 - Cold water inlet filter
30 - System by-pass zone 1
31 - System drainig cock
32 - 3 bar safety valve
33 - Storage tank drainig cock
34 - 316L stainless steel storage tank
35 - Domestic hot water NTC thermistor
36 - Stainless steel coil for storage tank
37 - Air intake pipe
38 - Positive Venturi signal (P1)
39 - Negative Venturi signal (P2)
40 - Ignition electrodes
41 - Water pressure switch
42 - Magnesium anode
Low temperature configuration kit
(optional)
43 - Motorized mixing valve
44 - Low temperature delivery circulator
45 - Low temperature one way valve
46 - Low temperature by-pass
Zone kit configuration (optional)
47 - Circulator zone 2 and 3
48 - System by-pass zone 2 and 3
49 - One way valve zone 2 and 3
R1 - System return zone 1
R2 - System return zone 2 (optional)
R3 - System return zone 3 (optional)
M1 - System delivery zone 1
M2 - System delivery zone 2 (optional)
M3 - System delivery zone 3 (optional)
G-Gas supply
U-Domestic hot water outlet
E-Domestic hot water inlet
MP - Solar panels delivery (optional)
RP - Solar panels return (optional)
MB - Low temperature delivery (optional)
RB - Low temperature return (optional)
Low Temperature configuration kit
Standard configuration
Zone configuration kit

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STHC ed 01/03 HERCULES Condensing
A kit for connecting the storage tank to a solar panel
system can be installed (optional) inside both
HERCULES Condensing and HERCULES
Condensing ABT.
In the case of HERCULES Condensing 20 and 27, an
additional 2 pumps can also be installed inside which,
coupled with the zones control unit (see the D.I.M.
operating technical data sheet), make it possible to
divide the central heating system into 3 zones if wanted
while still enjoying a high input.
Hydraulic diagram HERCULES Condensing ABT.
Legend:
1-Condensate collector trap
2-Gas valve
3-Gas valve outlet pressure point (P3)
4-Air/gas Venturi manifold
5-Fan
6 -Gas nozzle
7-Detection electrode
8-Burner
9-Condensing module lid
10 - Condensing module
11 - Draught diverter
12 - Air analyser intake
13 - Flue analyser intake
14 - ∆ p gas pressure point
15 - Zone 1 limit NTC thermistor and High Temperature central
heating system adjustment
16 - Zone 1 High Temperature system overheat safety
thermostat
17 - 3-way delivery circulator
18 - Motorized 3-way diverter valve
19 - System expansion tank
20 - Hydraulic manifold
21 - Zone 1 High Temperature system delivery circulator
22 - Safety valve, 8 bar
23 - Polyphosphates metering unit (optional)
24 - Domestic hot water expansion tank
25 - Flow limiter
26 - Domestic hot water one way valve
27 - System filling valve
28 - Zone 1 High Temperature system one way valve
29 - Cold water inlet filter
30 - Zone 1 High Temperature system by-pass
31 - System emptying cock
32 - Safety valve, 3 bar
33 - Storage tank emptying cock
34 - 316L stainless steel storage tank
35 - Domestic hot water NTC thermistor
36 - Stainless steel coil for the storage tank
37 - Air intake pipe
38 - Positive Venturi signal (P1)
39 - Negative Venturi signal (P2)
40 - Ignition electrodes
41 -Water pressure switch
42 - Magnesium anode
43 - Motorized mixing valve
44 - Zone 2 Low Temperature system one way valve
45 - Zone 2 Low Temperature system delivery circulator
46 - Zone 2 Low Temperature system by-pass
47 - Zone 2 Low Temperature system overheat safety thermostat
48 - Zone 2 Low Temperature system modulating NTC thermistor
RA - Zone 1 High Temperature system return
MA - Zone 1 High Temperature system delivery
G-Gas supply
U-Domestic hot water outlet
E-Domestic cold water inlet
MP - Solar panels delivery (optional)
RP - Solar panels return (optional)
MB - Zone 2 Low Temperature system delivery
RB - Zone 2 Low Temperature system return
A low temperature kit can be installed inside
HERCULES Condensing 20 and 27 (optional) which,
thanks to a mixer valve and two circulators, allows
connection to combined central heating systems at
differentiated temperatures: a high temperature zone
(like radiators for instance) and a low temperature zone
(floor radiating panels for instance).
Note: This kit is a standard feature on the HERCULES
Condensing ABT version.

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STHC ed 01/03 HERCULES Condensing
Primary circuit (boiler circuit).
The primary circuit, with its control and safety devices,
starts working whenever there is a request for central
heating or domestic hot water.
Operation.
The heat contained in the products of combustion is
absorbed by the coil water-gas exchanger tubes
installed in the condensing module (10) which, in turn,
lets the heat off to the water that is made to circulate
inside it by the boiler’s pump (17).
The water is let into the hydraulic manifold (20) and
then to the system or it can be diverted to the storage
tank (34) coil (36).
This depends on the position of the electric 3-way
diverter valve (18) which, based on requirements, lets
it flow through the hydraulic manifold’s delivery and
return pipes or diverts it to the storage tank coil (36).
Boiler circulator (17).
It works on the primary circuit delivery at the primary
water-gas exchanger output (condensing module).
It is physically fixed to the primary exchanger’s delivery
pipe (return) and to the common of the 3-way diverter
valve (delivery) to which it is connected with threaded
fittings.
A threaded fitting on the body is used to fix the automatic
air vent directly (1).
1
Motorized 3-way diverter valve.
This electric 3-way diverter valve works on the delivery
side of the primary circuit and, based on requirements
(domestic hot water or central heating), lets boiler water
into the central heating system or into the storage tank
coil.
The hydraulic part consists of a brass unit (3) driven by
a motor that moves it as required.
Operation.
When it is necessary to reach the central heating or
domestic hot water position, the motor (2) is operated
by the adjustment board.
When the motor is running, at each 180°rotation it
causes the shutter to move (1) either into the central
heating or domestic hot water position.
When the position required is hydraulically reached it
causes the alternate opening and closing of one of the
two microswitches located inside the motor box (2).
Thus doing, power can be cutoff to the motor, locking it
in the position reached and motor operation enabled
only if a different request is made (domestic hot water
or central heating signal).
Hydraulic
compensator
delivery
Primary
circuit
delivery
Storage
tank coil
delivery
Primary circuit
filling
Primary Exchanger
(see VICTRIX Zeus).

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STHC ed 01/03 HERCULES Condensing
Safety and control devices.
No water pressure switch (1)
This switch detects the difference in pressure at the
ends of the boiler circulator (17) to which it is connected
by two copper pipes (2).
It is located by the side of the sealed chamber and
connected to a microswitch that stops the burner
working if there is no circulation inside the boiler.
It prevents the main exchanger overheating.
Automatic air vent (3).
This serves to automatically expel any gaseous
substances from the boiler circuit.
It is mounted on the pump delivery directly on the body.
3 bar safety valve 3 bar (4).
This ensure that the safety pressure (3 bar) is not
exceed in the primary circuit when activated, it expels
water from the return pipe.
It is located at the front of the boiler, under the sealed
chamber.
Expansion tank (5).
It compensates for the variations in volume when the
water is heated and limits pressure variations as well.
It has a preload pressure of 1 bar and a 12-litre capacity.
It is positioned at the back top right of the appliance.
3
1
2
5
4

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Central heating circuit.
HERCULES Condensing 20-27 operation with 1 circulator (Zone 1)
(standard configuration).
When a central heating request is made, the
modulating control board starts the boiler pump (17),
powers the heating pump (21) and powers the electric
3-way diverter valve motor (18) causing it to move into
the central heating position.
Thus doing the passage to the storage tank coil is
closed while the passage to the hydraulic manifold is
opened (20) and the primary circuit water is let into it.
Through the delivery (M1) and return (R1) pipes the
hot water is then let directly into the system by the
heating pump (21).
With the two circulators working together (17 and 21)
and by using an open hydraulic manifold (20), the flow
of water and head available are particularly high (see
the flow/head graph).
storage tank
delivery coil
storage tank
return coil

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Central heating circulator (21).
It works on system delivery after the hydraulic manifold
(20).
It is physically fixed to the system delivery pipe and
the boiler delivery manifold to which it is connected
with threaded fittings.
The automatic air vent (1) is fixed to the body by means
of a threaded fitting.
Hydraulic manifold (20) (compensator).
It is an open manifold to which both the boiler’s and
the system’s delivery and return pipes are connected
and, together with the boiler (17) and central heating
(21) pumps, provides a flow of water and head far
greater than what a traditional boiler can supply.
This is because circulation inside the primary circuit is
guaranteed by the boiler pump and therefore the central
heating circulator head is not reduced by the appliance’s
loss of head
This open manifold (20) also allows mixing of the
delivery water with part of the return water which means
the flow of water in the system is higher than what is
circulating through the boiler.
Safety and control devices.
By-pass (30-48-46).
It guarantees circulation in the primary circuit also when
the high resistance in the system does not allow it.
It is installed between the system’s delivery and return
connecting pipes.
System filters (60-61-62).
These filters prevent any impurities that may be in the
system from obstructing the primary circuit (exchanger)
and keeps the one way valves in perfect condition (28-
45-49) which, in turn, prevent leaks into the central
heating system while the domestic hot water part is
working.
They are in the bypass block by the system return pipe
connection.
System one way valves (28-45-49).
They prevent circulation in the system when the
domestic hot water pump is working.
They are in the return pipe, by the relative bypasses.
Note: The circulator, the system bypass, the
system filter and the zone 1 one way valve are
supplied as standard features while the others are
in the zone system connection kits (optional).
1
28-45-49
30-48-46
R
M
60-61-62

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HERCULES Condensing 20-27 operation with 2 or 3 circulators (optional)
(configuration with zone Kit).
If the system is going to be divided into zones (2 or 3)
a kit must be mounted inside the casing that requires
use of the zone control unit (50) (see D.I.M. operation
technical data sheet) and pumps in addition to those
used in the standard configuration (max. 2).
When these kits are installed, the pumps (47) are
connected to the delivery manifold (20) (return) and to
the corresponding system delivery pipe (delivery): the
pumps pump primary circuit water directly into this pipe.
The return pipes of the 2 or 3 zones are jointed to the
same manifold (20) connected to the primary
exchanger return.
Operation of each circulator (47 and 21) is subject to
the request to work by their room thermostats (or CAR
for zone no. 1) connected to the zone control unit.
For each supplementary zone, the kit includes a
circulator, a system bypass (48) and a one way valve
(49) to mount in the system return pipe.
Note: For the wiring diagram, settings, indications, etc.,
please see the Multisystem Distribution Manifold
(D.I.M.) technical data sheet.
storage tank
delivery coil
storage tank
return coil

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Head with total flow to the other zones with bypass
installed.
By using several circulators with the parallel pipe water-
gas exchanger, the system is supplied with a high flow
rate.
The graphs below show head trend available for the
system according to the flow that each pump supplies
at maximum speed with the bypasses installed
between delivery and return.
A = Head available zone 1 (standard feature) at third speed
B = Head available zone 1 (standard feature) at second speed
C = Head available for the additional zones at third speed
D = Head available for the additional zones at second speed
Head m H
2
O
Flow in Litres/h
A
B
C
D

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Operation with mixed systems (a standard feature for HERCULES Condensing ABT,
optional for HERCULES Condensing 20-27)
(configuration with Low Temperature Kit).
Coupling with a mixed system divided in two zones
necessitates installation of the “low temperature kit”
inside the casing.
To mount this kit you need a 3-way mixer valve (43)
and an adjustment unit (50) (see D.I.M. operation
technical data sheet) to control the valve as well as the
circulator (45).
Thanks to this system, the boiler can serve two zones
working at differentiated temperatures; a high
temperature zone (like radiators for example) and a
low temperature zone (floor radiating panels for
instance).
“high temperature” zone (zone 1).
This portion of the circuit is designed for working at a
temperature ideal for radiators, fan coils etc.
It is served by the standard circulator (21) and its
temperature is set by means of the boiler’s central
heating potentiometer.
“low temperature” zone (zone 2).
This portion of the circuit is designed for working with
floor panel heating systems.
It is served by a circulator (45) which, by means of a
motorized 3-way mixer valve (43), lets water into the
system at a constant temperature.
For this to happen, the 3-way valve (43) is controlled by
a unit (50) that alters it’s position according to the tem-
perature chosen (from 25 ° C to 45 ° C).
This temperature is set by way of the potentiometer
installed inside the control unit (50).
storage tank
delivery coil
storage tank
return coil

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The temperature of the delivery water is obtained by
mixing the delivery water of the high temperature circuit
with the return water of the low temperature circuit in a
variable quantity depending on requirements (see
hydraulic diagram on the previous page).
The NTC thermistor (48) connected to the control unit
(50) controls correct mixing.
Note: For the wiring diagram, settings, indications, etc.,
please see the Multisystem Distribution Manifold
(D.I.M.) technical sheet.
Head available in the high and low temperature
zones.
In the mixed system functioning mode, the use of more
than one circulator guarantees a greater flow to the
system.
When both system circulators (21 and 45) are working,
the maximum head available in both circuits varies in
proportion to the flow supplied in the other zone.
The following graphs show the head available in the
two zones.
Resistance m H
2
O
Flow in Litres/h
A
BC
D
A = Head available in High Temperature (zone 1) at third speed
B = Head available in High Temperature (zone 1) at second speed
C = Head available in Low Temperature (zone 2) at third speed
D = Head available in Low Temperature (zone 2) at second speed

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Domestic hot water circuit.
The domestic hot water circuit is involved each time
the temperature of the water inside the storage tank
needs bringing up to the value wanted, measured with
the domestic hot water NTC thermistor (35).
This occurs when domestic hot water is used and also
to restore heat losses.
Operation.
When a request is made for domestic hot water, the
modulating control board starts the boiler pump working
(17) and sees to powering the electric 3-way diverter
valve motor (18).
When the valve moves into the domestic hot water
position (see operation of the electric 3-way diverter
valve) it causes the hydraulic manifold delivery pipe to
close and simultaneously the passage towards the
storage tank coil (36) opens.
This prevents circulation in the central heating system
while it is allowed in the coil (36) which allows the cold
water to absorb the heat contained the primary circuit
water.
In this phase the central heating function is excluded,
the production of domestic hot water having priority.

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Storage tank.
It is a coil type storage tank made entirely in 316 L
stainless steel and has a capacity of 120 l.
It consists of an external casing, closed at the top by a
flange secured with 12 screws that, when needed, can
be removed for example, to extract the two coils (36)
connected in series to permit assembly of the solar
panel kit (see “solar panel kit” operation) They are made
with a concentric helix shaped stainless steel pipe and
it is through their walls that thermal exchange takes
place between the hot water in the primary circuit and
the water inside the storage tank.
A 30 l/min flow limiter is mounted on the fitting to the
cold water inlet pipe.
If necessary, the storage tank can be extracted from
the front, sliding it out on the two “slides” (51) it stands
on.
The following devices ensure correct operation and
integrity:
Anode (42).
This is in the storage tank and protects it against
galvanic currents. It is screwed on the recycling tube
probe (52) on the top flange.
Polyphosphates metering unit (optional).
This prevents limescale depositing on the coil walls.
The kit is mounted internally, connecting it to the
domestic cold water inlet.
It can be accessed by opening the side door.
Cold water manifold unit (53).
This is located on the cold water inlet and connected
to the expansion tank (24) and to the filling valve (27).
It contains a filter and a one way valve that prevents
the increase in pressure - when the domestic water is
heated - from sending the water back to the water
mains.
Recirculation kit (optional).
With this kit it is possible to connect to a domestic hot
water recycling system if one is installed.
The kit includes a circulator (54) housed inside the
casing with the relative template connecting pipe.
Storage tank NTC thermistor (35).
Thanks to this device the modulating control board can
detect the temperature of the water inside the storage
tank.
It is inserted inside a bulb holder against the external
wall.
Safety valve (22).
This valve prevents the safety pressure being exceeded
inside the storage tank (8 bar).
It is mounted on the domestic cold water inlet pipe
after the domestic water one way valve.
Domestic hot water expansion tank (24).
It compensates for the variations in volume that result
from heating the water inside the storage tank.
It is connected to the cold water inlet and has a preload
pressure of 3.5 bar and a capacity of 5 l.

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The two coils (4-5) of HERCULES Condensing are
arranged vertically, one above the other, and in the
standard configuration they are hydraulically connected
in series (see domestic hot water hydraulic diagram)
so that their total surface guarantees the heat exchange
of all the power supplied by the appliance.
Their dimensions differ so that, under normal working
conditions, the top one (4) exchanges 24,000 kcal/h
and the bottom one (5) 4,000 kcal/h.
For installation of the “solar panel kit” the two coils have
to be separated and the one at the bottom of the storage
tank (5) connected to the MP (panel delivery) and RP
(panel return) fittings of the boiler connection unit. Thus
doing, while the other coil (4) is still connected to the
boiler circuit, this one is connected to an external solar
panel system (not supplied in the kit).
Application of the base drawing above, foresees the
use of a control unit (3) that detects storage tank water
temperature by means of a sensor (6) that substitutes
the domestic hot water NTC thermistor (35), after the
latter has been moved to the intermediate bulb holder.
The control unit (3) commands the circulator (2) when
the sensor (6) detects a temperature below the
requested value and below that of the water heated by
the panels.
If the solar energy is not enough to meet requirements
(prolonged use of water, not much sun, etc.) and the
boiler’s domestic hot water NTC thermistor (35)
measures a temperature that is below the set value,
the burner starts and, by means of the top coil (4),
instant production of domestic hot water is guaranteed
(24,000 kcal/h).
Graph of solar panel circuit loss.
The solar panel circuit inside the boiler (coil and
connecting pipes) suffers losses of head, shown in the
graph here on the right, which must be borne in mind
when dimensioning the circulator (2).
Head m H
2
O
Flow in litres/h
Operation with the solar panel kit (optional for all versions).
Boiler
circuit delivery
Boiler
circuit return

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STHC ed 01/03 HERCULES Condensing
Air-gas circuit.
Operation
(See VICTRIX Zeus).
Gas valve
(See VICTRIX Zeus).
Fan
(See VICTRIX Zeus).
Venturi
(See VICTRIX Zeus).
Burner
(See VICTRIX Zeus).
Air-gas adjustments.
Adjusting the minimum and nominal
heat output
(See VICTRIX Zeus).
Adjusting the air-gas ratio (off-set)
(See VICTRIX Zeus).
Gas conversion
(See VICTRIX Zeus).
Flues circuit.
Operation
(See VICTRIX Zeus).
Draught diverter
(See VICTRIX Zeus).
Condensation drainage siphon (4)
(See VICTRIX Zeus).
Venturi tapping points (P1-P2)
(See VICTRIX Zeus).
Air-flues intakes (8-9)
(See VICTRIX Zeus).
Aspiration and exhaust systems.
(see aspiration and exhaust terminals instructions).
Conventional configuration (type B23) for
indoor installation.
(See VICTRIX Zeus).
Room sealed fan-assisted configuration
(type C).
(See VICTRIX Zeus).

20
STHC ed 01/03 HERCULES Condensing
Electrical circuit.
The HERCULES Condensing electric circuit is served
completely by an electronic microprocessor board that
controls generator functions.
Part of the control and safety devices operate at mains
voltage (230 Vac) and part at low voltage.
230 V AC circuit.
Safety and control devices.
It detects ignition of the burner when the flame investes it.
It is connected to the ignition board detection circuit.
Detection electrode
(E3)
It interrupts power to the circuit when the current absorbed is
more than 3.15 A.
It is plugged into the modulating control board.
Line fuse 3.15 AF 250 V
Fuse
It interrupts power to the transformer (230V/24V) of the low
voltage circuit when the current absorbed is more than 315 mA.
It is plugged into the modulating control board.
Transformer fuse
230V / 24V
315 mA 250 V
Fuse
Legend:
CR - Remote Control (optional)
DL1 - Central heating function LED
DL2 - Domestic hot water function LED
DL3 - Flame presence LED
E1-E2 - Ignition electrodes
E3 - Detection electrode
F-Line fuse
IG - Main switch
MPC - Boiler circulator
MPR - Domestic hot water circulator
MV - Fan
NB - Storage tank NTC thermistor
NE - External probe (optional)
NR - Central heating NTC thermistor
P1 - Room thermostat bridge
PU1 - Button reset
SP - No water pressure switch
T-Transformer fuse
TA - ON/OFF room thermostat (optional)
TS -Overheat safety thermostat
TT -Voltage transformer
U1 - Rectifier inside the V.G. connector
VD - 3-way diverter valve
V-G-Gas valve
230 V ~
power supply
Zone plant
(optional)
230 V ~ max.
2A auxiliary
output
Modulating control
board
Ignition
board
Display
board