Ferroli Domitop HF 24-30 E User manual

DOMITOP HF 24 - 30 E FERELLA GOLD HF 24 - 30 MEL
Wall-Mounting Gas
Boiler
Airtight Chamber,
Heating
TECHNICAL
MANUAL


EDITION
09ï2002
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2
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
1. Technical characteristics and data ....................................................... 3
1.1 Introduction ............................................................................................................. 3
1.2 Dimensions and connections .................................................................................. 4
1.3 General view and main components ....................................................................... 8
1.4 Technical data table .............................................................................................. 10
2. Product framework and internal components..................................... 11
2.1 H draulic circuit - heating ...................................................................................... 11
2.2 H draulic circuit - tap water via external boiler...................................................... 15
2.3 Gas circuit ............................................................................................................. 17
2.4 Burner unit............................................................................................................. 21
2.5 Fume circuit........................................................................................................... 23
2.6 Electrical circuit ..................................................................................................... 27
3. Operation ............................................................................................ 30
3.1 Operating principle ................................................................................................ 30
3.2 Operating diagram ................................................................................................ 31
3.3 Control panel ......................................................................................................... 32
3.4 Adjustments ........................................................................................................... 32
3.5 Operating parameter adjustment .......................................................................... 33
4. Troubleshooting ................................................................................. 34
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3
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
1. TECHNICAL CHARACTERISTICS AND DATA
1.1 Introduction
Our appliance is a high-efficiency heat generator for central heating running on natural gas or LPG
(configurable at the time of installation).
The boiler shell consists of a copper laminar exchanger whose particular shape guarantees high
exchange efficiency under all operating conditions and an open-flue burner e uipped with electronic
ignition and ionization flame control.
The boiler is totally sealed off from the installation room: the air needed for combustion is drawn from
outside and the flue gases are expelled by a fan. The boiler outfit moreover includes a variable speed
circulator, expansion tank, safety valve, filler cock, air pressure switch, water pressure switch,
temperature sensor and a safety thermostat.
Thanks to the control and adjustment system, unit operation is for the most part automatic. The power
for heating is automatically governed by the control system according to the indoor characteristics, the
characteristics of the building and of its location.
There are 5 LEDs on the control panel providing information on the units operating status.
General arnings
 Installation and maintenance must be carried out by professionally ualified personnel, according
to current regulations and the manufacturers instructions.
 Incorrect installation or poor maintenance can cause damage or physical injury. The manufacturer
declines any responsibility for damage caused by errors in installation and use or by failure to
follow the manufacturers instructions given in the instructions manual..
 Before carrying out any cleaning or maintenance operation, disconnect the unit from the electrical
power supply using the switch and/or the special cut-off devices.
Certification
The CE marking demonstrates that Ferroli gas units conform to the re uirements contained in the
applicable European directives.
In particular, this unit complies with the following EU directives:
 Gas Appliance Directive 90/396 assimilated with Italian Presidential Decree DPR 15.11.96 no.
661
 Efficiency Directive 92/42 assimilated with Italian Presidential Decree DPR 15.11.96 no. 660
 Low Voltage Directive 73/23 (amended by 93/68)
 Electromagnetic Compatibility Directive 89/336 (amended by 93/68) assimilated with Italian
Presidential Decree DPR 15.11.96 no. 615
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4
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
1.2 Dimensions and connections
Domitop HF 24 E version
760
98
15536 155
460
160100 25 150 25
8480 80
12070 120 150
110
272
249
100
725
114
321 4
Key
1System delivery
2Gas inlet
3System return
4System filler inlet
Top view
Bottom view
CONNECTIONS AXIS
CONNECTIONS AXIS
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5
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Ferella Gold HF 24 MEL version
Top view
Bottom view
123
135
4
1602515025100
271
705
98
15536 155 114
762
70 120 120 150
460
110
271
80
80 80
Top view
1System delivery
2Gas inlet
3System return
4System filler inlet
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6
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Domitop HF 30 E version
Top view
Bottom view
Key
1System delivery
2Gas inlet
3System return
4System filler inlet
77
123
123
4
155
363
460
692
15 430 15
Ø80 Ø80 Ø80
760
120 120
36 215 54
110
202
110
189
175
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7
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Ferella Gold HF 30 MEL version
Top view
Bottom view
12 3
13 5
80 80 80
4
1543015
362
692
36 155 215 54
189 175
760
110 110120120
200
362
460
Key
1System delivery
2Gas inlet
3System return
4System filler inlet
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8
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Key
5 Airtight chamber
7Inlet
10 System delivery
11 System return
14 Safety valve
16 Fan
19 ombustion chamber
20 Burner assembly
21 Main nozzle
22 Burner
26 ombustion chamber insulation
27 opper exchanger
28 Fume manifold
29 Fume outlet manifold
32 Heating circulator
34 Heating temp. sensor
36 Automatic air vent
43 Air pressure switch
44 Gas valve
49 Safety thermostat
50 Heating thermostat
56 Expansion tank
63 Heating temperature adjustment
74 Heating system cock
81 Ignition electrode
82 Detection electrode
84 1st gas valve operator
85 2nd gas valve operator
98 Off-On-Reset switch
114 Water pressure switch
145 Water gauge
187 Fume diaphragm
1.3 General view and main components
HF 24 E MEL version
RESET
OFF
ON
0
5
1
234
6
bar
98 63 145
117 4485841410
34
114
20
21
22 82 81
49
28
5
29 187 43
56
16
27
50
19
26
36
32
°C
DOMITOP - FERELLA GOLD version
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9
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
HF 30 E MEL version
RESET
OFF
ON
0
5
1
234
6
bar
°C
74
43
16
27
29 187
28
5
50
19
26
22 82
56
81
49
20
21
36
32
10 14 784 114485
34
114
98 63 145
DOMITOP - FERELLA GOLD version
Key
5 Airtight chamber
7Inlet
10 System delivery
11 System return
14 Safety valve
16 Fan
19 ombustion chamber
20 Burner assembly
21 Main nozzle
22 Burner
26 ombustion chamber insulation
27 opper exchanger
28 Fume manifold
29 Fume outlet manifold
32 Heating circulator
34 Heating temp. sensor
36 Automatic air vent
43 Air pressure switch
44 Gas valve
49 Safety thermostat
50 Heating thermostat
56 Expansion tank
63 Heating temperature adjustment
74 Heating system cock
81 Ignition electrode
82 Detection electrode
84 1st gas valve operator
85 2nd gas valve operator
98 Off-On-Reset switch
114 Water pressure switch
145 Water gauge
187 Fume diaphragm
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10
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
1.4 Technical data table
Gas supply Pmax Pmin
Heating Power (Net Heat Value - Hi)
Heating Power (Gross Heat Value - Hi)
seful heating power 80°C - 60°C
Powers Pmax Pmin
kcal/h 20,000 8,300
kW 23.3 9.7
kcal/h 24,700 10,700
kW 28.7 12.4
kcal/h 22,200 9,900
kW 25.8 11.2
Dimensions, weights connections
Depth mm 272
Width mm 460
Height mm 760
Boiler water content litres 1.5
Expansion tank pre-filling pressure bar 1
Expansion tank capacity litres 8
Minimum working pressure in heating bar 0.8
Maximum working pressure in heating bar 3
Maximum working temperature in heating °C 90
Electrical protection rating IP 44
Electrical power supply
Power voltage/frequency V/Hz 220/50
Max electrical power absorbed W 125
Heating system connection 3/4
Filling system connection 1/2
Gas system connection inches 1/2
Weight with packing kg 35
Heating
Natural Gas delivery (G20) nm3/h 2.73 1.19
Natural Gas main nozzles (G20) mm 12 x 1.30
Pressure at Natural Gas burner (G20) mbar 11.8 2.5
Natural Gas supply pressure (G20) mbar 20.0
LPG burner (G31) Kg/h 2.00 0.87
LPG main nozzles (G31) mm 12 x 0.77
Pressure at LPG burner (G31) mbar 36.0 7.0
LPG supply pressure (G31) mbar 37.0
Safety valve bar 3
Pmax Pmin
25,800 10,900
30.0 12.7
31,600 13,800
36.8 16.1
28,500 12,500
33.1 14.5
363
460
760
1.7
1
10
0.8
3
90
44
220/50
125
3/4
1/2
1/2
45
3.50 1.53
16 x 1.25
11.8 2.5
20.0
2.57 1.13
16 x 0.75
35.5 7.0
37.0
3
Pmax Pmin
DOMITOP - FE ELLA GOLD 24 KW 30 KW
inches
inches
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11
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
2. PRODUCT FRAMEWORK AND INTERNAL
COMPONENTS
2.1 Hydraulic circuit  heating
Hydraulic diagram for heating
When there is a call for heat, the room thermostat or control system make the burners ignite and the
circulation pump come into operation. The heat contained in the products of combustion is transferred to the
water by the system via the exchanger. For more details on the operating logic, refer to chap.3.
Key
5 Airtight chamber
7Inlet
10 System delivery
11 System return
14 Safety valve
16 Fan
20 Burner assembly
29 Fume outlet manifold
32 Heating circulator
34 Heating temp. sensor
43 Air pressure switch
44 Gas valve
49 Safety thermostat
50 Heating thermostat
56 Expansion tank
74 Heating system cock
81 Ignition electrode
82 Detection electrode
84 1st gas valve operator
114 Water pressure switch
187 Fume diaphragm
222 opper exchanger
43
49 50
56
81
44
32
20
82
222
5
29-187
16
74
14
114
34
-+
10 711
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12
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Circulator (230v/50Hz)
Located on the heating circuit return, it is connected directly to the exchanger
via special forks and connected to the system via a threaded brass section. It
has three delivery/head levels (see diagram). Changing the delivery/head
changes the speed of the water flowing through the boiler exchanger and as
a result the temperature difference ( T) between heating delivery and return.
Clearly, increasing the delivery of the circulator decreases T and vice versa.
If it is not used for a long time, the impeller might jam due to debris in the water.
With the front screw it is possible to access the impeller, which can be freed with
the aid of a screwdriver. The connection to the expansion tank and the air
separator is installed on the pump casing.
Checks
If the pump doesnt work:
 Check that the impeller is free to turn by turning the screw on the front with
a screwdriver.
 Check that both the card and the pump connection are powered.
 If there is no power supply, check the card.
 If there is power, change the pump.
Air separator
This is used to expel the air in the heating circuit automatically and is located
on the pump casing. It is normally accessible either via the fork or by simply
unscrewing it from its seat.
Key
1 - 2 - 3 = Pump selector position
A = Losses of head 24kW version
B = Losses of head 30kW version
m
C.A.
m3/h
0
0,5
1
1,5
2
2,5
3
3,5
4
0,6 0, 1 1, 1, 1, 1, 2 2, 2, 2,6
4,5
5
5,5
6
2,8 3 3,2 3,4 3,6 3,8 40,40,20
B
A
3
2
1
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13
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Expansion tank
It is connected to the pump casing via a pipe with a fork connection. On the 24kW version, it is located above
the pump, while on the 30kW version it is located behind the exchanger, inside the frame. The expansion
tank contains a diaphragm in contact, on one side, with the system water and, on the other side, with the air
under pressure (pre-loaded to 1 bar) inside the tank. By the expansion of the diaphragm and ensuing
compression of the air, the tank compensates for the thermal expansion of the water in the heating system.
.
30kW
10-litre version
24kW
8-litre version
Exchanger
The exchanger is a copper laminar assembly. It comprises a thickly finned portion and four circular pipes
connected together in series. The water exchanges directly with the combustion gases and makes the
system safe via a safety thermostat (100°C) and the limit thermostat (88°C). Due to its shape and design,
the heat gets evenly distributed over all the finning, with conse uent benefits in terms of exchange efficiency
and the life of the exchanger. A special surface treatment protects the exchanger against oxidation and
corrosion.
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14
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Hydraulic unit
This is a single piece of brass to which the
exchanger delivery is connected for ease of
access. It accommodates a number of safety
and adjustment components.
The hydraulic unit includes:
- safety valve
- water pressure switch
- heating sensor
- filler cock
- check valve
Safety valve
It opens if the pressure exceeds 3 bars, making boiler operation safer and
protecting it against overpressure. You are strongly recommended not to use
this valve to drain the system; once open, dirt could remain inside it, preventing
it from closing completely.
Check valve
It ensures the filling system flows only in one direction and remains airtight
along with the cock.
Filler cock
The boiler has a 1/2 connection on the right-hand side of the heating delivery
for filling the system. It is not fitted on the boiler for some markets such as the
British and Belgian ones.
ater pressure switch
It ensures a minimum pressure for the system. It is normally open (NO) and
closes the contact when the pressure exceeds 0.5 bar. It works on low voltage.
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15
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
2.2 Hydraulic circuit - tap water via external boiler
Hydraulic diagram for tap water
The HF is a boiler for heating only. However, if re uired, the HF has a special kit for connecting the boiler
for tap water, too, via an external boiler. The solution shown in the hydraulic diagram has a three-way diverter
valve and a sensor for the external boiler. The kits also contain connection pipes that vary depending on the
model. The tap water temperature can be adjusted by inserting the knob (included in the kit) in the control
panel (D).
43
49 50
56
81
44
32
20
82
222
5
29-187
16
74
14
114
34
7
-+
10
11
VD
B
E
D
C
F
A
Key
5 Airtight chamber
7Inlet
10 System delivery
11 System return
14 Safety valve
16 Fan
20 Burner assembly
29 Fume outlet manifold
32 Heating circulator
34 Heating temp. sensor
43 Air pressure switch
44 Gas valve
49 Safety thermostat
50 Heating thermostat
56 Expansion tank
74 Heating system cock
81 Ignition electrode
82 Detection electrode
84 1st gas valve operator
114 Water pressure switch
187 Fume diaphragm
ABoiler
BExternal boiler
CBoiler expansion tank
DTap water inlet
ETap water outlet
FHeating circuit
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16
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Electrical and plumbing connections
The terminal block for the electrical connections is designed for hooking up the diverter valve and the sensor.
It is necessary to take out the 1.8 KOhm resistor on the probe connection whose job was to simulate a virtual,
always-satisfied boiler.
Boiler connection kit assembly instructions
X4
12345678910111213
X9
12
3
87654321
95
155
A
72
5011434
- Connect the pipes and 3-way valve as shown
in Fig. 1.
- Make the electrical connection to the terminal
block A (Fig. 2) as shown in the diagram
Fig. 3.
 Connect the 3-way valve (Ref. 95).
 Connect the boiler sensor (Ref. 155).
 Take out the resistor between terminals 3
and 4.
- Open the instrument panel, take out the plug
C (Fig. 4) and insert the knob D (Fig. 5)
to adjust the tap water temperature.
24 Kw
30 Kw
Fig. 1
Fig. 1
Fig. 2
Fig. 3
Fig. 4 Fig. 5
1K MK18Y
1K MK19Y
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17
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
43
49 50
56
81
44
32
20
82
222
5
29-187
16
74
14
114
34
-+
11
7
10
2.3 Gas circuit
Gas circuit diagram
Key
5 Airtight chamber
7Inlet
10 System delivery
11 System return
14 Safety valve
16 Fan
20 Burner assembly
29 Fume outlet manifold
32 Heating circulator
34 Heating temp. sensor
43 Air pressure switch
44 Gas valve
49 Safety thermostat
50 Heating thermostat
56 Expansion tank
74 Heating system cock
81 Ignition electrode
82 Detection electrode
84 1st gas valve operator
114 Water pressure switch
187 Fume diaphragm
222 opper exchanger
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18
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
 
25+/-50V DC
COMMON
80+/-110V D
C
B
Gas valve
It supplies gas to the nozzles between a minimum and maximum pressure. For
the valve to work correctly, it is necessary for the pressure upstream from it to
be stable and suited to the type of gas being used, while the valve will supply
a regular pressure to the nozzles. The gas valve contains two operators. The
function of the first one is to open or close, while the task of the second one is
to modulate the capacity according to the systems re uirements. The signal
comes from the card (X6-1/2/3/4) and is in the form of continuous voltage. The
first operator receives fixed voltage that may be between 80 and 110V DC, for
the second operator the voltage will vary between 25 and 54V DC according
to the need of the main card.
Checks
If the valve doesnt work:
 Check there is gas, and that gas comes out of the valve by means of screw
B.
 If there is no gas, you must check there is voltage at the operators. This
makes it possible to understand whether the problem lies with the valve
(there is voltage at the operators) or with the card (there is no voltage at
the contacts X6-1/2/3/4).
Modulation
The control system governs its boiler capacity so as to keep the delivery temperature constant in accordance
with the settings on the control panel. The nozzle gas pressure is modulated by the valve and specifically
via the 2nd operator. The card provides a change in continuous voltage (between 25 and 54 V DC) according
to the difference between the delivery temperature and the set point.
Checks
Modulation can be checked in three ways:
 Visually, by checking the flame.
 Using a pressure gauge to check the gas pressure downstream from the valve.
 Checking the voltage of the second operator on the card (X6, 1/2). This is the most effective method
in some situations. With this test, it is possible to understand whether the problem lies with the valve
or with the card.
Note that with very low pressure upstream from the valve, opening the valve may be slow and the
boiler could shut down due to failed ignition.
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19
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Adjusting burner pressure
Since this unit has flame modulation, there are two fixed pressure settings: the minimum and maximum,
which must be as stated in the technical data chart according to the type of gas.
 Connect a suitable pressure gauge to pressure point B
downstream from the gas valve.
 Disconnect the pressure compensation tube F.
 Take off the protective cap C.
 Set the potentiometer P3 (on the control card) to minimum
(clockwise).
 Run the boiler in heating mode.
 Adjust the minimum pressure with the screw D, clockwise
to decrease it and anticlockwise to increase it.
 Set the potentiometer P3 to maximum (anticlockwise).
 Turn on the TEST function by temporarily bridging X5.
 Adjust the maximum pressure with the screw E, clockwise
to increase it and anticlockwise to decrease it.
 Reconnect the pressure compensation tube F.
 Put the protection screw C back in.
 Disconnect the test jumper.
N.B. The test lasts 5 minutes
C
 
F
E
B
A
D
25+/-50V DC
COMMON
80+/-110V DC
Key
APressure point upstream
BPressure point downstream
CProtection screw
DMinimum pressure
adjustment screw
EMaximum pressure
adjustment screw
FPressure compensation
tube
After checking or
adjusting the
pressure, it is mandatory to
seal the adjustment screw
with paint or a specific seal.
24 W version
30 kW version
W
mbar
18 19 20 21 22 23
5
10
15
20
25
30
35
910 1112 13 14 15 16 17
8
24 25 26 27 28 29 30 31 32 33 34
G31
LPG
G20
Nat. gas
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20
DOMITOP HF 24 - 30 E
FERELLA GOLD HF 24 - 30 MEL
Version - 09.2002
Gas supply conversion
The unit can function with either Natural Gas or LPG and is factory-set for use with one of the two gases,
as clearly shown on the packing and on the units dataplate. Whenever a different gas to that for which the
unit is preset has to be used, a conversion kit will be re uired, proceeding as follows:
1 Replace the nozzles at the main burner, inserting the nozzles specified in the technical data table,
according to the type of gas used.
2 Adjust the burner minimum and maximum
pressures, setting the values given in the
technical data chart for the type of gas
used.
3 Move the jumper JP02 on the card, as
shown in the diagram:
4 Apply the sticker, contained in the
conversion kit, near the dataplate as
proof of the conversion.
Natural gas operation
LPG operation
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