Immergas CAESAR 14 Star Guide

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CAESAR STAR
Instantaneous wall-hung room
sealed fan-assisted water heater.
CAESAR 14 Star
General features.
CAESAR Star is a room-sealed water heater featuring
an electronic flame modulation system for regulating
the temperature thanks to a microprocessor-controlled
modulation board and flow and temperature sensors.
CAESAR 14 Star features standard electronic burner
ignition and a wet combustion chamber copper
e changer.
Notwithstanding its very compact size, the appliance
has a power of 21,000 Kcal/h (24.4 kW) corresponding
to a flow of 14 l/min with ∆T 25°C.
CAESAR 14 Star is factory set for connecting to the
broad range of couple-on aspiration and e haust kits
with silicone seals and, thanks to a special cover kit
(optional), it can be installed in open chamber and fan-
assisted configuration (B22). Another optional feature
is an antifreeze safety device that protects it against
temperatures as low as -15°C.

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Main dimensions.
Key:
U - domestic hot water outlet
G - as supply
E - d.h.w. inlet
V - power connections
)mm(thgieH)mm(htdiW)mm(htpeD
036573052
snoitcennoC
SAGRETAWTOHCITSEMOD
GUE
"4/3"2/1"2/1

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CAESAR Star main component parts.
Key:
1 - Sealed chamber
2 - Fume expulsion fan
3 - D.h.w. exchan er
4 - I nition/detection low electrode
5 - Gas valve
6 - D. h. w. NTC probe
7 - Fan safety pressure switch
8 - Overheat. safety thermostat
CAESAR Star Control anel.
Key:
1 - Bathroom water heater stop red indicator
li ht
2 - Flame yellow indicator li ht
3 - Operation switch: 0/ (Reset) and on
temperature switch
9 - Flow limiter
10 - 10 bar safety valve / one way valve
11 - Flow meter
12 - Drau ht diverter.
13 - Combustion chamber
14 - Burner
15 - D.h.w. limit thermostat
16 - Cold water inlet cock

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Hydraulic circuit.
Key:
1 - Fume extraction fan
2 - Sealed chamber
3 - Exchan er
4 - Main burner
5 - Gas valve
6 - D.h.w. adjustment NTC probe
7 - Overheat. temp. safety thermostat
8 - Air pressure switch
9 - Drau ht diverter
10 - Exchan er safety thermostat
11 - Flow limiter
12 - 10 bar safety valve
13 - One way valve
14 - Flow meter
15 - Water inlet filter
16 - D.h.w. inlet cock
U - D.h.w. outlet
G - Gas supply
E - D.h.w. inlet

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Hydraulic circuit.
The hydraulic circuit with relevant control and safety
devices is engaged every time there is a request for
domestic hot water.
Operation.
Drawing at least 2.5 l/min of domestic hot water means
a flow of cold water inside the flow measuring device
(14) and consequent enabling of operation.
Following this, the adjustment circuit ignites the burner.
This way the heat generated by the flame and con-
tained in the fumes produced by combustion is
absorbed by the copper blades of the water-gas
e changer (3) which in turn transfers the heat to the
water flowing inside.
Exchanger.
This is a water-gas e changer (1) with pipes and flaps
in copper at the e it of which is positioned the
overheating safety thermostat (2).
It is of the so-called “wet chamber” type because the
lower part (3) around which is wrapped the hot water
outlet pipe (4), represents in fact the combustion
chamber.
NOTE: to maintain the characteristics of efficiency of
the e changer, we recommend installing a
“polyphosphate dosing” kit if the water is such as to
have characteristics that could create scale on the
pipes (recommended when water hardness exceeds
25 French de rees).
Safety devices and controls.
Flow meter (1).
This is a rotating magnetic sensor fitted at the cold
water flow inlet.
By means of a three-pole connector (2) it is electrically
connected to the adjustment board, allowing this to
measure the flow of water to determine minimum
ignition value (2.5 l/min) and optimise temperature
adjustment.
10 bar safety valve unit (1).
Prevents safety pressure (10 bar) being e ceeded in
the hydraulic circuit of the water heater.
It is connected to the cold water inlet pipe.
Inside is a 10 l/min flow limiter (2) and a one way valve
that prevents the return of hot water towards the mains
supply.

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The circuit consists of an atmospheric burner and a
modulating type valve for gas combustion and gas flow
adjustment respectively.
Operation.
When the main coils (3) are energised, both inner val-
ve shutters open, allowing the gas to flow towards the
burner.
The flow rate/outlet pressure is regulated by means of
the gas valve stabiliser and the modulation coil (1).
By means of the burner nozzles (6), the fuel is injected
into the venturi pipes (ramps) inside which the air-gas
mi is obtained that is ignited by the spark from the
ignition electrode (5).
Modulating gas valve.
The gas valve (SIT 845) features two main coils (3)
and a modulation coil (1) controlled by the modulation
board.
The ma imum and minimum outlet pressure settings
can be made on this valve (see as adjustments).
Main electrical coils (3).
Two coils of the ON-OFF type energised (230V AC)
by the adjustment board when the burner has to be
ignited.
These are electrically connected in parallel and
energised by mains power through a special connec-
tor (2).
Modulation coil (1).
This is a low-voltage coil controlled by the modulation
board.
This controls the gas valve stabiliser and permits
changing the outlet pressure in a way proportionate to
the DC signal that runs through it.
Gas circuit.
Burner.
The burner consists of 12 horizontal venturi pipes (4)
in which the gas is injected by an equal number of
nozzles (6) mounted on the special header (7).
Ignition occurs by means of the adjustment board which
controls the ignition/detection electrode (5).
Ignition and detection electrode (5).
During ignition, this is controlled by the adjustment
board which produces an electrical charge between
its end and the burner surface that ignites the air-gas
mi .
When the burner is on, it also detects the flame on the
burner enabling the adjustment board to conclude the
ignition cycle and change the gas pressure according
to need.
This is positioned on the front of the burner in line with
the centre ramp.

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Gas adjustments.
Ma and minimum gas pressure adjustments can be
made by means of the gas valve respecting the values
shown on the tables relating to the type of
corresponding gas.
Measurements are made using a U-shaped differen-
tial pressure gauge connected to a “Y” to be placed in
between in the small silicone tube connecting the gas
valve to the sealed chamber and to the gas valve outlet
pressure point.
Valve Sit 845.
Maximum pressure setting.
Draw d.h.w. after setting the temperature switch at
ma imum.
Turn the brass nut (3) clockwise to increase the
pressure to the burner and anticlockwise to decrease
it.
Adjusting minimum pressure
(to be done after adjusting max pressure).
After interrupting power to the modulation coil, turn the
crosshead screw (2) clockwise to increase pressure
to the burner and anticlockwise to decrease pressure.
Key:
1 - Coil
2 - Minimum output setscrew
3 - Maximum output setscrew
4 - Gas valve outlet pressure point
5 - Gas valve inlet pressure point
6 - Protection cap
Valvola Sit 845
Changing type of gas.
Adaptation to a type of gas different to that for which
the boiler is intended, can be done by using the special
kits (natural as or LPG).
The changeover consists in replacing the burner
nozzles and in moving to the modulation board of the
“NATURAL GAS- LPG” (S1) bridge.
The minimum and ma imum pressures are then set
on the gas valve in the way described above.
The burner ignition pressure is not adjusted
because the type of board operation does not require
such setting (see modulation board operation).
NOTE: any changes made to enable the unit to use
G110 gas (town as), besides the use of a special
nozzle kit and performance of the same operations
indicated above, also requires shifting jumper switch
“S1” onto switch “S2” on the electronic board (see
modulation board adjustments).

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Operation.
The products of combustion, after investing the water-
gas e changer (3), are conveyed to a draught diverter
(5) on top of which the fume e tractor (fan) (1) is fitted.
Fan operation ensures forced e pulsion of the fumes
and, at the same time, creates a vacuum in the sealed
chamber (2) so the combustion air can be e tracted
from outside.
Correct fume e traction is controlled by a special
pressure switch (4), the operation of which enables or
prevents the burner from igniting.
Fume pressure switch (4).
Positioned in the top inner part of the sealed chamber
and detects, by means of special pressure points, the
difference in pressure between the top of the draught
diverter (the point where the extractor is positioned
and operates) and the inside of the sealed chamber.
Operation of this switch causes a microswitch (S3) to
close. This affects the adjustment board and either
enables or prevents burner ignition.
Fan (1).
The e tractor operates downstream of the combustion
chamber and is fitted vertically in the top part of the
draught diverter (5) from which it e tracts the fumes
and conveys these into the e haust pipes to which the
boiler is connected.
Fume circuit.
It is controlled by the adjustment board and its
operation coincides with that of the burner.

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Extraction and exhaust systems.
The CAESAR Star is set for connecting to the coupling
e traction/e haust ducts and can be installed in sealed
chamber fan-assisted configuration (type C) or, thanks
to a special kit, in open chamber fan-assisted version
(type B22).
As regards the load losses relating to each accessory
and the various possible combinations and the use of
diaphragms to be fitted according to the length of the
pipes, see instructions relating to extraction and
exhaust ends (CAESAR Star instruction booklet).
Accessories (bends, extensions and end pieces) are
joined by coupling and seal is provided by special
silicone lip seals.
Open chamber and fan-assisted (type
B22) configuration for installation
outdoors in a partially protected area
(see illustration alongside).
Using a special cover (4) to be placed on the top part
of the sealed chamber, the CAESAR Star appliance
can be fitted in a partially protected place.
This way the appliance works in open chamber and
fan-assisted (B22) configuration.
Extraction.
To fit the cover (4), the two caps (1) that close the
holes in the top part of the sealed chamber must be
removed.
The e traction of comburent air is done directly from
the environment e ploiting the free space between the
lower part of the cover (4) and the upper part of the
boiler.
Exhaust.
The 80 mm diameter union to the e haust ducts is
obtained by means of a flange (3) used in doubled
systems.
The use of special accessories permits horizontal type
(A) or vertical type (B) e haust.
To avoid condensation problems, the e haust duct
must be restricted to 5 metres for normal pipes and
12 metres for insulated pipes.

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Sealed chamber fan-assisted
configuration (type C).
Exhaust.
Connection to the e haust pipes is by means of a
flange (1) or a flanged bend to be fitted on the centre
hole (6) on the top section of the sealed chamber,
placing in between a special shaped seal (5).
This flange differs according to whether the doubled
or concentric system is used.
In the former case, the duct for the combustion air (8)
is closed, while in the latter case it is used.
To ensure correct boiler operation, a diaphragm (7)
will have to be fitted on the e haust pipe (6) between
the flange used (1).
Diaphragms are envisaged of different diameter which
must be fitted according to the type of duct and its
length (see CAESAR Star instruction booklet).
Extraction.
Using the doubled system, connection to the e traction
ducts is done in the same way as for the e haust pipes,
linking up to one of the two holes with diameter 80 mm
(2) on the top section of the sealed chamber.
The hole which is not used is closed using one of the
caps (3), placing in between the relevant seal (4) fea-
tured on the appliance.
If coa ial pipes are used, e traction is done by e -
ploiting the concentric hole outside the e haust pipe
(8).
Extraction and Exhaust Kits.
The kits with the relevant accessories make it possible
to use two concentric systems and a doubled
system.As regards flow resistance relating to each
accessory, the various possible combinations and use
of the diaphragms to be installed according to the
length of the ducts, see the instructions relating to the
e traction and e haust ends (CAESAR Star
instruction booklet).
The accessories (bends, extensions and end pieces)
are connected by means of slot-in couplings and seal
is ensured by means of silicone-lip seals.
Horizontal concentric slot-in kit Ø 60/100.
The e haust pipe (Ø 60 mm) is fitted inside the
e traction pipe (Ø 100 mm).
Connection to the boiler is by means of a 90° (2) fully
adjustable bend which, by means of the necessary e -
tensions, must be connected to the e traction and e -
haust end piece (3).
The ma imum overall length allowed beyond the first
bend (2) is 3 straight horizontal metres.

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Vertical concentric slot-in kit Ø 60/100.
The e haust pipe (Ø 60 mm) is fitted inside the
e traction pipe (Ø 100 mm).
Connection to the boiler is by means of a flange (2)
which, by means of the necessary e tensions, must
be connected to the e traction and e haust end piece
60/100 (5) with aluminium tile.
The ma imum overall length allowed is 4.7 straight
vertical metres.
Ø 80/80 slot-in separator kit.
The pipes both have a diameter of 80 mm.
Connections to the boiler are by means of two special
flanges for e haust (4) from central union and e trac-
tion (3) from one of the two side holes.
The ma imum length allowed (e traction + e haust)
is 33 straight horizontal metres and 41 straight ver-
tical metres.
To avoid problems of condensation, the e haust pipe
should be restricted to a max of 5 m.
E traction
E haust

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Electrical circuit.
The electrical circuit of the CAESAR Star appliance is
fully controlled by an electronic modulation board which
controls all generator functions and to which are
connected the electrical devices of the appliance.
230 V AC circuit.
Safety devices and controls.
Some of the control and safety devices operate at
mains voltage and others at low voltage.
Key:
B1 - D.h.w. NTC probe
B2 - Flow measurer
E1 - I ntion/detection low electrode
E2 - Linit thermostat
E3 - Overheat.safety thermo
H1 - Flame presence LED
H2 - Fault indicator LED
Y1 - Gas valve
Y2 - Modulator coil
M1 - Fan
S1 - Natural/LPG as switch
S3 - Fume pressure switch
S4 - Master switch (D.h.w. adjuster)
F - Fuse
This detects ignition of the burmer by whose flame it is invested.
It is connected to the ignition/detection circuit of the adjustment board.
The electrode also works as an ignition glow electrode.
Detection electrode
(E1)
This interrupts power to the circuit when power input is
over 2 A. It is fitted on the modulation board.
Fuse Fuse 2 AF
250 V
When the safety temperature is e ceeded (100 ºC) this
interrupts power to the main coils of the gas valve (Y1).
It is located at the e changer outlet.
Overheating safety
thermostat
(E3)
Two-contact
clicson
thermostat
When the safety temperature is e ceeded (85 ºC) this
interrupts power to the main coils of the gas valve (Y1).
It is located on the d.h.w. e it pipe.
D.h.w. limit thermostat
(E2)
Two-contact
clicson
thermostat
Blue
Brown
Yellow/green
White
White
Blue
Brown
Blue
Brown
Black
Red Red
Black
Black
Black
Red
Black
Orange
F
S4
ON/OFF
D.H.W. Adjust.
Primary
Secondary
Antifreeze kit
power supply
230Vac
50HZ
power
supply

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Loads.
Low-voltage circuit.
Safety devices and controls.
Loads.
This is controlled by the ignition circuit of the adjustment board which provokes
an electric spark between its end and the burner surface that ignites the air/
gas mi .
The electrode also acts as a detection glow electrode.
Ignition Electrode
(E1)
This is powered by the ignition circuit of the adjustment board when the burner
has to be ignited.
Permits flow of gas to the burner.
Gas valve
(Y1)
Ensures the flow of air inside the sealed combustion chamber and the e it of
fumes produced by combustion.
Powered by the adjustment board.
Fan
(M1)
Depending on position, permits:
0 + RESET: low-voltage circuit not powered and release
after tripping of no ignition or overheating safety device.
On + D.h.w. temperature: low-voltage circuit powered and
d.h.w. temperature adjustment.
Master switch
(D.h.w. adjuster)
(S4)
On-Off switch
+
Trimmer
This is a magnetic sensor that measures the flow of d.h.w. It is fitted at the cold
water inlet.
It is connected to the adjustment board enabling this to detect the minimum
flow for burner ignition (2.5 l/min) and optimise the hot water temperature
adjustment.
Flow measuring device
(B2)
This affects the adjustment board, enabling the ignition
circuit and then burner operation when the fan ensures
correct fume e traction.
When closed with fan off, does not enable start of ignition
cycle.
Fume pressure switch
(S3)
Double-contact
switch
This is powered by the modulation board with variable continuous current.
Permits changing gas pressure to burner.
Modulator coil
(Y2)
This enables the modulation board to detect the outlet tem-
perature of the d.h.w.
Its breakage stops burner operation.
It is fitted in the d.h.w. pipe at the e changer e it.
D.h.w. NTC robe
(B1)
NTC Sensor
10 kohm 25 °C

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CAESAR Star electrical circuit.
Operation.
When master switch (S4) is in ON position, it powers
the low-voltage circuit and enables appliance
operation.
If hot water is run the flow measuring device (B2) trips
and this gives the signal for burner ignition.
Afterwards, if the temperature detected by the d.h.w.
NTC sensor (B1) is below that set on the control panel
by means of the d.h.w. potentiometer (S4) the board
starts the fan (M1) and commands relay K1.
The consequent closing of the fume pressure switch
(S3) results in the adjustment circuit powering relay
K2.
This way the board ignition circuit is enabled (IGNITION
SECTION) which first of all commands the ignition/
detection electrode (E1) and then e cites relay K3.
With a signal from the overheating thermostat (E3) and
limit thermostat (E2), closing of relay K3 contact powers
both main coils of gas valve (Y1).
Burner ignition is detected by ignition/detection
electrode (E1).
IGNITION
SECTION
COMMAND LOGIC MICROPROCESSOR
MAINS
VOLTAGE LOW
VOLT.

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Modulation board.
Inside the CAESAR Star control bo is a
microprocessor controlled electronic board that
integrates ignition and adjustment functions and, by
Operation.
When the master switch (S4) is in ON position it powers
the low-voltage circuit and enables appliance
operation.
If hot water is run the flow measuring device (B2) trips
and this gives the signal for burner ignition.
Afterwards, if the temperature detected by the d.h.w.
NTC sensor (B1) is below that set on the control panel
by means of the d.h.w. potentiometer (S4) the board
starts the fan (M1) and commands relay K1.
The consequent operation of fan (M1) results in closing
of fume pressure switch contact (S3) thereby allowing
the adjustment circuit to e cite relay K2.
This way the board ignition circuit is enabled which
first of all commands the ignition electrode (E1) and
then, by means of relay K3, the main coils of gas val-
ve (Y1).
During the ignition phase, the power to the modulation
coil is gradually taken, in just 8 seconds, from minimum
to 50% of ma imum.
Afterwards, the signal is increased so as to immediately
reach (if required) the ma imum value set on the gas
valve.
During operation, flame modulation occurs with
reference to the difference between the temperature
set with the d.h.w. potentiometer (d.h.w. adjustment)
means of LEDs, shows the operating condition of the
appliance, indicating any tripping of safety devices.
and the temperature read by the d.h.w. NTC probe
(B1).
When the set value is e ceeded, the burner is kept
running at the minimum d.h.w. power (6, kcal/h)
and the contact of the relay K2 is opened (burner off)
only when the d.h.w. NTC probe (B1) reads a tempe-
rature above 66°C whatever the set temperature.
In this situation, the burner is turned on and off with
variable frequency in a way inversely proportionate to
the flow of water read by the flow measuring device in
order to keep the temperature constant.
If the water temperature drops below 54°C or a
considerable variation in flow is detected (about 1l/min),
burner ignition and switchoff occur with reference to
the temperature read by the d.h.w. NTC probe instead
of to the flow of water.
The modulation range (maximum and minimum)
during operation is regulated on the gas valve (see
gas adjustments).
FUSE
Primary
Secundary
IGNITION TRANSF.
NATURAL
GAS / LPG
ON/OFF
D.H.W. ADJ.
MICROPROCESSOR
TOWN
GAS

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Enables the ignition circuit of the board to detect the presence of a flame on
the burner. If this does not operate, the no ignition lock trips, signalled by the
lighting up of red LED H2.
Any operation prior to burner ignition is indicated by the flashing of red LED
H2.
Ignition/Detection
electrode
(E1)
Inputs.
Integrated in a single device.
- an On/Off switch that permits powering the board and resetting after a safety
device has tripped.
- a potentiometer which only when in “ON” position permits adjustment of the
water temperature between 40° and 60°C.
Master switch
(d.h.w. adjustment)
(S4)
This provides power to the gas valve when fan operation
ensures correct fume e traction.
If this is closed with the fan off, it does not enable ignition
cycle start.
Fume pressure switch
(S3)
Open =
Fan Off
Closed =
Fan On
This is a resistance that varies in a way inversely
proportionate to the d.h.w. outlet temperature.
D.h.w. NTC probe (B1) NTC Sensor
10 kohm 25 °C
When the safety temperature is e ceeded (100 ºC) this
interrupts power to the main coils of the gas valve (Y1).
The tripping of this device stops boiler operation
(overheatin stop) and is indicated by the flashing of red
LED H2.
Overheat. safety
thermostat
(E3)
Two-contact
clicson
thermostat
When the safety temperature is e ceeded (85 ºC) this
interrupts power to the main coils of the gas valve (Y1).
Its operation stops boiler operation and is indicated by the
flashing of the red LED H2.
D.h.w. limit thermostat
(E2)
Two-contact
clicson
thermostat
This is a magnetic sensor that changes its rpm in a way proportionate to the
flow of d.h.w.
It is connected to the adjustment board enabling this to detect the minimum
flow for burner ignition (2.5 l/min) and optimise the hot water temperature
adjustment.
Flow measuring device
(B2)

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Outputs.
This is a positive square-wave signal with variable ON-OFF ratio (duty-cycle)
that controls the modulation coil of the gas valve and makes it possible to alter
gas pressure to the burner.
Modulator coil
(Y2)
This is a high voltage signal (about 16 kV) for energising the ignition electrode
on the boiler.
Ignition/Detection
electrode
(E1)
This is a single-pole relay which is e cited when the burner has to be ignited.
By means of its contact, the adjustment board ignition circuit is controlled.
Request Relay
(K2)
This is a single-pole relay that is e cited by the ignition circuit to energise the
main gas valve coils (Y1).
Gas Valve relay
(K3)
This is a single-pole relay for controlling the fan (M1) which is e cited when
operation is required.
Fan Relay
(K1)
Adjustments.
For setting the temperature of the doemstic hot water for heating between
40°C and 60°C.
Master Switch
(d.h.w. adjustment)
(S4)
Depending on its position (Natural as/LPG), it adapts the
modulation parameters for the gas for which the appliance
is set.
Gas switch
(S1)
Gas switch G110
(S2)
For adapting the modulation parameters of the board to
gas G110 (town as).
Engaged using the jumper on gas switch S1 which must
be shifted onto switch S2.
Absent = Natural
gas
Present = LPG
Absent = Natural
gas or LPG
Present = G110
(with S1 absent)

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Safety devices.
If, within 10 seconds from the start of the ignition cycle, the detection electrode
(E1) fails to detect the presence of a flame on the burner, appliance operation
is stopped.
To start the appliance again, the master switch (S4) will have to be moved to
OFF and afterwards, after returning the switch to ON, the hot water will have to
be run.
The tripping of the safety switch is indicated by the lighting up of red LED H2.
No ignition stop
In the event of the overheating thermostat contact (E3) and limit thermostat
being opened, the appliance is stopped.
To start the appliance again, the master switch (S4) will have to be moved to
OFF position and afterwards, after returning the switch to ON, the hot water
will have to be run.
The tripping of the safety device is indicated by the flashing of red LED H2.
Overheating stop
After the burner has switched off, at the end of a request, the combustion
chamber is washed and the fan (M1) is kept running for 30 seconds.
Sealed chamber post
ventilation
Breakage of sensor B1 prevents the appliance for working.
The tripping of the safety device is indicated on the control panel by flashing of
yellow LED H1.
Breakage of NTC
sensor
(B1)
Depending on their condition, these indicate:
H2 H1
(red led) (yellow led)
water heater off or no operation request
off off
water heater in stand-byoff flashing
presence of flameoff on
fume pressure switch fault or no airsimultaneous flashing
Indicators.
ignition failure stopon off
overheating stop
intermittent off
flashing
NTC probe fault
off intermittent
flashing

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CAESAR Star operation sequence.
ower on
Master switch (S4) in ON position.
ower circuit adjustment
The closing of master switch (S4) powers the modulating board and enables operation.
Detection of d.h.w. request (Flow measuring device)
Running of d.h.w.



Ignition circuit power
If the temperature of the d.h.w. is below that set, the adjustment circuit of the board powers the ignition
circuit.
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Exhaust flue pressure switch contact control
The board determines the correct position of the e haust flue pressure switch (contact normally open N.O.)
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power
The board powers the fan.
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Exhaust flue pressure switch contact control
The board determines the closing of the e haust flue pressure switch following fan operation
(contact normally closed N.C.)
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Ignition electrode power
The ignition circuit of the board powers the ignition electrode (E1).
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Gas valve coil power
The board powers the gas valve coils (Y1) and sends the slow ignition signal to the modulating board.
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Burner ignition (slow ignition)
The board conveys slow ignition power to the modulating board (Y2).
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Flame detection
By means of the ionisation electrode (E1) the unit detects burner ignition and ends the ignition cycle.
Appliance working
The burner operates at a power that varies according to the adjustments made and the temperature and
flow detected by the sensors.
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20
STCS ed 07/02 CAESAR Star
Technical Documentation
Technical Documentation
Technical details.
CAESAR Star technical details.
- The e haust flue temperature values refer to
incoming air temperature of 15°C.
- The data relating to the d.h.w. supply refer to a
dynamic inlet pressure of 2 bar and an incoming tem-
perature of 15°C; these values are read immediately
at the water heater outlet considering that to obtain
the declared values mi ing with cold water is
required.
- The combustion details refer to a thermal power
below 15°C and to a pressure of 1013 mbar.
Nominal heat output
Minimum heat output capacity
Nominal heat output (working)
Minimum heat output (working)
Working thermal efficiency at nominal output
Loss of heat at casing with burner on
Loss of heat at chimney with burner on
kW (kcal/h)
kW (kcal/h)
kW (kcal/h)
kW (kcal/h)
%
%
%
27,6 (23730)
8,9 (7689)
24,4 (21000)
7,0 (6000)
88,5
3,5
8,0
G20 G30 G31
Diameter of nozzles
Supply pressure
mm
mbar (mm H
2
O)
1,30
20 (204)
0,77
29 (296)
0,77
37 (377)
Water content of generator
D.h.w. adjustable temperature
Flow limiter
Min. pressure (dynamic) ON burner (up)
Min. pressure (dynamic) ON burner (down)
Min flow (dynamic) ON burner (up)
Min. flow (dynamic) ON burner (down)
Ma operating pressure of d.h.w. circuit
Continuous service drawing capacity (∆T 25 °C) in mi ing
Continuous service drawing capacity (∆T 50 °C)
Full boiler weight
Empty boiler weight
l
°C
l/min
bar
bar
l/min
l/min
bar
l/min
l/min
kg
kg
1,0
40-60
10
0,25
0,20
2,5
2,0
10
14
7
23
22
Power connection
Nominal input
Installed power
Power absorbed by fan
Appliance electrical system cutout
V/Hz
A
W
W
-
230/50
0,25
50
35
IPX4D
G20 G30 G31
Nominal power e haust flue mass flow
Minimum power e haust flue mass flow
CO
2
at nominal/min power
CO at 0% of O
2
at nominal/min power
E haust flue temperature at nominal power
E haust flue temperature at minimum power
kg/h
kg/h
%
ppm
°C
°C
64
68
6,10/1,75
21/94
126
86
68
70
6,60/2,00
38/132
124
85
69
72
6,50/1,90
30/136
125
84