Immergas VICTRIX ZEUS 20 User manual

VICTRIX Zeus
Condensation-type wall-hung
room sealed fan-assisted boiler
with stainless steel storage tank.
VICTRIX Zeus

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VICTRIX ZEUS
Condensation-type wall-hung room sealed
fan-assisted boiler with Gaudium Ma-
gnum device.
VICTRIX Zeus 20
VICTRIX Zeus 27
General features.
VICTRIX Zeus is a condensation-type wall-hung room sea-
led fan-assisted boiler featuring a “Gaudium Magnum” devi-
ce for fully exploiting the characteristics of this 54 l boiler in
Aisi 316L stainless steel.
ere are two versions in the range with working outputs of
23.5 kW (20210 kcal/h) and 31.4 kW (27000 kcal/h) and
both feature an innovative total premix combustion system
that ensures very low pollutant emissions and enables the boi-
ler to run on natural gas and LPG.
e high energy output has been awarded the 4-star mark
(´´´´) in conformity with P.D. 660/96.
e appliance is regulated and controlled by means of a prin-
ted microprocessor control board which, through a monitor,
displays the state of boiler operation (temperature, safety devi-
ces, etc.) and enables it to be connected (optional) to the Ami-
co Remote Control, to the area unit and to the Multisystem
Water Disconnector.
e hydraulic circuit features a coil water-gas exchanger in
STAINLESS steel, a 3-way electric valve and a 2 l d.h.w.
expansion vessel.
VICTRIX Zeus must be installed using the aspiration/drai-
nage kit or the piping system (Ø 60 mm rigid and Ø 80 mm
flexible) made of plastic material and expressly conceived for
Immergas condensation boilers.

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VICTRIX Zeus main dimensions.
VICTRIX Zeus control panel.
Legend:
G - Gas supply
R - System return
M - System delivery
RC - Recirculation (optional)
U - D.h.w. outlet
E - D.h.w. inlet
V - Power connection
S - Condensation runoff (minimum internal
diameter of Ø 13 mm)
Legend:
1 - Heating operating indicator
2 - Heating temperature switch
3 - D.h.w. temperature switch
4 - D.h.w. operating indicator
5 - Switch 0 - D.h.w. and remote control - D.h.w. and heating
6 - Gaudium Magnum operating switch
7 - Gaudium Magnum operating indicator
8 - Storage tank thermometer
9 - Boiler pressure gauge
10 - Reset
11 - Temperature and diagnostic display
12 - Burner operating indicator
Height (mm) Width (mm) Depth (mm)
900 600 450
CONNECTIONS
GAS SYSTEM DOMESTIC
HOT WATER
G R M U E
1/2” 3/4” 3/4” 1/2” 1/2”

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VICTRIX Zeus main components.
Legend:
1 - Intake sockets (air A) - (fumes F)
2 - Fume thermostat
3 - Condensation module lid
4 - Ignition electrodes
5 - Detection electrode
6 - Heating adjustment and limit NTC probe
7 - Sleeve with housing for Venturi
8 - Air inlet pipe
9 - Overtemperature safety thermostat
10 - Air outlet valve
11 - Circulator
12 - Motorised three-way valve
13 - Gas valve
14 - System filling cock
15 - Expansion vessel
16 - Combustion chamber
17 - Stainless steel storage tank 316L
18 - Condensation module
19 - Air fan
20 - Electronic control unit
21 - Maximum flow limit thermostat
22 - D.h.w. NTC probe
23 - Voltage transformer
24 - Water trap syphon
25 - Circulator safety flow switch
26 - System 3-bar safety valve
27 - D.h.w. 8-bar safety valve
28 - Gaudium Magnum device
29 - Storage tank emptying cock
30 - Draught diverter
31 - Positive signal pressure point
32 - Negative signal pressure point
33 - Burner
34 - Gas valve outlet pressure test
35 - D.h.w. expansion vessel
36 - System emptying cock
37 - Adjustable by-pass
(from the serial number 2753798 for VICTRIX Zeus 20)
(from the serial number 2731813 for VICTRIX Zeus 27)

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Hydraulic circuit.
Legend:
1 - Storage tank emptying valve
2 - One way valve
3 - Stainless steel coil for storage tank
4 - Water trap syphon
5 - Stainless steel storage tank 316L
6 - Magnesium anode
7 - Gas valve
8 - Gas valve outlet pressure point (P3)
9 - Air fan
10 - Gas nozzle
11 - Detection electrode
12 - Burner
13 - Condensation module lid
14 - Condensation module
15 - Fume thermostat
16 - Draught diverter
17 - Air analyser trap
18 - Fume analyser trap
19 - ∆p gas pressure point
20 - Heating adjustment and limit NTC probe
21 - Ignition electrode
22 - Air inlet pipe
23 - Venturi air/gas manifold
24 - Venturi negative signal (P2)
25 - Venturi positive signal (P1)
26 - Max drawing limit thremostat
27 - Overtemperature safety thermostat
28 - Expansion vessel
29 - Automatic air outlet valve
30 - Circulator
31 - Pump pressure switch microswitch
32 - Pump pressure switch
33 - D.h.w. NTC probe
34 - System emptying cock
35 - Motorised 3-way valve
36 - System filling valve
37 - Adjustable by-pass
38 - 3 bar safety valve
39 - D.h.w. expansion vessel
40 - 8 bar safety valve
41 - Gaudium Magnum device
42 - Cold water inlet filter
G - Gas supply
S - Condensate discharge
U - D.h.w. outlet
E - D.h.w. inlet
R - System return
M - System delivery
(from the serial number 2753798 for VICTRIX Zeus 20)
(from the serial number 2731813 for VICTRIX Zeus 27)

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Primary circuit (boiler circuit).
e primary circuit with relevant control and safety devices is
triggered each time there is a request for central heating or
domestic hot water.
Operation.
e heat contained in the products produced by combustion
is absorbed by the pipes of the coil water-gas exchanger fitted
in the condensation module (14) which, in turn, transfers
this to the water circulating inside thanks to the boiler pump
(30).
When the boiler is working for water heating only, water en-
ters the system directly. is depends on the position of the
3-way electric valve (35) which, depending on the type of
request, permits flow through the flow pipe (M) and return
pipe (R) of the system or else deviates flow through the sto-
rage tank coil (3).
Flow-head graph.
e trend of the curve that represents the flow-head ratio, de-
pends on how the system by-pass is adjusted. Depending on the
position, it provides the system with a higher or smaller head.
e following graph are the curves for every pump speed.
Circulator.
e circulator works on the primary circuit return and it is phy-
sically located on the electric three-way valve brass assembly.
It is connected to the enbloc and primary circuit exchanger by
means of a threaded connecting pieces.
e casing features a threaded union used to directly secure
the automatic release valve (1).
A = Head available to the system on maximum speed with the by-pass
off (adjustment screw fully tightened)
B = Head available to the system on maximum speed (screw tightened
4.5 turns compared to the screw completely loose)
C = Head available to the system on maximum speed with the by-pass
open (adjustment screw completely loose)
A
B
C
A
B
C
A = Head available to the system on maximum speed with the by-pass
off (adjustment screw fully tightened)
B = Head available to the system on maximum speed (screw tightened
4.5 turns compared to the screw completely loose)
C = Head available to the system on maximum speed with the by-pass
open (adjustment screw completely loose)
VICTRIX Zeus 20
VICTRIX Zeus 27
VICTRIX Zeus 20
VICTRIX Zeus 27
1
1
Flow Litres/h
Head (kPa)
Head (m H2O)
Flow Litres/h
Head (kPa)
Head (m H2O)
e hot water for heating and domestic use is produced by
a primary and a secondary (d.h.w.) circuit used according to
needs.

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Primary exchanger
(condensation module).
It consists of a casing containing 5 or 6 coil elements (depend-
ing on the model).
In turn, each element consists of 5 elliptic pipe spirals.
e whole module is made of stainless steel and the inner part
comprises a sealed combustion chamber and condensation
chamber (2).
VICTRIX Zeus 20.
e first four elements are, in fact, involved directly in the ac-
tion of the cylindrical burner, fitted to the front, while the fifth
is located in the condensation chamber which is separated from
the combustion chamber by a metal plate (see fumes circuit).
VICTRIX Zeus 27.
e first five elements are involved directly in the action of the
cylindrical burner, fitted to the front, while the sixth is located
in the condensation chamber which is separated from the
combustion chamber by a metal plate (see fumes circuit).
To minimise load losses and increase the flow available for the
system, the delivery consists of the parallel connection of the
first three elements (VICTRIX Zeus 20) or first four elements
(VICTRIX Zeus 27), while the return consists of a parallel
connection of the last two elements.
e exchanger inlet is connected to the pump delivery and the
outlet, on which the NTC heating sensor (1) is positioned, is
connected to the primary circuit delivery.
Connection to the delivery and return pipes of the primary
circuit is of the coupling type with an O ring seal.
e draught diverter (3) is connected at the back by means of
a seal locked by a metal ring.
Condensation is drained from the bottom.
FUMES
CONDENSATION
RUNOFF
DELIVERY
RETURN
3
2
1

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Safety devices and controls.
System adjustable by-pass (6).
is ensures water circulation in the primary circuit (between
delivery and return) even when this is prevented by the high
resistance of the system.
It is mounted on the delivery supply header and it can be
adjusted by means of a screw accessible from the bottom part
of the valve support plate.
System filling unit (5).
is cock is positioned between the boiler circuit and the do-
mestic cold water inlet and makes it possible to pressurise the
heating system.
Downstream of the cock is an one way valve (“2” hydraulic
circuit) that prevents water accidentally passing from the pri-
mary circuit to the water mains (d.h.w. circuit).
Its housing is in the bottom part of the enbloc to which it is
screwed.
No-water pressure switch (2).
is reads the pressure difference at the ends of the circula-
tor.
It is housed on the delivery manifold unit (1) and is coupled
to a microswitch (3) that prevents boiler operation when the
pump is blocked or there is no water in the boiler circuit.
is way overheating of the main exchanger is prevented.
Automatic air vent (7).
For automatic release of any gaseous substances in the boiler
circuit.
It is secured to the pump supply directly on the casing.
3-bar safety valve (4).
is prevents safety pressure being exceeded in the circuit (3
bar).
It is fitted on the front to the outer side by means of a socket-
head screw.
Operation of this valve causes water to exit from the delivery
pipe.
Expansion vessel (8).
Offsets volume changes resulting from water heating thereby
restricting pressure changes.
It has a capacity of 10 l and an 1.0 bar pre-load pressure.
It is located in front of the storage tank in the front section
of the appliance.
System
delivery
7
8

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Secondary circuit (domestic hot water circuit).
e d.h.w. circuit is engaged every time the temperature of
the water in the storage tank (2) has to be brought to the
desired value. is is measured by means of the d.h.w. NTC
sensor (9).
is can occur both when d.h.w. drawing is run and to make
good losses caused by heat dispersion.
Operation.
Following a d.h.w. request, the modulation board starts the
boiler pump (7) and drives the motor of the 3-way electric
valve (8).
e consequent movement of the valve in d.h.w. position (see
3-way electric valve operation) causes the return pipe (R) to
close and, at the same time, the opening of access towards the
storage tank coil (4).
is way, circulation is prevented in the heating system, while
it is allowed in the coil (4) which, through its walls, permits
the cold water to absorb the heat from the water in the pri-
mary circuit.
At this stage, the heating function is disengaged because the
production of d.h.w. has priority.

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Cold
water
inlet
Hot
water
outlet
Coil
delivery
Coil
return
11
Storage tank.
e storage tank is a coil unit made entirely of AISI 316 L
stainless steel totally insulated with self-extinguishing poly-
styrene with a working capacity of 54 l.
It consists of an outer jacket enclosed in the bottom part by a
flange secured by 12 screws.
Inside is a cylindrical pipe made of STAINLESS steel shaped
like a concentric spiral (coil) that develops along the entire
height of the storage tank and through the walls of which the
heat exchange occurs between the hot water of the primary
circuit and the water in the storage tank.
is ensures the water in the storage tank is always at a con-
stant temperature and, in the case of a water request, results
in the instantaneous production of d.h.w. (20000 kcal/h or
27000 kcal/h).
If necessary, the coil can be removed from the storage tank
after taking off the lower inspection flange.
Proper operation and integrity are provided by the following
devices:
Anode (1).
is is fitted in the storage tank and protects it against the
effects of galvanic currents.
It is screwed onto the upper flange.
Polyphosphate metering unit (optional).
Prevents scale deposits on the coil walls.
e kit is fitted at the cold domestic water inlet.
Gaudium Magnum (6).
(see Gaudium Magnum description and operation).
Re-circulation kit (optional).
Permits connecting the pipes of any d.h.w. re-circulation sy-
stem.
It consists of a pipe that is fitted in the storage tank after
removing the anode and the relevant cap.
When the kit is installed, the anode must be screwed onto the
end of the pipe.
NTC storage tank sensor (NB) (9).
Enables the modulation board to measure the temperature of
the water in the storage tank.
It is fitted to the outer wall of the storage tank and is inserted
in an immersion drawing.
Maximum flow limit thermostat (3).
is is a clicson thermostat that controls the solenoid valve of
the Gaudium Magnum device.
It is fastened in contact with the outer wall of the storage
tank.
Safety valve unit (13).
is group is located in the bottom part of the storage unit
near the cold domestic water inlet.
Besides an 8-bar valve (10) which prevents safety pressure
being exceeded inside the storage tank, it comprises:
- a filter, a storage tank drain cock with rubber holder con-
nector (12) and an one way valve (see “5” d.h.w. hydraulic
circuit) to prevent the increase in pressure resulting from
d.h.w heating causing a return towards the water mains.
D.h.w. expansion vessel (11).
Offsets the changes in volume caused by the heating of the
water in the storage tank.
It is connected to the safety valve unit and has a capacity of 2
l with pre-load pressure of 3.5 bar.

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Gaudium Magnum.
is device is connected between the cold domestic water
inlet (inlet) and the safety valve unit (outlet).
Inside it features a solenoid valve which, in idle condition,
permits the water to flow through a flow limiting device
from 8 l/min (Victrix Zeus 20) or 10 l/min (Victrix Zeus
27) while, when it is operated, it opens a supplementary
passage which is devoid a flow limiting device from 6 l/min
that can higher the water passage of 50%.
Operation.
e valve is enabled electrically (230 VAC) moving the
“Gaudium Magnum” switch on the control panel to
position ( ) and is engaged when the maximum draw limit
thermostat (3), on the storage tank, reads a temperature
over 50 °C.
When the temperature drops below 41 °C, the maximum
draw limit thermostat (3) disables the valve automatically.
is permits drawing a considerable amount of water when
the temperature of the storage tank is high, while when it is
low, the flow of hot water is restricted thereby enabling the
temperature of the d.h.w. to quickly rise again.
By returning the Gaudium Magnum switch to “0” the
valve remains constantly disengaged.
NOTE: to ensure the “Gaudium Magnum” function engages,
the d.h.w. temperature adjustment knob must be in a position
between 6 and 9.

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Motorised 3-way valve.
is is a 3-way electric valve operating on the return pipe
of the primary circuit that permits, according to the type of
request (d.h.w. or central heating), running boiler water into
the central heating system or into the storage tank coil.
is depends on the position of the shutter (3) which impedes
transit towards the system and at the same time permits this
towards the storage tank (d.h.w. position) or vice versa (central
heating position).
Movement of the shutter (3) in both positions is achieved by
energising the motor (1).
Operation.
When the central heating or d.h.w. position has to be achieved,
the motor (1) is operated by the modulation board.
Operation of the motor, whose number of revs is reduced
by a special system of gears, involves rotation of a disc (6)
fastened eccentrically on the shaft of the motor.
Movement of this disc causes the movement of a special
coupling (5) which, at each 180° rotation, compresses (heating
position) or releases (d.h.w. position) the contrast spring of the
shutter (4).Hydraulic achievement of the required position
causes, alternately, the opening of a limit switch (2) and the
closing of the other.
is permits de-energising the motor and locking this in the
achieved position and enabling motor operation only when a
different request is made (d.h.w. or central heating signal).
PLANT RETURN
PUMP RETURN
COIL
RETURN
D.H.W.
SIGNAL
HEATING
SIGNAL
COMMON
PUMP RETURN
PLANT
RETURN
COIL
RETURN

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Air-gas circuit.
e circuit consists of a total pre-mix combustion system
comprising a fan (5), a pneumatic type gas valve (7), a Venturi
pipe (3) and a special cylindrical burner (8) that works inside
the condensation module.
Operation.
e fan (5) is controlled by the modulating control board that
varies speed according to the required output.
anks to the fan, combustion air is taken from outside the
sealed chamber and sent through a duct where a Venturi pipe
(3) is installed.
A positive pressure signal (P1) is located at the Venturi (3)
inlet which can be varied in a way directly proportional to the
quantity of air extracted by the fan (5) and which is detected
by means of a pressure point connected to the pneumatic gas
valve (7).
e electrical supply of the main valve coils causes both internal
shutters to open and the gas to flow through, whose outlet
pressure is regulated by the same pneumatic valve with a 1:1
ratio at pressure “P1”.
rough nozzle (4), the gas is injected at the inlet of the Venturi
pipe (3) where pre-mixing begins with the combustion air.
e resulting mix is ignited on the cylindrical burner surface
(8) by a spark from the ignition electrodes (9).
Gas valve.
e gas valve features two main coils controlled by the electric
circuit and a pneumatic control unit that modulates the exit-
ing gas pressure at a 1:1 ratio at pressure (P1) detected at the
Venturi pipe inlet.
e ratio between air and gas pressures (off-set) are set on this
valve (see gas regulation).
Electrical coils (4).
Two ON-OFF type coils, powered (230 Vac) by the ignition
unit when the burner has to be ignited.
ey are connected in series and energised by mains voltage rec-
tified by means of a diode bridge inside the connector (3).
Pneumatic unit (2).
With this unit the outlet pressure can be varied at a 1:1 ratio
at pressure (P1) detected at the Venturi pipe inlet which is
restored to the valve through a silicone pipe (1).
anks to this system, the percentages in the air-gas mix remain
constant at optimum values on the entire modulation field thus
ensuring an almost constant combustion performance.
By loosening the cap, the off-set setscrew can be accessed (2)
by means of which the air-gas ratio can be set.
is is only necessary if, after having analysed the fumes,
incorrect combustion values are found (see air-gas ratio ad-
justment).
1
2
34

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Fan.
is operates upstream from the combustion chamber and is
physically positioned at the bottom of the sealed chamber.
It is controlled by the modulating control board with a posi-
tive square wave signal with a variable ON-OFF (duty-cycle)
ratio.
Its speed is controlled (from about 1100 to about 5000 rpm)
according to the required output and is controlled by means
of a Hall effect sensor which reads the number of rpm.
e fan extracts the combustion air from the top of the sealed
chamber through a plastic tube (1) that helps reduce noise and
optimises burner ignition.
Variations in the flow of air entering the mixing duct results
in a variation in the pressure (P1) signal at the inlet of the
Venturi pipe and enables the pneumatic valve to regulate
exiting gas pressure.
Venturi.
e Venturi pipe (1) is fitted in a sealed duct, inside which the
combustion air and gas are mixed.
e air is driven to the bottom of the duct by the fan, while
the exiting gas from the valve is injected by a nozzle (2) at the
Venturi pipe (1) inlet.
e transit of air in the pipe creates vacuum (“Venturi effect”)
which, through the 4 holes (3) in the base, “drags” the gas
inside and mixes it with the air.
e nozzle (2) differs in diameter according to whether natural
gas or LPG is used; working with both gases at a more or less
constant pressure, its section determines correct gas flow.
At the ends of the Venturi pipe are two pressure points through
which the input (P1) and output (P2) signals are read.
By means of two silicone tubes, these signals are carried,
respectively, to the pneumatic gas valve, which regulates gas
pressure, and to the negative pressure point (P2) located at the
top of the sealed chamber.
Burner.
is is a cylindrical burner (5) consisting of three concentric
plates appropriately perforated and made of a special steel that
is very resistant to high temperatures and corrosion.
It is fitted inside the condensation module, in a sealed com-
bustion chamber closed by a flange (4) to which the burner is
secured and which ensures direct connection with the air-gas
mix duct (6).
Pre-mixing, the absence of secondary air and the construction
characteristics of the burner ensure high combustion perform-
ance and very low pollutant emissions (see technical data and
according to the model).
1
GAS AIR
1
2
3
6
9
P2 P1
8
7
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anks to the high resistance to temperatures of the materials
used, it is possible to operate with a very low flame up to a
minimum output of:
VICTRIX Zeus 20 = 4.000 kcal/h (20% of nominal heat power).
VICTRIX Zeus 27 = 5.298 kcal/h (20% of nominal heat power).
Ignition is by means of an electronic board (control unit) that
controls the ignition (7) and detection (9) electrodes.
Ignition electrodes (7).
These are controlled by the ignition control unit which
produces an electrical charge between them that ignites the
air-gas mix.
e electrode (8) has no ceramic insulation and is earthed
directly (blind electrode).
ey are positioned on the right of the burner and secured
on the flange (4).
Detection electrode (9).
is is controlled by the control unit and detects burner
ignition.
It also acts as a fumes safety device when any air intake or
combustion product extraction problems cause the burner to
operate below minimum output.
In this case, in fact, we have a flame-stop condition because
there is no detection by the electrode.
To protect the combustion circuit, this same stoppage prevents
the module from filling with water whenever there are conden-
sation drainage problems (syphon blockage, etc.).
It is fixed on the left of the burner flange (4).
Note: in case of ignition block it’s required to check the distan-
ces of the ignition electrodes and of the detection electrodes
sticking to the values shown in the figures below.
GAS AIR
1
2
3
6
9
P2 P1
8
7
45
VICTRIX Zeus 20 VICTRIX Zeus 27

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Air-gas adjustment.
Calibration of the total pre-mix combustion system envisages,
whenever there is the need, adjustment of the nominal heat
output and air-gas ratio (off-set).
With the exception of the nominal output adjustment, which
must nonetheless be done during initial inspection, the two
operations are normally only required after a gas conversion,
after extraordinary maintenance work (replacing a component
part of the air-gas circuit, replacing the modulating control board,
etc.) or when the appliance needs recalibrating.
Adjusting nominal and minimum heat output.
e availability of maximum output is related to the length
of the suction and exhaust pipes. If this is extended, we have
a slight reduction in the quantity (flow) of air at the inlet and
consequently, also of the pressure of the burnt gas.
e boiler is factory set for operation with a horizontal con-
centric kit, 60/100Ø, 1 m long, and consequently the use of
flue accessories with higher or lower load losses requires control
and, if necessary, adjustment of the nominal output.
e operation must be performed in the following way and
observing the values given in the output adjustment table:
- connect a differential pressure gauge to pressure points P1
(positive point) and P2 (negative point) located at the top of
the sealed chamber (in this way the pressure difference can be
read at the ends of the Venturi pipe (P1-P2) and a pressure signal
is measured that corresponds to the actual air-gas mix flow to
the burner).
- start the appliance in the chimneysweep mode and set the
heating output trimmer on the modulating control board
to maximum (see modulating control board operation).
- after at least 5 minutes’ operation, adjust the maximum fan
speed adjustment trimmer located on the modulating con-
trol board (see modulating control board operation) until you
have a pressure reading (P1-P2) corresponding to nominal
output.
Speed increases by turning clockwise and drops by turning
counter clockwise.
Note: adjustment of the minimum output is done at the same
time as the nominal output setting.
In fact, the modulating control board automatically adjusts fan
speed so as to maintain the modulation range up to a minimum
output of 4000 kcal/h (VICTRIX Zeus 20) and 5298 kcal/h
(VICTRIX Zeus 27).
Air-gas ratio adjustment (off-set).
Correct air-gas ratio adjustment (1:1) is done in the factory
and must be reset only when carbon dioxide (CO2) values
are found in the fumes that do not correspond to optimum
values.
For this purpose, during the initial inspection or after ex-
traordinary maintenance jobs, a fumes analysis must be
performed at maximum output and at minimum output
that certifies combustion complies with the values indicated
in the following table:
VICTRIX Zeus 20
VICTRIX Zeus 27
G 31
G 30
G 20
CO2 at nominal
output
CO2 at minimum
output
9,0% ± 0,2
11,7% ± 0,2
10,2% ± 0,2
9,3% ± 0,2
12,2% ± 0,2
10,3% ± 0,2
G 31
G 30
G 20
CO2 at nominal
output
CO2 at minimum
output
9,0% ± 0,2
11,9% ± 0,2
10,0% ± 0,2
9,2% ± 0,2
12,5% ± 0,2
10,6% ± 0,2

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Technical Documentation
To check correctly and if necessary adjust the air-gas ratio,
proceed as follows:
- start the boiler in the chimneysweep mode and adjust the
heating output trimmer on the modulating control board
at minimum (see modulating control board operation).
- perform a combustion product sampling by inserting the
test probe as far as it will go.
- check to see if the carbon dioxide (CO2) value is within the
limits indicated in the table (previous page).
- if the values are incorrect, restore them to within the limits
by means of the gas valve’s off-set setscrew (3) which can be
accessed after having removed the protection cap.
- move the heating output trimmer to maximum and check
the measured carbon dioxide (CO2) reading with that indi-
cated in the table for nominal output (previous page).
Gas conversion.
e appliance can be adapted to a type of gas different to that
for which the boiler is factory set by using the special kits
(natural gas or LPG).
Transformation involves replacing the gas nozzle positioned at
the inlet of the Venturi pipe and regulating the maximum heat
output (see nominal and minimum heat output adjustment).
Finally, check the carbon dioxide (CO2) value at maximum
and minimum output and if necessary adjust by means of the
off-set signal (see air-gas ratio adjustment).
Legend:
1 - Gas valve inlet pressure point
2 - Gas valve outlet pressure point
3 - Off-set setscrew
Honeywell VK 4115 V valve

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Technical Documentation
Technical Documentation
Draught diverter (1).
is is connected to the back of the condensation module and
conveys the combustion products to the exhaust pipe at the
top of the appliance.
It is involved in the transit of the fumes and the condensation
water that has formed inside or in the exhaust pipes.
It is made of plastic resistant to the corrosive effects of
condensation and is suitable for working at a temperature of
up to 130 ºC (max fumes temperature with 85°C delivery =
78 °C).
(from the serial number 2753798 for VICTRIX Zeus 20)
(from the serial number 2731813 for VICTRIX Zeus 27)
Upon the condensation module a fume thermostat (12) is
inserted as safeguard of the draught diverter (1) and intervenes
when the temperature sensed on the condensation module
exceeds 100° C.
Condensation runoff syphon
(See VICTRIX).
Venturi pressure points (P1-P2)
(See VICTRIX).
Air/fume sampling trap
(See VICTRIX).
Fumes circuit.
Operation.
Operation of the fan positioned at the inlet of the air-gas mix
duct ensures the forced extraction of the fumes produced by
the cylindrical burner (5).
ey directly cover the 4 (VICTRIX Zeus 20) or 5 (VICTRIX
Zeus 27) elements of the primary exchanger fitted in the sealed
combustion chamber (6) on the bottom of which is a steel plate
(7) that separates it from the condensation chamber (2) and
deviates the flow of fumes outside the module.
In this way, the exhaust gases, before entering the condensa-
tion chamber (2), cover the 5th (VICTRIX Zeus 20) or 6th
(VICTRIX Zeus 27) element (3) of the exchanger inside which
the primary circuit return water flows.
is cools the products of combustion even more and fa-
cilitates condensation before exiting through the draught
diverter (1).
e condensation water that forms inside the exchanger, in
the draught diverter and possibly in the extraction ducts, flows
down to the bottom of the module from where, before being
drained off, it is conveyed to a syphon (4).
Gas
Air
Condense
draining
Exhaust fumes
1
12

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Technical Documentation
Technical Documentation
Suction and exhaust systems.
(see suction and exhaust terminal instructions).
Boiler generators with condensation technology must be
installed using the new and specific series of suction and
exhaust pipes conceived for use only with the Immergas
condensation boilers.
e boiler can be installed with a fan-assisted sealed chamber
configuration (type C) or the fan-assisted open chamber con-
figuration (type B23).
e fume fittings of the “GREEN SERIES” are made of plastic
material (PPS =self-extinguishing polypropylene) suitable for
resisting the corrosive action of acid condensation.
Fan-assisted open chamber configuration (type
B23) for indoor installation.
Using a specific kit, the VICTRIX Zeus boilers can work in
the fan-assisted open chamber configuration (B23) whereby
combustion air is taken directly from the room.
Suction.
Suction occurs using the hole at the top of the sealed chamber
on which, after having put the relative seal in place (1), the
suction terminal is fitted (2).
e terminal is then secured with the 4 screws (3).
Exhaust.
Connection to the 80 mm diameter exhaust pipes is by means
of the flange used for split systems.
By using the relative accessories we can have either a vertical
or horizontal exhaust.
Maximum permitted length (both vertically and horizontally)
is 30 m.
Fan-assisted sealed chamber configuration
(type C).
Exhaust.
Connection to the exhaust pipes is through a flange (1) or
flanged curve to connect to fitting (2) on the top of the sealed
chamber, placing a specifically shaped seal in between (3).
e flange differs according to whether the system is used split
or concentric.
In the first case, the passage for suction of combustion air (5)
is closed while in the second case it is used.
Suction.
Using the split system, connection to the suction pipes is
exactly the same way as for the exhaust pipes, connecting to
one of the two 80 mm diameter holes (4) at the top of the
sealed chamber.
If coaxial pipes are used, suction occurs by using the concentric
hole outside the exhaust pipe (5).
Suction and exhaust kits.
e kits with relative accessories permit use of two concentric
systems, a split system and two specific systems for ducting
(60 Ø rigid or 80 Ø flexible).
As regards the load losses relating to each accessory and the
various possible combinations see the instructions concerning
the suction and exhaust end pieces.
e coupling of the various accessories (curves, extensions, end
pieces) are the slot type and sealing is ensured by EPDM per-
oxide lip seals resistant to the action of condensation.