Ferroli Domina F 24-30 E User manual

Supplied By www.heating spares.co Tel. [phone]
DOMINA F 24-30 E FERELLA F 24-30 MEL MILOS AIR COMPACT E
Wall-Mounting Gas Boiler
Airtight Chamber,
for Hot Water
and Heating
TECHNICAL
MANUAL


EDITION
092002

Supplied By www.heating spares.co Tel. [phone]
2
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
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 ................................................................................. 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 Setting operating parameters .............................................................................. 33
4. Troubleshooting .................................................................................. 34

Supplied By www.heating spares.co Tel. [phone]
3
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
1. TECHNICAL CHARACTERISTICS AND DATA
GENERAL
1.1 Introduction
Our appliance is a high-efficiency heat generator for central heating and hot-water production 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, flow meter, safety valve, filler cock, air pressure switch, water pressure switch,
temperature sensors 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. The power for hot water is automatically and continually
governed to ensure a fast delivery and comfort under all operating conditions.
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

Supplied By www.heating spares.co Tel. [phone]
4
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
1.2 Dimensions and connections
Domina F 24 E version
Key
1System delivery
2Tap water outlet
3Gas inlet
4Tap water inlet
5System return
Top view
Bottom view

Supplied By www.heating spares.co Tel. [phone]
5
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
Ferella F 24 MEL version
& Milos Air Compact E version
Key
1System delivery
2Tap water outlet
3Gas inlet
4Tap water inlet
5System return
Top view
Bottom view

Supplied By www.heating spares.co Tel. [phone]
6
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
Domina F 30 E version
Key
1System delivery
2Tap water outlet
3Gas inlet
4Tap water inlet
5System return
Top view
Bottom view

Supplied By www.heating spares.co Tel. [phone]
7
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
Ferella F 30 MEL version
Key
1System delivery
2Tap water outlet
3Gas inlet
4Tap water inlet
5System return
Top view
Bottom view

Supplied By www.heating spares.co Tel. [phone]
8
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
Key
5Airtight chamber
7Gas inlet
8Tap water outlet
9Tap water inlet
10 System delivery
11 System return
14 Sa ety valve
16 Fan
19 Combustion chamber
20 Burner unit
21 Main nozzle
22 Burner
26 Combustion chamber insulation
27 Copper exchanger or heating and tap
water
28 Fume mani old
29 Fume outlet mani old
32 Heating circulator
34 Heating temp. sensor
36 Automatic air vent
42 Tap water temperature sensor
43 Air pressure switch
44 Gas valve
49 Sa ety thermostat
50 Heating thermostat
56 Expansion tank
63 Heating temperature setting
73 Anti reeze thermostat (optional)
R1-R2-R3-R4 Anti reeze heating elements
(optional)
74 Heating system cock
81 Ignition electrode
82 Detection electrode
84 1st gas valve operator
85 2nd gas valve operator
90 Fume detection point
91 Air detection point
98 O -On-Reset switch
114 Water pressure switch
132 Fume de lector
136 Flow meter
145 Water gauge
157 Tap water temperature setting
187 Fume diaphragm
1.3 eneral view and main components
F 24 E/MEL version
Version DOMINA - FERELLA - MILOS

Supplied By www.heating spares.co Tel. [phone]
9
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
F 30 E/MEL version
5Airtight chamber
7Gas inlet
8Tap water outlet
9Tap water inlet
10 System delivery
11 System return
14 Sa ety valve
16 Fan
19 Combustion chamber
20 Burner unit
21 Main nozzle
22 Burner
26 Combustion chamber insulation
27 Copper exchanger or heating and tap
water
28 Fume mani old
29 Fume outlet mani old
32 Heating circulator
34 Heating temp. sensor
36 Automatic air vent
42 Tap water temperature sensor
43 Air pressure switch
44 Gas valve
49 Sa ety thermostat
50 Heating thermostat
56 Expansion tank
63 Heating temperature setting
73 Anti reeze thermostat (optional)
R1-R2-R3-R4 Anti reeze heating elements
(optional)
74 Heating system cock
81 Ignition electrode
82 Detection electrode
84 1st gas valve operator
85 2nd gas valve operator
90 Fume detection point
91 Air detection point
98 O -On-Reset switch
114 Water pressure switch
132 Fume de lector
136 Flow meter
145 Water gauge
157 Tap water temperature setting
187 Fume diaphragm
Version DOMINA - FERELLA

Supplied By www.heating spares.co Tel. [phone]
10
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
1.4 Technical data table

Supplied By www.heating spares.co Tel. [phone]
11
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
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
5Airtight chamber
7Gas inlet
8Tap water outlet
9Tap water inlet
10 System delivery
11 System return
14 Sa ety valve
16 Fan
20 Burner unit
27 Heat exchanger
29 Fume outlet collar
32 Heating circulator
34 Heating temperature sensor
42 Tap water temperature
sensor
43 Air pressure switch
44 Gas valve
49 Sa ety thermostat
50 Heating thermostat
56 Expansion tank
74 Heating system cock
81 Ignition electrode
82 Detection electrode
114 Water pressure switch
136 Flow meter
187 Fume diaphragm
11
10
-+
7
89
43
50
56
81
44
32
49
20
82
27
5
29-187
16
74
14
114
34
136
42

Supplied By www.heating spares.co Tel. [phone]
12
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
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. On boilers
with a twin heat exchanger, it 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 o head 24kW version
B = Losses o head 30kW version

Supplied By www.heating spares.co Tel. [phone]
13
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
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.
Twin Heat Exchanger
The exchanger is a copper laminar assembly. It comprises a thickly finned portion, three circular pipes
containing the heating water and, inside them, another three pipes in the form of a spiral containing the
tap water. The heating water exchanges directly with the burnt gases, while the tap water does not have
this kind of exchange, it receives heat indirectly from the water in the three heating pipes. In this way, the
surface of the coil does not reach very high temperatures so less scale gets formed. In addition, being very
small, it makes the water speed very high over its entire section, making mineral deposits of any kind
negligible. The typical omega shape of the finning ensures an even distribution of the heat 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.
30kW 10-litre
version
24kW 7-litre
version

Supplied By www.heating spares.co Tel. [phone]
14
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
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
- tap water sensor
- tap water 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
This is necessary to ensure no water returns from the heating system to the
tap water circuit.
Filler cock
This is located between the heating delivery and the tap water outlet. 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.

Supplied By www.heating spares.co Tel. [phone]
15
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
2.2 Hydraulic circuit  tap water
Hydraulic diagram for tap water
Key
5Airtight chamber
7Gas inlet
8Tap water outlet
9Tap water inlet
10 System delivery
11 System return
14 Sa ety valve
16 Fan
20 Burner unit
27 Heat exchanger
29 Fume outlet collar
32 Heating circulator
34 Heating temperature sensor
42 Tap water temperature
sensor
43 Air pressure switch
44 Gas valve
49 Sa ety thermostat
50 Heating thermostat
56 Expansion tank
74 Heating system cock
81 Ignition electrode
82 Detection electrode
114 Water pressure switch
136 Flow meter
187 Fume diaphragm
When the card receives a signal from the flow meter indicating a tap-water draw of over 2.5 l/min, the
boiler starts working normally for tap water. If heating was in operation, or the pump was anyhow working,
the boiler will in any case give priority to the tap water, stopping the pump. The tap water does not
exchange directly with the products of combustion, but via the heating water in the exchanger, avoiding
sudden changes in temperature.

Supplied By www.heating spares.co Tel. [phone]
16
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
Flow-rate restrictor
This is a diaphragm downstream from the flow meter. Its task is to limit the tap-
water flow rate; the boiler modulates its capacity to keep the tap-water
temperature set by the user, but since the boiler capacity is limited to its rated
capacity, it is necessary to limit the tap-water flow rate to obtain high T.
Flow meter
Located at the cold water inlet, its task is to provide the card with a signal
at a fre uency (7 Hz per litre) in direct proportion to the tap-water flow rate.
It is composed of a body (stator) and a rotor inside it. There is a filter on its
inlet to prevent foreign bodies damaging it. It should be remembered that
to turn on the boiler for tap-water operation, the tap-water pressure must
be at least 0.25 bars and the draw flow rate must be greater than 2.5 l/min.
Check
To check it works properly, you need to make sure the flow rate is at least
2.5 l/min and then test the signal to the electric card with a fre uency meter.
This makes it possible to understand whether the problem lies with the flow
meter, incorrect contacts, or the card.
In this case, above the flow-
rate limit m, even though
the boiler is working at its
rated capacity, it is not able
to maintain the set tempe-
rature of 50°C.
*

Supplied By www.heating spares.co Tel. [phone]
17
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
Key
5Airtight chamber
7Gas inlet
8Tap water outlet
9Tap water inlet
10 System delivery
11 System return
14 Sa ety valve
16 Fan
20 Burner unit
27 Heat exchanger
29 Fume outlet collar
32 Heating circulator
34 Heating temperature
sensor
42 Tap water temperature
sensor
43 Air pressure switch
44 Gas valve
49 Sa ety thermostat
50 Heating thermostat
56 Expansion tank
74 Heating system cock
81 Ignition electrode
82 Detection electrode
114 Water pressure switch
136 Flow meter
187 Fume diaphragm
2.3 as circuit
Gas circuit diagram

Supplied By www.heating spares.co Tel. [phone]
18
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
Version - 09.2002
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.

Supplied By www.heating spares.co Tel. [phone]
19
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
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. It is advisable to open 1 or 2 taps
to get rid of the excess capacity.
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 pres-
sure, it is mandatory to seal
the adjustment screw with
paint or a specific seal.

Supplied By www.heating spares.co Tel. [phone]
20
DOMINA F 24 - 30 E
FERELLA F 24 - 30 MEL
MILOS AIR COMPACT E
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
pressres, 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