Ferroli ECONCEPT SOLAR ST Troubleshooting guide

cod. -- — 11/2010 (Rev. 00)
ECONCEPT SOLAR ST
INSTRUCTIONS FOR USE, INSTALLATION AND MAINTENANCE

ECONCEPT SOLAR ST
2EN
B
Declaration of conformity
Manufacturer: FERROLI S.p.A.
Address: Via Ritonda 78/a 37047 San Bonifacio VR Italy
declares that this unit complies with the following EU directives:
• Gas Appliance Directive 2009/142
• Efficiency Directive 92/42
• Low Voltage Directive 73/23 (amended by 93/68)
• Electromagnetic Compatibility Directive 89/336 (amended by 93/68)
President and Legal Representative
Cav. del Lavoro
Dante Ferroli
BThis symbol indicates "Caution" and is placed next to all safety warnings. Strictly follow
these instructions in order to avoid danger and damage to persons, animals and things.
AThis symbols calls attention to a note or important notice.
cod. -- - 11/2010 (Rev. 00)
• Carefully read the warnings in this instruction book-
let since they provide important information on safe
installation, use and maintenance.
• This instruction booklet is an integral part of the
product and must be carefully kept by the user for fu-
ture reference.
• If the unit is sold or transferred to another owner or if
it is to be moved, always make sure that the booklet
accompanies the boiler so that it can be consulted
by the new owner and/or installer.
• Installation and maintenance must be carried out by
professionally qualified personnel, according to cur-
rent regulations and the manufacturer's instructions.
• Incorrect installation or poor maintenance can cause
damage or physical injury. The manufacturer de-
clines any responsibility for damage caused by er-
rors in installation and use or by failure to follow the
manufacturer's instructions.
• Before carrying out any cleaning or maintenance oper-
ation, disconnect the unit from the electrical power sup-
ply using the switch and/or the special cut-off devices.
• In case the unit breaks down and/or functions poorly,
deactivate it, do not make any attempt to repair it or
directly intervene. Contact professionally qualified
personnel. Any repair/replacement of products must
only be carried out by qualified professional person-
nel using exclusively genuine parts. Failure to com-
ply with the above could affect the safety of the unit.
• Periodical maintenance carried out by qualified personnel
is essential for guaranteeing good operation of the unit.
• This unit must only be used for the purpose for which
it was designed. Any other use is considered im-
proper and therefore hazardous.
• After removing the packing, check the integrity of the
contents. Packing materials must not be left within the
reach of children as they are potentially hazardous.
• In case of doubt do not use the unit, and contact the
supplier.
• The images shown in this manual are a simplified
representation of the product. In this representation
there may be slight, unimportant differences with the
supplied product.

ECONCEPT SOLAR ST
3
cod. -- - 11/2010 (Rev. 00)
1 Operating instructions ............................................................................................................ 4
1.1 Introduction.............................................................................................................................................4
1.2 Control panel ..........................................................................................................................................5
1.3 Lighting and turning off...........................................................................................................................7
1.4 Adjustments............................................................................................................................................8
2 Installation .............................................................................................................................. 13
2.1 General Instructions .............................................................................................................................13
2.2 Place of installation .............................................................................................................................13
2.3 Plumbing connections ..........................................................................................................................13
2.4 Gas connection ....................................................................................................................................14
2.5 Electrical connections...........................................................................................................................15
2.6 Fume ducts...........................................................................................................................................16
2.7 Condensate drain connection............................................................................................................... 20
3 Service and maintenance...................................................................................................... 21
3.1 Adjustments..........................................................................................................................................21
3.2 Starting .................................................................................................................................................22
3.3 Maintenance.........................................................................................................................................26
3.4 Trouble shooting...................................................................................................................................27
4 Technical data and characteristics ...................................................................................... 29
4.1 Dimensions and connections ............................................................................................................... 29
4.2 General view and main components ....................................................................................................30
4.3 Water circuit .........................................................................................................................................31
4.4 Technical data table ............................................................................................................................. 33
4.5 Diagrams ..............................................................................................................................................34
4.6 Wiring diagram .....................................................................................................................................36
4.7 DBM29 (ECOTRONIC tech) - Solar Controller ....................................................................................38
4.8 FZ4B low temperature zone card ......................................................................................................... 47

ECONCEPT SOLAR ST
4EN
cod. -- - 11/2010 (Rev. 00)
1. Operating instructions
1.1 Introduction
Thank you for choosing ECONCEPT SOLAR ST, a floor-standing boiler with incorporated solar hot water tankFER-
ROLI featuring advanced design, cutting-edge technology, high reliability and quality construction . Please read this
manual carefully since it provides important information on safe installation, use and maintenance
ECONCEPT SOLAR ST is a high-efficiency, low emissions, sealed chamber premix condensing heat generator for
heating and hot water production, running on natural gas or LPG and equipped with a microprocessor control system.
The boiler shell consists of an aluminium lamellar exchanger and a ceramic premix burner equipped with electronic
ignition and ionisation flame control, modulating speed fan and modulating gas valve.
The boiler is arranged for connection to one or more solar collectors, which are used for domestic hot water production
. In fact, the unit has a special, incorporated stratified solar hot water tank and an advanced circuit with variable-speed
solar pump , for maximising the saving obtainable from a solar panel system.
Regarding the production of hot water for heating, ECONCEPT SOLAR ST it is fitted standard with a double internal
circulation, enabling the simultaneous and independent management of two heating zones: a low temperature zone
(floor system) and a high temperature zone (radiators, towel warmers, etc.).

ECONCEPT SOLAR ST
5EN cod. -- - 11/2010 (Rev. 00)
1.2 Control panel
fig. 1 - Control panel
Key
1 = DHW temperature setting decrease button
2 = DHW temperature setting increase button
3 = Heating system temperature setting decrease
button (high temperature zone)
4 = Heating system temperature setting increase
button (high temperature zone)
5 = Display
6 = Summer / Winter mode selection button
7 = Economy / Comfort mode selection button
8 = Reset button
9 = Unit On / Off button
10 = "Sliding Temperature" menu button (high tem-
perature zone)
11 = Set DHW temperature reached
12 = DHW symbol
13 = DHW mode
14 = DHW outlet temperature / setting (flashing dur-
ing "Exchanger protection" function)
15 = Eco (Economy) or Comfort mode
16 = External sensor temperature (with optional ex-
ternal probe)
17 = Appears on connecting the external Probe or the
Remote Timer Control (optionals)
18 = Room temperature (with optional Remote Timer
Control - low temperature zone)
19 = Burner lit and actual power (flashing during
"Flame protection" function)
20 = Antifreeze operation
21 = Heating system pressure
22 = Fault
23 = Heating delivery temperature / setting - high
temperature zone (flashing during “Exchanger
protection” function )
24 = Heating symbol
25 = Heating mode
26 = Set heating delivery temperature reached
27 = Summer mode
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7910
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43
12 14
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15 16
17182021222325
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27
19

ECONCEPT SOLAR ST
6EN
cod. -- - 11/2010 (Rev. 00)
Indication during operation
Heating
A heating demand (generated by the Room Thermostat or Remote Timer Control) is indicated by flashing of the hot air
above the radiator (details 24 and 25 - fig. 1).
The display (detail 23 - fig. 1) shows the actual heating delivery temperature and, during heating standby time, the mes-
sage "d2".
The heating graduation marks (detail 26 - fig. 1) light up as the heating sensor temperature reaches the set value.
fig. 2
Domestic hot water (DHW)
A hot water tank heating demand is indicated by flashing of the hot water under the tap (details 12 and 13 - fig. 1).
The display (detail 14 - fig. 1) shows the actual hot water outlet temperature and, during DHW standby time, the mes-
sage "d1".
The DHW graduation marks (detail 11 - fig. 1) light up as the hot water tank sensor temperature reaches the set value.
fig. 3
Exclude hot water tank (economy)
Hot water tank temperature maintaining/heating can be excluded by the user. If excluded, domestic hot water will only
be delivered by the solar circuit; the latter is managed by the controller DBM29 whose specifications are given in
cap. 4.7 "DBM29 (ECOTRONIC tech) - Solar Controller".
When hot water tank heating is activated (default setting), the COMFORT symbol (detail 15 - fig. 1) is activated on the
display, and when off, the ECO symbol (detail 15 - fig. 1) is activated on the display.
The hot water tank can be deactivated by the user (ECO mode ) by pressing the economy/comfort button (detail 7 -
fig. 1). To activate the COMFORT mode, press theeconomy/comfort button (detail 7 - fig. 1) again.
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comfort

ECONCEPT SOLAR ST
7EN cod. -- - 11/2010 (Rev. 00)
1.3 Lighting and turning off
Boiler not electrically powered
fig. 4 - Boiler not powered
BThe antifreeze system does not work when the power and/or gas to the unit are turned off. To avoid damage
caused by freezing during long idle periods in winter, it is advisable to drain all the water from the boiler, DHW
circuit and system; or drain just the DHW circuit and add a suitable antifreeze to the heating system, complying
with that prescribed in sec. 2.3.
Boiler lighting
Switch on the power to the unit.
fig. 5 - Boiler ignition
• For the following 180 seconds the display will show FH which identifies the heating system air venting cycle.
• During the first 5 seconds the display will also show the card software version.
• Open the gas cock ahead of the boiler.
• When the message FH disappears, the boiler is ready to operate automatically whenever domestic hot water is
drawn or in case of a room thermostat demand.
Turning the boiler off
Press the button (detail 9 - fig. 1) for 1 second.
fig. 6 - Turning the boiler off
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ECONCEPT SOLAR ST
8EN
cod. -- - 11/2010 (Rev. 00)
When the boiler is turned off, the electronic board is still powered.
Domestic hot water and heating operation are disabled. The antifreeze system remains activated.
To re-light the boiler, press the button (detail 9 fig. 1) again for 1 second.
fig. 7
The boiler will be immediately ready to operate whenever domestic hot water is drawn or in case of a room thermostat demand.
1.4 Adjustments
Summer/Winter Switchover
Press the button (part 6 - fig. 1) for 1 second.
fig. 8
The display will activate the Summer symbol (part 27 - fig. 1): the boiler will deliver tap water only. The antifreeze system
stays on.
To turn off Summer mode, press button (part 6 - fig. 1) again for 1 second.
Heating temperature adjustment (high temperature zone)
Use the heating buttons (details 3 and 4 - fig. 1 ) to adjust the temperature from a min. of 20°C to a max. of 90°C.
fig. 9
This temperature becomes the maximum system delivery temperature also for the low temperature zone. Do not set a
lower value than that of “Heating temperature adjustment (low temperature zone)”:
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ECONCEPT SOLAR ST
9EN cod. -- - 11/2010 (Rev. 00)
Heating temperature adjustment (low temperature zone)
With optional remote timer control installed
Use the "Heating temperature adjustment" button (see relevant manual) to adjust the temperature from a min. of 10°C
to a max. of 40°C.
Without optional remote timer control installed
The heating temperature adjustment for the low temperature zone is fixed at 40°C.
This setting must only be modified by qualified Personnel.
Room temperature adjustment
Room temperature adjustment of the high temperature zone can only be managed by a room thermostat; whereas room
temperature adjustment of the low temperature can be managed by a room thermostat or a remote timer control.
Room temperature adjustment (with optional room thermostat)
Using the room thermostat, set the temperature required in the rooms. If the room thermostat is not present, the boiler
will keep the system at the set system delivery set point temperature.
Room temperature adjustment (with optional remote timer control)
Using the remote timer control, set the required temperature in the rooms. The boiler will adjust the system water according
to the required room temperature. For operation with remote timer control, refer to the relevant instruction manual.
Domestic hot water (DHW) temperature adjustment
Use the DHW buttons (details 1 and 2 - fig. 1) to adjust the temperature from a min. of 10°C to a max. of 65°C.
fig. 10
Sliding temperature
When the optional external probe is installed, the control panel display (detail 5 - fig. 1) shows the actual outside tem-
perature read by the probe. The boiler control system works with "Sliding Temperature". In this mode, the heating sys-
tem temperature is controlled according to the outside weather conditions in order to ensure high comfort and energy
saving throughout the year. In particular, as the outside temperature increases, the system delivery temperature is de-
creased according to a specific "compensation curve".
With the Sliding Temperature adjustment, the temperature set with the heating buttons (details 3 and 4 - fig. 1) becomes
the maximum system delivery temperature (high and low temperature zone). It is advisable to set a maximum value to
allow system adjustment throughout its useful operating range.
The boiler must be adjusted at the time of installation by qualified personnel. Adjustments can in any case be made by
the user to improve comfort .
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ECONCEPT SOLAR ST
10 EN
cod. -- - 11/2010 (Rev. 00)
Compensation curve and curve offset - High Temperature Zone
Press the button (detail 10 - fig. 1) once to display the actual compensation curve (fig. 11), which can be modified
with the DHW buttons (details 1 and 2 - fig. 1).
Adjust the required curve from 1 to 10 according to the characteristic (fig. 13).
By setting the curve to 0, sliding temperature adjustment is disabled.
fig. 11 - Compensation curve
Press the heating buttons (details 3 and 4 - fig. 1) to access parallel curve offset (fig. 14), modifiable with the
DHW buttons (details 1 and 2 - fig. 1).
fig. 12 - Parallel curve shift
Press the button (detail 10 - fig. 1) again to exit parallel curve adjustment mode.
Compensation curve and curve offset - Low Temperature Zone with optional Remote Timer Control
connected
Refer to the relevant instruction manual.
Compensation curve and curve offset - Low Temperature Zone without optional Remote Timer Con-
trol connected
Press the ECONOMY/COMFORT button (detail 7 - fig. 1) for 10 seconds; parameter o01 or the actual compensation
curve is displayed, which can be modified with the DHW buttons (details 1 and 2 - fig. 1).
Adjust the required curve from 1 to 10 according to the characteristic (fig. 13). By setting the curve to 0, sliding temper-
ature adjustment is disabled.
Press the heating button (detail 4 - fig. 1) to access parameter o02 or parallel curve offset (fig. 14), modifiable with the
DHW buttons (details 1 and 2 - fig. 1).
Press the ECONOMY/COMFORT button (detail 7 - fig. 1) again for 10 seconds to exit parallel curve adjustment mode .

ECONCEPT SOLAR ST
11EN cod. -- - 11/2010 (Rev. 00)
References for Compensation curve and curve offset
If the room temperature is lower than the required value, it is advisable to set a higher order curve and vice versa. Pro-
ceed by increasing or decreasing in steps of one and check the result in the room.
fig. 13 - Compensation curves
fig. 14 - Example of parallel compensation curve shift
Adjustments from remote timer control (for Low Temperature Zone only)
AIf the Remote Timer Control (optional) is connected to the boiler, the above adjustments are managed accord-
ing to that given in table 1. Also, the control panel display (detail 5 - fig. 1) shows the actual room temperature
read by the Remote Timer Control.
Table. 1
DHW temperature adjustment Adjustment can be made from the Remote Timer Control menu and the boiler
control panel.
Eco/Comfort selection On disabling DHW from the Remote Timer Control menu, the boiler selects
the Economy mode. In this condition, the ECONOMY/COMFORT button
(detail 7 - fig. 1) on the boiler panel is disabled .
On enabling DHW from the Remote Timer Control menu, the boiler selects
the Comfort mode. In this condition , one of the two modes can be selected
with the ECONOMY/COMFORT button (detail 7 - fig. 1) on the boiler panel .
20
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85
20 10 0 -10 -20
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568910 7
OFFSET = 20 OFFSET = 40

ECONCEPT SOLAR ST
12 EN
cod. -- - 11/2010 (Rev. 00)
System water pressure adjustment
The filling pressure with system cold, read on the boiler water gauge, must be approx. 1.0 bar. If the system pressure
falls to values below minimum, the boiler card will activate fault F37 (fig. 15).
fig. 15 - Low system pressure fault
Operate the filling cock (detail 1 - fig. 16) and bring the system pressure to a value above 1.0 bar.
At the bottom of the boiler there is a pressure gauge (detail 2 - fig. 16) to show the pressure even when there is no power
supply.
fig. 16 - Filling cock
AOnce the system pressure is restored, the boiler will activate the 180-second air venting cycle indicated on the
display by FH.
At the end of the operation always close the filling cock (detail 1 - fig. 16)
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ECONCEPT SOLAR ST
13EN cod. -- - 11/2010 (Rev. 00)
2. Installation
2.1 General Instructions
BOILER INSTALLATION MUST ONLY BE PERFORMED BY QUALIFIED PERSONNEL, IN ACCORDANCE WITH ALL THE
INSTRUCTIONS GIVEN IN THIS TECHNICAL MANUAL, THE PROVISIONS OF CURRENT LAW, THE PRESCRIPTIONS
OF NATIONAL STANDARDS AND LOCAL REGULATIONS AND THE RULES OF PROPER WORKMANSHIP
2.2 Place of installation
The combustion circuit is sealed with respect to the place of installation, therefore the unit can be installed in any room.
However, the place of installation must be sufficiently ventilated to prevent the creation of dangerous conditions in case
of even small gas leaks. This safety standard is required by EEC Directive no. 90/396 for all gas units, including those
with sealed chamber.
Therefore the place of installation must be free of dust, flammable materials or objects, or corrosive gases. The room
must be dry and not subject to freezing.
AIf the unit is enclosed in a cabinet or mounted alongside, a space must be provided for removing the casing
and for normal maintenance operations
2.3 Plumbing connections
Important
The heating capacity of the unit must be previously established by calculating the building's heat requirement according
to the current regulations. The system must be provided with all the components for correct and regular operation. It is
advisable to install shutoff valves between the boiler and heating system allowing the boiler to be isolated from the sys-
tem if necessary.
BThe safety valve outlet must be connected to a funnel or collection pipe to prevent water spurting onto the floor
in case of overpressure in the heating circuit. Otherwise, if the discharge valve cuts in and floods the room,
the boiler manufacturer cannot be held liable.
Do not use the water system pipes to earth electrical appliances.
Before installation, carefully wash all the pipes of the system to remove any residuals or impurities that could affect prop-
er operation of the unit.
BAlso, a filter must be installed on the system return piping to prevent impurities or sludge from the system clog-
ging and damaging the heat generators.
The filter must be installed when replacing generators in existing systems. The manufacturer declines any li-
ability for damage caused to the generator by failure to install or inadequate installation of this filter.
Carry out the relevant connections according to the diagram in sec. 4.1and the symbols given on the unit.
The unit has an internal double circulation, which enables the management of two heating zones: a low temperature
zone (floor system) and a high temperature zone (radiators, towel warmers,etc.).
Solar system
The unit has a specific internal circuit for connection to one or more external solar collectors. The internal circuit of
ECONCEPT SOLAR ST comprises: stratified solar hot water tank with solar coil, flow limiter, filling unit, solar safety
valve, variable-speed pump and solar expansion tank. Make the corresponding connections , respecting the instructions
given below.
• It is best to use steel or copper pipes in the solar circuit. Given the high temperatures the heat transfer fluid can
reach, the use of plastic pipes , e.g. in PE or similar materials, is not allowed. Deformation or breakage of the pipes
can cause a general system failure !
• The widths of the pipes must be correctly sized . In particular, too large a size slows the system speed and reduces
its efficiency . To minimise pressure loss in the solar circuit, the speed of flow in the copper pipe must not exceed
1.5 m/s. For ideal transmission of heat, for the collectors a nominal flow of 40 l/h for every m2 of gross collector area
is necessary .
• All the components of the system must be sized in order to ensure an even volumetric flow rate with the required
nominal flow rate .
• The pipes outside the boiler must be provided with adequate thermal protection to prevent excessive heat loss. In
particular, in case if pipes laid outdoors, use insulation resistant to atmospheric agents , UV rays and bird damage.

ECONCEPT SOLAR ST
14 EN
cod. -- - 11/2010 (Rev. 00)
• The solar circuit must be perfectly tight. Check all the joins between pipes and correct execution of any welds. Use
pressure fittings only of the thermal resistance guaranteed by their manufacturer is equal to 200ºC.
• The presence of air in the solar circuit considerably affects its efficiency . It is necessary to install venting devices in
the highest points of the solar circuit (e.g. at the tops of the columns) and make sure the system is completely vented
after commissioning and after every maintenance operation . The delivery and return pipes must be installed with
adequate slopes towards the vents, avoiding the creation of air pockets. Automatic or manual devices (recommend-
ed) can be used as venting devices. The venting devices must be resistant to temperatures up to 150°C. If the sys-
tem is not working and the automatic venting devices are not blocked, steam can come out . Therefore the automatic
venting devices must be blocked while the system is working.
• The solar circuit must be filled with suitable heat transfer fluid, specific for solar systems. Recommended products:
"FERSOL LT" or "FERSOL ULTRA LT" which provide adequate antifreeze protection for temperatures to -12°C and
-25°C respectively. In general, choose the type of fluid according to the outside temperature in relation to the heating
system in the place of installation . Add approx. 7°C to this temperature (e.g. -5°C) as a safety factor : therefore in
the above example, the antifreeze protection of "FERSOL LT" fluid will suffice. FERSOL premixed solar fluid con-
tains non-toxic propylene glycols and corrosion inhibitors thermostable to 300°C (peak temperature limit condition
reachable for very short periods).
• For solar system filling and venting operations, refer to sec. 3.2. For periodical fluid and maintenance checking op-
erations, refer tosec. 3.3.
System water charcteristics
In the presence of water harder than 25° Fr (1°F = 10ppm CaCO3), the use of suitably treated water is advisable in order
to avoid possible scaling in the boiler. The treatment must not in any case reduce the hardness to values below 15°F
(Decree 236/88 for uses of water intended for human consumption). Water treatment is indispensable in the case of
very large systems or with frequent replenishing of water in the system. If partial or total emptying of the system be-
comes necessary in these cases, it is advisable to refill it with treated water.
Antifreeze system, antifreeze fluids, additives and inhibitors
The boiler is equipped with an antifreeze system that turns on the boiler in heating mode when the system delivery water
temperature falls under 6°C. The device will not come on if the electricity and/or gas supply to the unit are cut off. If it
becomes necessary, it is permissible to use antifreeze fluid, additives and inhibitors only if the manufacturer of these
fluids or additives guarantees they are suitable for this use and cause no damage to the heat exchanger or other com-
ponents and/or materials of the boiler unit and system. It is prohibited to use generic antifreeze fluid, additives or inhib-
itors that are not expressly suited for use in heating systems and compatible with the materials of the boiler unit and
system.
2.4 Gas connection
BBefore making the connection, ensure that the unit is arranged for operation with the type of fuel available and
carefully clean all the pipes of the gas system to remove any residues that could affect good functioning of the
boiler.
The gas must be connected to the relative connector (see fig. 33) in conformity with current standards, with rigid metal
pipes or with continuous flexible s/steel wall tubing, placing a gas cock between the system and the boiler. Make sure
that all the gas connections are tight. The capacity of the gas meter must be sufficient for the simultaneous use of all
equipment connected to it. The diameter of the gas pipe leaving the boiler does not determine the diameter of the pipe
between the unit and the meter; it must be chosen according to its length and loss of head, in conformity with current
standards.
BDo not use the gas pipes to earth electrical appliances.

ECONCEPT SOLAR ST
15EN cod. -- - 11/2010 (Rev. 00)
2.5 Electrical connections
Connection to the electrical grid
BThe unit's electrical safety is only guaranteed when correctly connected to an efficient earthing system exe-
cuted according to current safety standards. Have the efficiency and suitability of the earthing system checked
by professionally qualified personnel. The manufacturer is not responsible for any damage caused by failure
to earth the system. Also make sure that the electrical system is adequate for the maximum power absorbed
by the unit, as specified on the boiler dataplate.
The boiler is prewired and provided with a Y-cable and plug for connection to the electricity line. The connections to the
grid must be made with a permanent connection and equipped with a bipolar switch whose contacts have a minimum
opening of at least 3 mm, interposing fuses of max. 3A between the boiler and the line. It is important to respect the
polarities (LINE: brown wire / NEUTRAL: blue wire / EARTH: yellow-green wire) in making connections to the electrical
line. During installation or when changing the power cable, the earth wire must be left 2 cm longer than the others.
BThe user must never change the unit's power cable. If the cable gets damaged, switch off the unit and have it
changed solely by professionally qualified personnel. If changing the electric power cable, use solely “HAR
H05 VV-F” 3x0.75 mm2 cable with a maximum outside diameter of 8 mm.
Solar collector temperature probe
The unit is provided with a temperature probe for positioning on the circuit at the outlet of the last collector .The probe
must be connected to the controller after carrying out the solar circuit filling operations described in sec. 2.3. The con-
troller is located on the left side on the back of the electrical box. The probe must be connected to terminals 5 and 6,
removing the resistances (to be kept for future use).
Room thermostat (optional)
BCAUTION: The room thermostat must have clean contacts. CONNECTING 230 V. TO THE TERMINALS OF
THE ROOM THERMOSTAT WILL IRREPARABLY DAMAGE THE ELECTRONIC CARD.
When connecting a remote timer control or a timer switch, do not take the power supply for these devices from
their cut-out contacts. Their power supply must be taken with a direct connection from the mains or with bat-
teries, depending on the kind of device.
External probe (optional)
Connect the probe to its respective terminals. The maximum permissible length for the boiler - external probe connec-
tion electrical cable is 50 m. A normal 2-wire cable can be used. The external probe should preferably be installed on
the North, North-West wall or that facing the largest area of living room. The probe must never be exposed to the early
morning sun or, insofar as possible, direct sunlight; protect it if necessary. In any case, the probe must not be installed
near windows, doors, ventilation openings, flues or heat sources that could affect the reading.
fig. 17 - External probe positioning not recommended

ECONCEPT SOLAR ST
16 EN
cod. -- - 11/2010 (Rev. 00)
Accessing the electrical terminal block
Follow the instructions given in fig. 18 to access the electrical connections terminal block. The layout of the terminals
for the various connections is given in the wiring diagram in fig. 36.
fig. 18 - Accessing the terminal block
2.6 Fume ducts
The unit is a "C-type" with sealed chamber and forced draught ; the air inlet and fume outlet must be connected to one
of the following extraction/suction systems. The unit is approved to work with all the Cxy flue configurations specified
on the dataplate (some configurations are given by way of example in this section). Some configurations may be ex-
pressly limited or not permitted by law, standards or local regulations. Before proceeding with installation, check and
carefully observe the above-mentioned prescriptions. Also comply with the provisions on the positioning of wall and/or
roof terminals and the minimum distances from windows, walls, ventilation openings, etc.
BThis C-type unit must be installed using the fume suction and exhaust ducts supplied by the manufacturer in
accordance with UNI-CIG 7129/92. Failure to use them automatically invalidates every warranty and relieves
the manufacturer of any liability.
AFor fume exhaust pipes longer than 1 metre, during installation take in account the natural expansion of the
materials when the boiler is working.
To prevent deformations, leave an expansion space of approx. 2 ÷ 4 mm for every metre of pipe.
fig. 19 - Expansion
2 ÷ 4 mm

ECONCEPT SOLAR ST
17EN cod. -- - 11/2010 (Rev. 00)
Connection with coaxial pipes
fig. 20 - Examples of connection with coaxial pipes ( = Air / = Fumes)
For coaxial connection, fit the unit with one of the following starting accessories. For the wall hole dimensions, refer to
sec. 4.1. Any horizontal sections of the fume exhaust must be kept sloping slightly towards the boiler, to prevent any
condensate from flowing back towards the outside and causing dripping.
fig. 21 - Starting accessory for coaxial ducts
Before proceeding with installation, check with table 2 that the maximum permissible length is not exceeded, bearing in
mind that every coaxial bend gives rise to the reduction indicated in the table. For example, a Ø 60/100 duct comprising
a 90° bend + 1 horizontal metre has a total equivalent length of 2 metres.
Table. 2 - Max. length coaxial ducts
ECONCEPT SOLAR ST 18 ECONCEPT SOLAR ST 25
Coaxial 60/100 Coaxial 80/125 Coaxial 60/100 Coaxial 80/125
Max. permissible length 6 m 16 m 5 m 15 m
Reduction factor 90° bend 1 m 0.5 m 1 m 0.5 m
Reduction factor 45° bend 0.5 m 0.25 m 0.5 m 0.25 m
C
13
C
13
C
33
C
33
C
33
C
13
Ø 100
Ø 60
120
142
Ø 80
Ø 127
120
147
Ø 100
Ø 60
041002X0 041006X0 041001X0

ECONCEPT SOLAR ST
18 EN
cod. -- - 11/2010 (Rev. 00)
Connection with separate pipes
fig. 22 - Examples of connection with separate pipes ( = Air / = Fumes)
For connection of the separate ducts, fit the unit with the following starting accessory:
fig. 23 - Starting accessory (code 041039X0) for separate ducts
Before proceeding with installation, make sure the maximum permissible length has not been exceeded, by means of
a simple calculation:
1. Establish the layout of the system of split flues, including accessories and outlet terminals.
2. Consult the table 4 and identify the losses in meq (equivalent metres) of every component, according to the instal-
lation position.
3. Check that the sum total of losses is less than or equal to the maximum permissible length in table 3.
Table. 3 - Max. length separate ducts
Separate ducts
ECONCEPT SOLAR ST 18 ECONCEPT SOLAR ST 25
Max. permissible length 80 meq 75 meq
C 53
C
33 C 53 B 23 C 13
Ø 81Ø 81
65
87
65

ECONCEPT SOLAR ST
19EN cod. -- - 11/2010 (Rev. 00)
Table. 4 - Accessories
Connection to collective flues
fig. 24 - Examples of connection to flues ( = Air / = Fumes)
If you are then going to connect the ECONCEPT SOLAR ST boiler to a collective flue or a single flue with natural
draught, the flue must be expressly designed by professionally qualified technical personnel in conformity with the cur-
rent standards and be suitable for airtight chamber units equipped with a fan.
In particular, flues must have the following characteristics:
• Be sized according to the method of calculation stated in the current standards.
• Be airtight to the products of combustion, resistant to the fumes and heat and waterproof for the condensate.
• Have a circular or quadrangular cross-section, with a vertical progression and with no constrictions.
• Have the ducts conveying the hot fumes adequately distanced or isolated from combustible materials.
• Be connected to just one unit per floor.
• Be connected to just one type of unit (or all and only forced draught units or all and only natural draught units).
• Have no mechanical suction devices in the main ducts.
• Be at a lower pressure, all along their length, under conditions of stationary operation.
• Have at their base a collection chamber for solid materials or condensation equipped with a metal door with an airtight closure.
Losses in meq
Air
inlet
Fume exhaust
Vertical Horizontal
Ø 80 PIPE 1 m M/F 1KWMA83W 1.0 1.6 2.0
BEND 45° M/F 1KWMA65W 1.2 1.8
90° M/F 1KWMA01W 1.5 2.0
PIPE SECTION with test point 1KWMA70W 0.3 0.3
TERMINAL air, wall 1KWMA85A 2.0 -
fumes, wall with antiwind 1KWMA86A - 5.0
FLUE Split air/fumes 80/80 1KWMA84U - 12.0
C 83 C 43
C 43

ECONCEPT SOLAR ST
20 EN
cod. -- - 11/2010 (Rev. 00)
2.7 Condensate drain connection
The boiler is equipped with an internal trap to drain condensate. Fit the inspection union Aand flexible tube B, pressing
it in for approx. 3 cm and securing it with a clamp. Fill the trap with approx. 0.5 l. of water and connect the flexible tube
to the drainage system.
fig. 25