Page 1
Appr. Nr. A 9504 A • 0085 AQ 0766
RENDIMAX N EL
gas-fi red cast iron boiler for central heating
with elec tron ic ignition and fl ame control
OPERATING, IN STAL LA TION AND MAINTENANCE INSTRUCTIONS
cod. 3543742/3 - 05/2005
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Warning
• Read the warnings given in this manual thor ough ly. They provide important information for
safe installation, use and maintenance
• Keep the manual carefully for future con sul ta tion.
• The instruction manual is an integral and es sen tial part of the product and must be kept
by the user.
• If the appliance is sold or transferred to another
owner or if the owner moves, leaving the ap pli ance behind, always ensure that the manual
is kept with the appliance for consultation by
the new owner and /or installer.
• Incorrect installation or poor maintenance
ab solves the manufacturer from all liability for
damage to people or things.
• Installation and maintenance must be carried
out i conformity with current legislation, ac cord ing to the manufacturer’s instructions and
by qualified personnel.
• Before cleaning or maintenance, disconnect the
appliance from the mains via the switch on the
appliance or a suitable isolating device.
• In the event of malfunction or faulty operation,
deactivate the appliance. Do not attempt to
repair or carry out any other operation on the
appliance directly. Contact qualified personnel
only.
• Repairs or the replacement of components must
be carried out exclusively by qualified personnel using original spare parts only. Fail ure to
respect the above my compromise the safety
of the appliance.
• To guarantee efficient operation, the appliance
must be serviced once a year by an authorised
service centre.
• The appliance may not be used for purposes
other than those for which it was explicitly designed. Any other use is considered im prop er
and therefore dangerous.
• Incorrect installation and use or failure to follow
the instructions provided by the manufacturer
absolve the manufacturer from all liability for
damage.
• After unpacking, check that the contents are
whole and undamaged.
• Keep packing out of reach of children as it is
potentially hazardous.
• To clean external parts, use a damp cloth mois tened with soapy water if necessary. Avoid using
abrasive cleaning products and solvents.
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INDEX
OPERATING INSTRUCTIONS
1. Description of the boiler....................................................................................................................... 5
2. Main components ................................................................................................................................. 6
3. Ignition and shut-down......................................................................................................................... 7
4. Checks and maintenance...................................................................................................................... 8
INSTALLATION AND MAINTENANCE INSTRUCTIONS
5. Description of the boiler....................................................................................................................... 9
6. Main components ............................................................................................................................... 10
7. Technical specifications ...................................................................................................................... 11
8. Installation and safety devices............................................................................................................ 16
9. Electrical connections ......................................................................................................................... 18
10. Set-up................................................................................................................................................ 20
11. Settings............................................................................................................................................. 21
12. Gas conversion ................................................................................................................................. 23
13. Checks and maintenance.................................................................................................................. 24
14. Troubleshooting ............................................................................................................................... 26
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OPERATING INSTRUCTIONS
1. DESCRIPTION OF THE BOILER
1.01 Presentation of the boiler
The “Rendimax N EL” floor-standing boilers are gas-fired heat generators for central heating systems, with castiron bodies.
They are fitted with electronic ignition devices, automatic operation control (electronic flame control unit) and flue
gas sensors for verifying the correct discharge of the combustion gases.
The “Rendimax N EL PV” models are also pre-fitted with a variable-speed pump, expansion vessel and safety
valve.
The boilers are manufactured as standard for operation on natural gas (G20); For operation on LPG (G31), the
boilers must be converted on-site.
1.02 Instructions and requirements
The assembly, installation, conversion to other type of gas, commissioning and maintenance of the boiler must be
performed by specialist Companies, following all the relative technical requirements and standards. The boiler must
be installed according to the Standards and Laws in force, in particular regarding the size of the boiler room, the
discharge of flue gases, the water piping, the combustible gas supply system and the electrical system.
1.03 Checking and controlling the discharge of fl ue gases
The boiler is fitted with a flue gas thermostat, which cuts off the supply of gas to the burner in the event of incorrect functioning of the flue.
If the flue gas thermostat is activated, unscrew the protective cover on the control panel (3, Fig. 1) and press the
manual reset button; the boiler will then re-ignite.
If the flue gas thermostat is activated frequently, shut-down the boiler and call the Service Department.
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2. MAIN COMPONENTS
Fig. 1
Key
1 Boiler thermostat
2 Thermal pressure gauge
3 Flue gas thermostat cover
4 Gas valve
5 Cap (ready for mounting electronic control unit)
6 Drain valve
7 Electrode assembly
8 Control panel
9 Burner assembly
Front view of the boilers with control panel cover open
5 3 11 10
14
15
13
9
6
7
12
8
1
2
4
8
5 3 11 10 1312
10 Boiler switch
11 Reset button for electronic flame control unit
12 Electronic flame control unit
13 Safety thermostat with automatic reset
14 Heating system pump (PV version)
15 Cap on fitting for filling the system (PV version)
Mod. 16-23 PV Mod. 30-36
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3. IGNITION AND SHUT-DOWN
3.01 Ignition
Place the boiler thermostat in the “minimum temperature” position and power the appliance using the boiler
switch.
To ignite the burner assembly, proceed as follows:
• open the gas cock (fitted by the installer);
• adjust, using the knob, the boiler thermostat to the desired value (not less than 50°C.).
At this stage, the electronic control unit starts operating and will pilot, after a set waiting time, the gas valve and
the spark to the ignition electrode, which in turn will light the burner assembly. The ionisation electrode then checks
the presence of the flame in the burner assembly.
The boiler operates automatically, controlled by the boiler thermostat and/or any other control devices (room
thermostat, electronic temperature control unit, etc.).
Note If after having correctly performed the ignition operation, the burners do not light and the reset button light
on the electronic control unit (11 - Fig. 1) is on, wait around 10 seconds and then press the reset button. The
control unit is reset and will repeat the ignition cycle.
Note In the event of power failure, the burners will shut-down and will be automatically ignited once the power
returns.
3.02 Temporary shut-down
To temporarily shut-down the boiler, simply place the boiler switch (10- Fig. 1) in position ”0”.
3.03 Extended boiler shut-down
To shut the boiler down, proceed as follows:
• turn the knob of the boiler switch to position ”0”;
• close the gas cock upstream from the boiler;
• disconnect power to the appliance.
Note If the boiler is not used for an extended period in winter, to avoid damage from frost, special anti-freeze
should be added to the system, or else the system should be completely emptied (operation to be performed
only by qualified personnel).
3.04 Adjusting the central heating supply temperature
The supply temperature can be set using the boiler thermostat. The field of adjustment for the knob (1 - Fig. 1)
is 30-90 °C. It is not recommended to set the temperature below 50°C, to avoid dangerous condensation from
occurring.
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4. CHECKS AND MAINTENANCE
Attention
Current technical standards envisage periodic maintenance of the appliance, as well as analysis of the composition of the flue gas, to check correct combustion in the burner assembly. As a result, it is suggested that the user
stipulate a programmed maintenance contract with a specialised company to periodically carry out the operations
listed below.
4.01 General notes on maintenance
Have the correct operation and integrity of the flue checked periodically.
In the event of work or maintenance on structures located near the flues and/or flue gas discharge devices and
accessories, shut the appliance down and, upon completion of the work, have the condition of such parts checked
by professionally qualified personnel.
Do not clean the appliance and/or its parts with easily inflammable substances (e.g. petrol, alcohol, etc.).
Do not leave containers with inflammable substances in the room where the appliance is installed.
4.02 System checks (to be performed once a year)
The system is generally checked at the end of the winter season. Check that the water in the expansion vessel is
pressurised. Verify serviceability and operation of the pumps.
4.03 Boiler checks (to be performed once a year)
• Check the boiler for correct operation by effecting ignition and shut-down tests using the regulation
thermostat.
• Check on the rear wall of the boiler, at the height of the draught diverter, that there are no flue gas leaks, signs
of any blockages in the flue or insufficient draught.
• Check that the connecting pipe between the boiler and flue is perfectly sealed at the joints.
4.04 Cleaning the boiler and the fl ue
To be performed once every 3 years.
4.05 Cleaning the burner assembly
To be performed once a year.
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INSTALLATION AND MAINTENANCE INSTRUCTIONS
5. DESCRIPTION OF THE BOILER
5.01 presentation of the boiler
The “Rendimax N EL PV” floor-standing boilers are gas-fired heat generators for central heating systems, with
cast-iron bodies.
They are fitted with electronic ignition devices, automatic operation control (electronic flame control unit) and flue
gas sensors for verifying the correct discharge of the combustion gases.
The “Rendimax N EL PV” models are also pre-fitted with a variable-speed pump, expansion vessel and safety
valve.
The boilers are manufactured as standard for operation on natural gas (G20).
The appliance can be converted from operation on natural gas to lpg (G31); refer to the instructions provided in
paragraph 12.
5.02 instructions and requirements
The assembly, installation, commissioning and maintenance of the boiler must be performed by specialist companies, following all the relative technical requirements and standards. The boiler must be installed according to the
standards and laws in force, in particular regarding the size of the boiler room, the discharge of flue gases, the
water piping, the combustible gas supply system and the electrical system.
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6. MAIN COMPONENTS
6.01 main components
Key
1 Boiler thermostat
2 Thermal pressure gauge
3 Flue gas thermostat cover
4 Gas valve
5 Cap (ready for mounting electronic control unit)
6 Drain valve
7 Electrode assembly
8 Control panel
9 Burner assembly
10 Boiler switch
11 Reset button for electronic flame control unit
12 Electronic flame control unit
13 Safety thermostat with automatic reset
14 Hheating system pump (pv version)
15 Cap on fitting for filling the system (pv version)
16 Flue thermostat bulb
17 Smokebox
18 Safety valve (pv version)
19 Expansion vessel (pv version)
fig. 2
5 3 11 10
14
15
13
9
6
7
12
8
1
2
4
8
5 3 11 10 1312
19
18
17
16
Mod. 16-23-30 PVMod. 16-23 PV Mod. 30-36
Front view of the boilers
with control panel cover open
Rear view
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7. TECHNICAL SPECIFICATIONS
7.01 Table of technical specifi cations, dimensions and connections (base version)
Maximum boiler operating temperature 100°c.
Injectors
Natural Gas (G20)
MODEL
Rendimax N 16 EL
Rendimax N 23 EL
Rendimax N 30 EL
Rendimax N 36 EL
Injectors
L.P.G. (G31)
Conections
MODEL
Rendimax N 16 EL
Rendimax N 23 EL
Rendimax N 30 EL
Rendimax N 36 EL
Gas supply
pressure
mbar
Dimensions
Heat output Heat input (NET)
MODEL
Nominal Adjustable up to: Min.Nominal
Rendimax N 16 EL
Rendimax N 23 EL
Rendimax N 30 EL
Rendimax N 36 EL
kW
16,2
23,0
29,5
36,0
kcal/h
14.000
19.800
25.400
31.000
kW
18,0
25,5
32,8
40,0
kcal/h
15.500
22.000
28.200
34.400
kW
12,7
18,4
23,0
27,6
kcal/h
11.000
15.800
19.800
23.800
Number
of
sections
3
4
5
6
Boiler
water
content
lt.
7,3
9,0
10,7
12,4
Max.
working
pressure
bar
6
6
6
6
Ø injector
mm
2,45
2,35
2,35
2,35
Nominal
pressure
mbar
13,0
15,2
14,2
13,5
Ø injector
mm
1,55
1,50
1,50
1,50
Nominal
pressure
mbar
35
35
35
35
Gas flow
rate
L.P.G. G31
kg/h
Natural G20
m
3
S/h
VK 4105C1009
VK 4105C1009
VK 4105C1009
VK 4105C1009
Gas valve
Honeywell
kcal/h
9.500
13.800
17.200
20.600
kW
11,0
16,0
20,0
24,0
Number
injectors
2
3
4
5
Natural
G20
18-20
18-20
18-20
18-20
L.P.G.
G31
37
37
37
37
min.
1,16
1,69
2,46
2,95
nom.
1,94
2,70
3,47
4,23
min.
0,90
1,31
1,63
1,96
nom.
1,50
2,08
2,68
3,27
Return
a1
1"
1"
1"
1"
Flow
a2
1"
1"
1"
1"
Gas
inlet
a3
1/2"
1/2"
1/2"
1/2"
400
400
500
600
A
mm
57
62
72
82
B
mm
33
33
33
58
C
mm
62
24
36
47
D
mm
100
110
130
150
Ø
mm
a1
B
A
Ø
a3
a2
D
D
284
850
660
590
600
C
fig. 3a
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7.02 Table of technical specifi cations, dimensions and connections (pv version)
Maximum boiler operating temperature 100°C
Natural Gas (G20)
MODEL
Rendimax N 16 EL PV
Rendimax N 23 EL PV
Rendimax N 30 EL PV
L.P.G. (G31)
Conections
MODEL
Rendimax N 16 EL PV
Rendimax N 23 EL PV
Rendimax N 30 EL PV
Gas supply
pressure
mbar
Dimensions
Heat output Heat input (NET)
MODEL
Nominal Adjustable up to: Min.Nominal
Rendimax N 16 EL PV
Rendimax N 23 EL PV
Rendimax N 30 EL PV
kW
16,2
23,0
29,5
kcal/h
14.000
19.800
25.400
kW
18,0
25,5
32,8
kcal/h
15.500
22.000
28.200
kW
12,7
18,4
23,0
kcal/h
11.000
15.800
19.800
Number
of
sections
3
4
5
Boiler
water
content
lt.
7,3
9,0
10,7
Max.
working
pressure
bar
6
6
6
Ø injector
mm
2,45
2,35
2,35
Nominal
pressure
mbar
13,0
15,2
14,2
Ø injector
mm
1,55
1,50
1,50
Nominal
pressure
mbar
35
35
35
Gas flow rate
L.P.G. G31
kg/h
Natural G20
m
3
S/h
VK 4105C1009
VK 4105C1009
VK 4105C1009
Gas valve
Honeywell
kcal/h
9.500
13.800
17.200
kW
11,0
16,0
20,0
min.
1,16
1,69
2,46
nom.
1,94
2,70
3,47
min.
0,90
1,31
1,63
nom.
1,50
2,08
2,68
L.P.G.
G31
37
37
37
Natural
G20
18-20
18-20
18-20
Return
a1
1"
1"
1"
Flow
a2
1"
1"
1"
Gas
inlet
a3
1/2"
1/2"
1/2"
Capacità
vaso
espansione
6
6
8
lt.
Valvola
di
sicurezza
3
3
3
bar
400
400
500
A
mm
57
62
72
B
mm
33
33
33
C
mm
62
24
36
D
mm
72
34
46
E
mm
622
622
637
F
mm
100
110
130
Ø
mm
Number
injectors
2
3
4
B
A
Ø
a3
a2
a1
D
E
660
590
510
C
F
850
600
fig. 3b
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7.03 output variability characteristics
The heat rate of the boiler furnace and, as a consequence, the heat output delivered to the central heating water,
can be adjusted by simply adjusting the main burner assembly via the gas valve. The diagrams in figs. 4a and 4b
indicate the variation in heat output delivered to the water in relation to the adjustment of the operating pressure
of the burner assembly. The possibility of adjusting the boiler output to the effective needs of the central heating
system, means above all reductions in heat loss and thus savings in gas consumption. Furthermore, with the output
variation feature, governed by the relative standards, the boiler maintains near constant thermal efficiency values
and combustion characteristics.
The instructions for adjusting the gas valve are provided in chapter 11.
Output variability on natural gas (G20)
Output variability on L.P.G. (G31)
1 = Model 16
2 = Model 23
3 = Model 30
4 = Model 36
1 = Model 16
2 = Model 23
3 = Model 30
4 = Model 36
Fig. 4b
Fig. 4a
14
17
18
19
20
21
22
23
24
25
26
27
28
29
30
16
31
15
14
13
12
11
15
kW
10
12
14
kcal/h
x 1000
9
11
13
29
37
36
35
34
33
32
31
30
28
27
26
25
20
19
18
17
16
mbar
6
2
3
4
5
7
8
9
10
11
12
13
21
22
23
24
16
15
1
2
3
4
35
25
30
1
mbar
10
29
13
11
9
15
20
27
28
30
kcal|h
x 1000
kW
26
14
12
10
31
32
33
34
25
35
36
37
15
11
12
13
14
15
31
16
30
29
28
27
26
25
24
23
22
21
20
19
18
17
20
19
21
22
18
23
24
17
16
2 3
4
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1, 2, 3 = Positions of the switch on the pump
7.04 characteristics of the pump built into the boiler
(models 16 -23 - 30 pv)
The discharge head and the flow-rate can be adjusted on the pump using the speed selector switch on the pump
itself.
7.05 adjusting the thermal head (∆t) of the heating system (models 16-23-30 pv)
The difference between the supply and return temperature in the central heating system can be adjusted using the
speed selector switch on the pump. In this way, the flow-rate and discharge head of the pump itself are adjusted.
Increasing the rpm of the pump, the ∆t decreases, and vice-versa.
Warning A difference between supply and return temperature of over 20°c may endanger the boiler due to
condensation; a lower ∆t value is thus recommended.
fig. 5
Flow-rate Q (m3/h)
Discharge head h (m)
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.8.7.6.5.4.3.2.1 1.9
Discharge head h (m)
32
Flow-rate Q (m3/h)
.7
.8
.9
1
2
3
4
5
7.06 pressure drop as a function of heating system water fl ow-rate
7.07 Residual discharge head available to the heating system (models 16-23-30 PV)
Note The diagram in fig. 7 refers to the maximum heating pump discharge head/flow-rate with the speed selector
switch in position 3.
fig. 6
fig. 7
.03 .04 .05 .07 .08 .09 .1.06
.3 .4 .5 .7 .8 .9 1.6.2
.2
.3
.4
.5
.6
.7
.8
.9
1
2
3
Pressure drop ∆p (m)
Flow-rate Q (m3/h)
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8. INSTALLATION AND SAFETY DEVICES
• The boiler must only be installed by specialist companies according to the instructions, requirements and laws
in force
• This boiler must only be used for the application it has been specifically designed for.
Important
This boiler is used to heat water to temperatures below boiling, at atmospheric pressure. The boiler must
be connected to a central heating system compatible with its performance and output rating.
8.01 preliminary operations
The boiler must be installed in a suitable room complaint with the standards and regulations in force. Before connecting the boiler, perform the following operations:
• Carefully clean all the pipe work in the heating system to remove any residues or impurities that may compromise
the correct operation of the boiler;
• Check that the boiler is configured for operation with the type of combustible gas available. This is written on
the packaging and on the rating plate;
• Check that the chimney/flue has a suitable draught, is not choked and that there are no discharges inserted
from other appliances, except where the flue has been created to serve a series of appliances, according to the
specific standards and regulations in force. Only after having performed this check can the joiner pipe between
the boiler and chimney/flue be fitted.
• Check any existing flues to make sure they have been carefully cleaned, as any scale flaking off the side walls
during operation may block the passage of the flue gas, creating extremely dangerous situations for the user.
8.02 On-off valves
It is recommended to fit on-off valves between the boiler and the central heating system; these allow the boiler to
be isolated from the heating system, if necessary.
8.03 Boiler room
Warning This appliance can only be installed and operated in permanently ventilated rooms.
8.04 Connection to the fl ue
The flue connection pipe must be no smaller in diameter than the fitting on the draught diverter. Starting from the
draught diverter, it must follow a vertical course of no less than half a metre. The dimensions and installation of
the flues and the connecting pipes must respect the standards in force.
8.05 Heating system connection
Perform the connections to the corresponding fittings according to the positions indicated in figs. 3a and 3b. The
discharge of the safety valve must be connected to a collection container, to avoid water spilling on the ground in
the event of over-pressure in the central heating circuit.
Note if the central heating supply and return pipes follow a course in which, at some point, air pockets may be
created, an air valve should be installed at the corresponding points.
When the boiler is installed below the level of the central heating system, a “flow-stop” valve should be fitted to
stop the natural flow of water in the central heating system.
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8.06 Filling the system
The installer must ensure that the system is provided with a manual or automatic filling system.
The filling pressure when the heating system is cold must be between 0.5 and 1 bar. If, during operation, due to
the evaporation of the gases dissolved in the water, the heating system pressure falls below the minimum value
described above, it should be returned to the initial value. For correct operation, the water pressure in the boiler,
when hot, must be around 1.5 bar.
8.07 Gas connection
The gas connection is made using a pipe, with the fitting of a gas cock.
Please note that any flexible connection pipes must be approved for such use.
8.08 Checks
Fill the system as indicated above. Check the water circuits and combustible gas system for tightness. When checking the gas system for tightness, proceed with care using soapy water.
Note The manufacturer declines all liability for damage to persons or things resulting from the failure to electrically
earth the boiler.
8.09 Safety devices
The rendimax el boiler is fitted with appropriate devices to ensure safety in the event of operating anomalies.
Contact an authorised service centre to check the correct operation of these devices.
8.10 Over-pressure safety device (for models 16, 23 and 30 pv)
This device is designed to prevent the central heating system pressure from exceeding 3 bar.
To check the efficiency of this device, open the system fill valve and check that, on exceeding the pressure value
indicated above, the safety valve intervenes to discharge the excess water
8.11 Temperature limiting device (safety thermostat) with automatic reset
The function of this device is to prevent the temperature of the heating system water from exceeding boiling
temperature.
The maximum activation temperature is 110°c.
The temperature limiting device is automatically deactivated only when the boiler has cooled (the temperature
must fall by at least 10°c) and when the problem has been identified and resolved. The safety thermostat (part 13
in fig. 2) is located on the control panel.
8.12 Flue gas safety sensor device (fl ue gas thermostat)
The boiler is fitted with device for checking the discharge of the products of combustion. If any anomalies arise in
the flue gas discharge system, with the consequent emission of burnt gas into the room, the appliance will shut
down. To measure and control the temperature of the flue gas, the wind-protection hood is fitted with a temperature sensor bulb (pos. 16 fig. 2).
Any release of burnt gas into the room causes the temperature measured by the bulb to increase, and as a consequence the boiler is shut-down within 2 minutes, by cutting off the supply of gas to the burner assembly.
If the flue gas sensor is activated, unscrew the protective cover (3, fig. 2) on the control panel and manually reset
the device. The boiler will recommence operation.
If, in the event of failure, the sensor needs to be replaced, only use original accessories, and check that the electrical
and bulb connections are performed correctly.
N.B. The flue gas sensor must not be bypassed under any circumstances!
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9. ELECTRICAL CONNECTIONS
9.01 electrical connection
The boiler must be connected to a single-phase, 230 volt - 50 hz (phase/neutral) power supply, with 3 a max fuses, and a bipolar switch with minimum contact opening of at least 3 mm fitted between boiler and the source
of power. It is important to always properly earth the boiler. . The control panel is fitted with a terminal block for
connecting the boiler to any room thermostats or electronic temperature control units present (follow the wiring
diagrams in figs. 8 and 9). To access this terminal block and the various components inside the control panel, see
paragraph 9.02.
Note If replacing the power cable, only use “HAR H05 VV-F” 3x0.75 mm2 cables, with a maximum external dia-
meter of 8 mm
Diagram of electrical connections
fig. 8
Note Dashed wiring to be handled by the installer
N.B. The manufacturer declines all liability for damage to persons or things resulting from the failure to electrically
earth the boiler.
24 Ignition electrode
32 Heating system pump (models 16-23-30 pv)
44 Gas valve
49 Safety thermostat
63 Boiler thermostat
72 Room thermostat (not supplied)
82 Detection electrode
83 Electronic flame control unit
92 Flue gas thermostat with manual reset
98 Boiler switch
129 Reset button with pilot light
159 Test knob
160 Auxiliary contact
242 Connector for thermostatic control unit
Page 19
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19
fig. 9
Operating principle wiring diagram
Note Dashed wiring to be handled by the installer
N.B. The manufacturer declines all liability for damage to persons or things resulting from the failure to electrically
earth the boiler.
24 Ignition electrode
32 Heating system pump (models 16-23-30 pv)
44 Gas valve
49 Safety thermostat
63 Boiler thermostat
72 Room thermostat (not supplied)
82 Detection electrode
83 Electronic flame control unit
92 Flue gas thermostat with manual reset
98 Boiler switch
129 Reset button with pilot light
159 Test knob
160 Auxiliary contact
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9.02 opening the control panel
To access the electrical components inside the control panel, follow the sequence in fig. 10.
fig. 10
10. SET-UP
10.01 fi rst ignition
The first ignition and the training of the user for the correct operation of the boiler must be carried out by an
authorised service centre.
10.02 checks to be performed upon fi rst ignition
During the first ignition of the boiler, it is important to check that the on-off valves between the boiler and the
heating system are open; that the heating circuit is filled and vented of air; that there are no gas or water leaks in
the heating system or in the boiler; that the electrical connections are correct and that the earth cable is connected
to an adequate earth system; that there are no inflammable liquids or materials in the immediate vicinity of the
boiler; and that the flue is not blocked.
10.03 ignition
Set the boiler thermostat to the “minimum temperature” position, and power the appliance using the boiler
switch.
To ignite the burner assembly, proceed as follows:
• Open the gas cock (fitted by the installer);
• Vent the air in the gas pipes using the air vent fitted upstream from the gas valve (fig. 11).
• Adjust the knob on the boiler thermostat to the desired value (not less than 50 °C.).
At this stage the electronic control unit starts operating and will pilot, after a set waiting time, the gas valve and
the spark to the ignition electrode, which in turn will light the burner assembly. The ionisation electrode then checks
the presence of the flame in the burner assembly.
The boiler operates automatically, controlled by the boiler thermostat and/or any other control devices (room
thermostat, electronic temperature control unit, etc.).
3
1
5
2
4
Key
1 Boiler cover
2 Protective cover fastening screw
3 Wiring protective cover
4 Fastening plate and screw
5 Control panel
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Note if after having correctly performed the ignition operation, the burners do not light and the reset button light
on the electronic control unit is on, indicating that the control unit is blocked, wait around 10 seconds and then
press the reset button.
The control unit is reset and will repeat the ignition cycle.
If, after the second attempt, the burners do not light, refer to paragraph 13 “troubleshooting”.
In the event of power failures, the burners will shut-down and will be automatically ignited once the power retur-
ns.
10.04 Temporary shut-down
To temporarily shut-down the boiler, simply place the boiler switch in position “0”.
10.05 Extended boiler shut-down
To shut the boiler down, proceed as follows:
• Turn the knob of the boiler switch to position ”0”;
• Close the gas cock upstream from the boiler;
• Disconnect power to the appliance.
N.B. If the boiler is not used for an extended period in winter, to avoid damage from frost, special anti-freeze
should be added to the system, or else the system should be completely emptied.
10.06 checks after ignition
Following the first ignition:
• Check the gas circuit and the heating system for tightness.
• Check the correct operation of the boiler by effecting ignition and shut-down tests using the regulation
thermostat.
• Check on the rear wall of the boiler, at the height of the draught diverter, that there are no flue gas leaks, signs
of blockages of the flue or insufficient draught.
• Check the effectiveness of the flue during boiler operation.
• Check that the connecting pipe between the boiler and flue is perfectly sealed at the joints.
• Verify that the circulation of water between the boiler and the heating system is correct.
• Make sure that, in the absence of a flame in the burner assembly, the appliance shuts-down.
11. SETTINGS
11.01 setting the heating temperature
The central heating water temperature is set by turning the knob on the boiler thermostat, on the control panel.
Turn the knob clockwise to increase the central heating water temperature; anticlockwise to decrease it. The minimum temperature setting must not be below 50°.
11.02 setting the ambient temperature (with room thermostat installed)
The ambient temperature is set by turning the knob on the room thermostat to the desired value. This device,
which is not supplied with the boiler, maintains the ambient temperature at the value set on the knob, reducing
energy consumption and increasing the level of comfort.
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Key
1 Pressure test point upstream
2 Pressure test point downstream
3 Protective cap
4 Adjustment screw
fig. 11
11.04 adjusting the heating system _t by varying the fl ow-rate discharge head of the built-in pump (models 16-23-30 pv)
The thermal head ∆t (difference between the supply and return temperature in the central heating system) must
be less than 20°c, and is adjusted by varying the flow-rate/discharge head of the, using the 3-speed selector switch
on the pump itself. Note that on increasing the speed of the pump, the ∆t decreases, and vice-versa.
11.05 adjusting the central heating system water pressure
The central heating system water pressure, as read on the thermal pressure gauge on the control panel, must be
set according to the instructions provided in paragraph 8.06. In the case of an open vessel system, simply check
the water level periodically.
Decrease
Increase
11.03 adjusting the heating system power
This procedure must be performed with the boiler in operation.
Connect a pressure gauge to the pressure test point 2 (fig. 11) located downstream from the gas valve, and turn
the knob on the boiler thermostat to the maximum value.
After removing the protective cap 3 (fig. 11), adjust the pressure of the gas supplied to the burner assembly, using
the screw 4, to the desired value, referring to the diagrams in figs. 4a and 4b, paragraph 7.02.
Having completed this operation, ignite and shut-down the burner assembly 2, 3 times, using the regulation ther-
mostat, and check that the pressure is equal to the set value; otherwise, make further adjustments until the correct
value is reached.
Electronic Control Unit
Honeywell
S 4565 AD 2056
Gas valve
Honeywell
VK 4105 C 1009
1
2
3
4
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12. GAS CONVERSION
The following adjustment and conversion operations must be carried out exclusively by qualified personnel, such
as those from our sales network or customer service department.
12.01 to change from natural gas (g20) to lpg (g31)
• Replace the burner nozzles (see table of technical specifications).
• Remove the small protective cap 3 from the gas valve (see fig. 12).
• Using a small screwdriver, adjust the ignition ”step” to lpg.
• Replace the small cap 3 on the regulator.
12.02 to change from lpg (g31) to natural gas (g20)
• Follow the operations described in paragraph 12.01 in the reverse order, using the nozzles provided for natural
gas (see table of technical specifications).
1
2
3
4
Key
1 Pressure test point upstream
2 Pressure test point downstream
3 Protective cap
4 “Step” ignition adjuster
fig. 12
Remove the cap and position
the arrow-shaped pointer as
indicated in the figures to
the side, for the various types
of gas.
Adjusting the ignition step
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fig. 13
Key
1 Casing cover
2 Smokebox closing plate
3 Brush
3
2
1
13. CHECKS AND MAINTENANCE
Attention
The boiler’s electrical devices work at 230v ~ 50hz.
Before carrying out any work, make sure the electrical power is removed.
13.01 checking the system boiler (to be performed once a year
The system checks are generally performed at the end of the winter season. Check that the water in central heating
circuit is pressurised. Verify serviceability and operation of the pumps.
Check the correct operation of the boiler by effecting ignition and shut-down tests using the regulation thermostat.
Check on the rear wall of the boiler, at the height of the draught diverter, that there are no flue gas leaks, signs of
blockages of the flue or insufficient draught.
Check the effectiveness of the flue during the operation of the boiler.
Check that the connecting pipe between the boiler and flue is perfectly sealed at the joints.
Check that, in the absence of a flame in the burner assembly, the appliance shuts-down and the light on the reset
button 11, fig. 1, turns on.
13.02 cleaning the boiler and chimney (to be performed once every 3 years)
To properly clean the boiler, proceed as follows:
• Close the gas upstream from the appliance and remove electrical power.
• Remove the boiler door.
• Lift the cover of the casing, applying upwards pressure (fig. 13).
• Remove the smokebox closing plate.
• Remove the burner assembly (see 13.03).
• Clean from top to bottom, using a brush. The same operation can be
performed from bottom to top.
• Clean the flue gas discharge pipes between the cast-iron elements of
the boiler body, using a vacuum cleaner.
• Carefully replace all the previously removed parts and check the gas
circuit and flue pipes for tightness.
• Make sure when cleaning not to damage the bulb of the flue gas
thermostat, fitted at the rear of the smokebox.
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13.03 disassembling and cleaning the burner assembly (to be performed once a year)
To remove the burner assembly, proceed as follows:
• Remove the electrical power and close the gas upstream from the boiler.
• Remove the electronic flame control unit from the gas valve (fig. 14)
• Disconnect the cables from the electrode assembly.
• Unscrew the four screws which fasten the gas supply pipe upstream from the gas valve.
• Unscrew the two nuts which fasten the door of the combustion chamber to the cast-iron parts of the boiler (fig.
15).
• Remove the burner assembly and door of the combustion chamber.
At this stage, the burners can be cleaned and checked. Clean the burners and electrodes using only a non-metallic
brush or compressed air; never use chemicals.
fig. 14
fig. 15
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Key
1 Ionisation electrode
2 Ignition electrode
3mm
2
1
13.04 electrode assemblies
fig. 16
14. TROUBLESHOOTING
Fault
Cause and corrective action
After a number of attempts at ignition, the electronic control unit shuts the boiler down
Check that the supply of gas to the boiler is correct and that the air has been eliminated from the pipes.
Check that the electrodes have been positioned correctly and do not contain deposits (see fig. 16).
Check that the boiler is properly earthed.
Check that the gas valve is powered.
Check the connections to the ignition and ionisation electrodes.
In the ignition phase, there is no spark between the electrodes.
Check that the electrodes have been positioned correctly and do not contain deposits (see fig. 16).
Regulation thermostat set too low.
Check the electrical power supply.
Check the connections to the electronic flame control unit.
Check that the phase-neutral wires are not reversed and that the earth contacts are effective.
Check the pressure of the gas at the inlet and any open gas pressure switches.
Reset the flue gas thermostat.
Check that the room thermostat is closed.
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The burner assembly burns poorly: Flames too high, too low or too yellow
Dirty gas valve filter.
Check the pressure of the gas supply.
Dirty gas nozzles.
Check that the boiler is not dirty.
Check that the ventilation in the room where the appliance is installed is sufficient for correct combustion.
Smell of unburned gas
Check that the boiler is perfectly clean.
Check that there is sufficient draught.
Check that gas consumption is not excessive.
The boiler works but the temperature does not increase
Check the regulation thermostat for correct operation.
Check that the gas consumption is not less than the required consumption.
Check that the boiler is perfectly clean.
Check that the boiler is properly rated for the heating system.
Check that the heating system pump is not blocked.
Temperature of the water supplied to the heating system is too high or too low
Check the operation of the regulation thermostat.
Check that the pump is not blocked.
Check that the circulating pump is adequately rated for the system.
Explosions in the burner assembly. Delays in ignition
Check that the pressure of the gas is correct and that the boiler body is not dirty.
The regulation thermostat starts the boiler with a too-great temperature difference
Check that the bulb is properly inserted in the sheath.
Check the operation of the thermostat.
The boiler produces condensation
Check that the boiler is not working at too-low temperatures (below 50°c).
Check that the gas consumption is correct.
Check the effectiveness of the flue.
The boiler shuts down for no apparent reason
Activation of the flue gas thermostat.
Activation of the safety thermostat (with automatic reset), due to overtemperature.
N.B. Before calling the customer service department, to avoid unnecessary expense, check that boiler shut downs
are not due to interruptions to the gas or electrical power supply.
Page 28
FERROLI S.p.A.
Via Ritonda 78/a
37047 San Bonifacio - Verona - ITALY
www.ferroli.it
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