Ferroli OPTIMAX HE PLUS S Troubleshooting guide

INSTRUCTIONS FOR USE INSTALLATION AND MAINTENANCE
cod. 3540R543 - 08/2012 (Rev. 00)

OPTIMAX HE PLUS S

OPTIMAX HE PLUS S
2Cod. 3540R543 - 08/2012 (Rev. 00)
B• 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 AND ISOLATE the boiler from the
electrical power supply.
• 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 per-
sonnel 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.
• Whilst every effort is taken to ensure the accuracy of
the information contained within these instructions,
the details are offered in good faith and the Manufac-
turer accepts no liability for matters arising as a re-
sult of errors and/or omissions.
• Due to the Manufacturers continuous product re-
search and development, the details contained in
this manual may not truly reflect the actual product.
IMPORTANT
•Your "benchmark" Installation, Commissioning and Service Record Log Book is enclosed in the
last pages of this manual. “This record must be completed and left with the end user”.
Ferroli is a member of the Benchmark initiative and fully supports the aims of the programme.
Benchmark has been introduced to improve the standards of installation and commissioning of
central heating systems in the UK and to encourage the regular servicing of all central heating
systems to ensure safety and efficiency. Please see installation and servicing guidelines.
•"Ferroli declare that no substances harmful to health are contained in the appliance or used
during the appliance manufacture”.
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.
2009/142
/
200/1

OPTIMAX HE PLUS S
3
Cod. 3540R543 - 08/2012 (Rev. 00)
1. Instructions ....................................................................................................................... 4
1.1 Introduction ....................................................................................................................................4
1.2 Control panel..................................................................................................................................4
1.3 Turning ON and OFF .....................................................................................................................5
1.4 Adjustments ...................................................................................................................................6
2. Installation.......................................................................................................................... 7
2.1 General Instructions.......................................................................................................................7
2.2 Place of installation .......................................................................................................................8
2.3 Plumbing connections....................................................................................................................8
2.4 Connection to the gas system......................................................................................................10
2.5 Electrical connections ..................................................................................................................10
2.6 Flue system..................................................................................................................................14
2.7 Condensate drain connection ......................................................................................................18
3. Service and maintenance ............................................................................................... 20
3.1 Adjustments .................................................................................................................................20
3.2 Start-up ........................................................................................................................................20
3.3 Commisioning instructions ...........................................................................................................21
3.4 Routine servicing, maintenance & repair .....................................................................................22
3.5 Troubleshooting ...........................................................................................................................24
4. Technical data and characteristics ................................................................................ 26
4.1 Dimensions and connections .......................................................................................................26
4.2 General view and main components............................................................................................27
4.3 Water circuit .................................................................................................................................28
4.4 Technical data table .....................................................................................................................29
4.5 Diagrams......................................................................................................................................30
4.6 Wiring diagram.............................................................................................................................31
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4
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
1. Instructions
1.1 Introduction
Dear Customer,
thank you for choosing the Optimax HE PLUS S, a FERROLI wall-mounted boiler of the latest generation, featuring
advanced design and cutting-edge technology.
Optimax HE PLUS S is a high-efficiency condensing pre-mix appliance for heating with extremely low emissions, running
on natural gas or LPG.
The boiler consists of an aluminium laminar heat exchanger providing effective condensation of the water vapour contained
in the flue gases, permitting extremely high efficiency.
Above the heat exchanger, in the boiler, there is a pre-mix burner, with a large ceramic surface, equipped with electronic
ignition and ionization flame control, which achieves extremely low emissions while ensuring high reliability and long life
operation.
The boiler is totally room sealed from the installation room: the air needed for combustion is drawn from outside. The
boiler also includes a modulating speed fan, modulating gas valve, pump, expansion vessel, safety valve, flow sensor,
temperature sensors, a safety thermostat and a low water pressure switch.
Thanks to the microprocessor control and adjustment system with advanced self-diagnosis, unit operation is for the most
part automatic. The power for heating is automatically governed by the control system.
The display continuously provides information on the unit’s operating status and it is easily possible to obtain additional
information on the sensor temperatures, set-points, etc. or configure them. Any operating problems associated with the
boiler or system is immediately signalled by the display and, if possible, corrected automatically.
1.2 Control panel
fdp
dpngpsu
sftfu
926
2425
23
22
32
547
8
6
fig. 1 - Control panel
KEY
1Domestic Hot Water temperature setpoint decreasing push button (not used) 8Domestic Hot Water symbol
2Domestic Hot Water temperature setpoint increasing push button (not used) 11 Multi-function indication
3Central Heating water temperature setpoint decreasing push button 12 Degrees indication
4Central Heating water temperature setpoint increasing push button 13 Central Heating mode operation
5Display LCD 14 Central Heating symbol
6Reset 15 Burner on and actual load indication
7On-Off push button

5
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Indication during boiler operation
Central Heating mode
The Central Heating heat demand (generated by the OpenTherm Remote Control, the Room Thermostat or the Clock) is indicated by
the flashing of the Hot Air symbol over the radiator (part. 13 and 14 - fig. 1). The display indicates the actual Central Heating water tem-
perature (part. 11 - fig. 1) and during central heating off time the text “d2”.
fdp
dpngpsu
sftfu
fdp
dpngpsu
sftfu
fig. 2
1.3 Turning ON and OFF
Without main power supply
fdp
dpngpsu
sftfu
fig. 3 - Boiler without main power supply
To avoid damage caused by freezing during long
shutdowns in winter, it is advisable to drain all
water from the system.
Ignition
Ensure the power is on to the appliance.
fdp
dpngpsu
sftfu
fig. 4 - Ignition
fdp
dpngpsu
sftfu
fig. 5 - Air purge
For the first 120 seconds, the display shows FH that identifies the Air purge function.
During the first 5 seconds, the display shows the software version of the pcb.
Open the gas cock on the boiler and purge the air from the pipework upstream of the gas valve.
When the FH disappears, the boiler is ready to function automatically whenever the external controls are calling for heat.
•
•
•
•

6
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Turning off
Press the on/off button (part. 7 - fig. 1) for 5 seconds.
fdp
dpngpsu
sftfu
fig. 6 - Turning off
When the boiler is turned off with this key, the p.c.b is still powered, heating operation is disabled and the display is off
however the frost protection will still be active.
To totally isolate close the gas cock ahead of the boiler and disconnect electrical power.
To avoid damage caused by freezing during long shutdowns in winter, it is advisable to drain all water from the
system.
To turn boiler on again, press the on/off button (part. 7 - fig. 1) for 5 seconds
fdp
dpngpsu
sftfu
fig. 7
The boiler is ready to function automatically whenever the external controls are calling for heat.
1.4 Adjustments
Heating temperature setting
To set the system flow temperature, use the CH push buttons (part. 3 and 4 - fig. 1). It can be varied from a minimum of
20°C to a maximum of 90°C.
fdp
dpngpsu
sftfu
fig. 8
Room temperature adjustment (using a room thermostat)
Using the room thermostat, set the temperature desired. Controlled by the room thermostat, the boiler lights and heats
the system water to the system delivery setpoint temperature. The burner shuts down when the desired temperature in
the room is reached.
A room thermostat and programmer are a mandatory requirement (Building regulations Doc ‘L’ 2002).

7
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
2. Installation
2.1 General Instructions
This unit must only be used for its intended purpose. This unit is designed to heat water to a temperature below
boiling point and must be connected to a heating system and/or a water supply system for domestic use, com-
patible with its performance, characteristics and heating capacity. Any other use is deemed improper.
THE BOILER MUST ONLY BE INSTALLED BY QUALIFIED PERSONNEL, IN COMPLIANCE WITH ALL THE INSTRUC-
TIONS GIVEN IN THIS TECHNICAL MANUAL, THE PROVISIONS OF CURRENT LAW, THE REQUIREMENTS OF THE
TECHNICAL STANDARDS (BS) AND ANY LOCAL REGULATIONS AND THE RULES OF PROPER WORKMANSHIP.
Incorrect installation can cause damage or injury for which the manufacturer cannot be deemed responsible.
The unit must be installed in compliance with these instructions and the following standards applicable in Great
Britain.
Gas Safety Regulations (Installations & Use).
Local Building Regulations.
The Building Regulations (Part L).
The Buildings Standards (Scotland - Consolidated) Regulations).British Standards Codes of Practice (BSI):
B.S. 5440 Part 1 Flues
B.S. 5440 Part 2 Air flow and ventilation
B.S. 5449 ......... Forced circulation hot water production systems
B.S. 6798 ......... Installation of gas-fired boilers for hot water
B.S. 6891 ......... Gas systems
B.S. 7671 ......... IEE wiring system standards
B.S. 4814 ......... Specifications for expansion tanks
B.S. 5482 ......... LPG systems
B.S. 7593 ......... Water treatment in central heating systems for DHW production
B.S. 5546 ......... Installation of systems for DHW production
Model Water By-Laws (Great Britain)
B.S. 5955-8 ......... Installation of plastic pipes
For Northern Ireland the relevant laws in force must be observed.
Safe handling of materials
Pay attention when handling the boiler insulation panels because the material they are made of could irritate the skin. No
part of the boiler contains asbestos, mercury or CFC’s.
Advice for transport and handling
For lifting and transport always take suitable safety precautions: keep your back straight, bend knees, do not turn your
body, move feet, avoid bending forward or sideways and keep the load as close as possible to your body.
If possible, use a trolley or other suitable means to carry the boiler.
Grip the boiler firmly and, before lifting it, try and find the point where the load is concentrated in order to establish the
centre of gravity and suitably reposition yourself. Ideally seek assistance in lifting the boiler.

8
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
2.2 Place of installation
The combustion circuit is sealed with respect to the place
of installation and 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 slight gas leaks. This safety regulation is
provided for by EEC Directive no. 2009/142 for all gas units,
including those with a sealed chamber.
In any case, the place of installation must be free of dust,
flammable materials or objects or corrosive gases.
The boiler is arranged for wall mounting and comes stan-
dard with a hanging bracket. A paper template for marking
the drilling points on the wall is provided in the box. The
wall fixing must ensure stable and effective support for the
generator. B B
C
E
D
fig. 9 - Minimum distances around the boiler
If the unit is enclosed in a cabinet or mounted
alongside, a space must be provided for removing
the casing and for normal maintenance operations.
The minimum measurements to be respected are
given in fig. 9.
AMin. 2,5 cm
BMin. 20 cm
CMin. 30 cm
DMin. 35 cm (via an openable panel)
2.3 Plumbing connections
Important
The heating capacity of the boiler must be previously established by calculating the building’s heat requirement according
to the current regulations. To ensure proper operation and long boiler life, the plumbing system must be adequately sized
and complete with all the necessary accessories, including a room thermostat, a thermostatic radiator valve (TRV), etc.
The system flow and return pipes must have a diameter of at least 22 mm for the first 3 m of length from the unit.
If the system delivery and return pipes follow a path where air pockets could form in certain places, it is advisable to
install vent valves at these points. Also, install type “A” drain cocks at the lowest points in the system to allow complete
emptying.
The temperature drop between the delivery manifold and the return to the boiler should not exceed 20 °C.
A flow rate of at least 6 litres/min through the heat exchanger is required. An automatic bypass installed in the boiler
guarantees maintaining of the required flow rate.
Do not use the water system pipes to earth electrical appliances.
Before installation, carefully flush all the heating system pipes to remove any residuals or impurities that could affect
proper operation of the unit (as required by BS 7593 Building regs Doc L).
Carry out the connections to the unit as indicated in fig. 29.
The safety valve discharge must be connected to a 15 mm diameter copper pipe descending from the boiler to
run off system water in case of overpressure in the heating circuit. Otherwise, the boiler manufacturer cannot
be held liable if the discharge valve operates and floods the room. The discharge must be run to the outside of
the building to prevent the risk of damage or injury caused by discharged hot water in case of overpressure in
the system.
Connections to the boiler are to be made in such a way as to ensure that its internal pipes and fittings are free of stress.
If a non-return valve is installed also on the DHW circuit (if provided for), it is necessary to install a safety valve between
the boiler and circuit (with non-return valve at least 3 metres from the boiler) or an expansion tank for domestic use.

9
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Shutoff valve kit
The isolation valve kit shown in fig. 10 is supplied as standard.
Lfz
B!>!Ovu
C!>!Dpnqsfttjpo!pmjwf
E!>!405!tfbm!)hsffo*
F!>!203!tfbm!)hsffo*
G!>!203!hbt!tfbm!)cmvf*
H!>!Gjmufs
I!>!Dbq
Gmpx!jtpmbujpo!wbmwf
Hbt!jtpmbujpo!wbmwf
Sfuvso!jtpmbujpo!wbmwf
33
33
33
B
B
BC
C
C
E
E
G
HI
SFE
ZFMMPX
CMVF
fig. 10
Make up water
Provision must be made for replacing water lost from the sealed system. Reference should be made to BS6798, for
methods of filling and making up sealed systems. There must be no direct connection between the boiler's central heating
system and the mains water supply. The use of mains water to charge and pressurise the system directly, is conditional
upon the Local Water Byelaws. Again any such connection must be disconnected after use. Ensure the filling point is
on the return pipe to the boiler.
Attention - is drawn to the Model Water Byelaws.
Key
1C.H. filling valve.
2Temporary connection.
3Cold water supply valve.
4Double check valve.
fig. 11 - Filling system

10
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Water treatment
If treatment of the water is necessary, Ferroli recommends the exclusive use of specific products such as Fernox or Sen-
tinel to be applied in compliance with the producer’s instructions. For more information, please contact:
Fernox Manufacturing Co. LTD. Sentinel Performance Solutions Ltd
Cookson Electronics, Forsyth Road The Heath Business & Technical Park
Sheerwater, Woking, Surrey, GU21 5RZ Runcorn, Cheshire WA7 4QX
Tel.: [phone] Tel.: [phone]
If the boiler is installed in an existing system, it is necessary to remove any unsuitable additives by thoroughly
cleaning the system. Cleaning of all the systems must be carried out in compliance with the provisions of Stan-
dard B.S. 7593.
In areas characterised by the presence of hard water, treatment may be necessary to prevent the formation of
encrustations in the boiler.
Make sure to use the water treatment product in the correct concentration, in compliance with the producer’s
instructions.
2.4 Connection to the gas system
If necessary the local Gas supplier should be consulted, at the installation planning stage, in order to establish the avai-
lability of an adequate supply of gas.
An existing service pipe must not be used without prior consultation with the local Gas supplier.
A gas meter can only be connected by the Local Gas supplier, or by a Local Gas suppliers Contractor.
Installation pipes should be fitted in accordance with BS6891.
Appliance inlet working pressure must be 20mbar MINIMUM, for NG and 37 mbar minimum for LPG.
Do not use pipes of a smaller size than the combination boiler inlet gas connection (22 mm).
The complete installation must be tested for gas soundness and purged as described in BS689. All pipework
must be adquately supported. An isolating gas valve is provided and should be fitted on the boiler gas inlet.
Please wait 10 minutes when lighting from cold before checking. Gas pressures should be checked after the
boiler has operated for 10 minutes to reach thermal equilibrium. This appliance has no facility to check the burner
pressure, however if the inlet pressure and the gas rate are correct the boiler should be set correctly, the gas
valve is set and sealed at the factory and should not be adjusted without authorisation from Ferroli Personnel.
A combustion test can be carried out to ensure correct air/gas mix (see page 28 combustion analyser
testing).
The isolation kit shown in fig. 10 is supplied as standard.
2.5 Electrical connections
The unit must be installed in conformity with current national and local regulations.
Connection to the electrical grid
The unit’s electrical safety is only guaranteed when correctly connected to an efficient earthing system executed
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 cable and plug for connection to the electricity supply. 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
supply. During installation or when changing the power cable, the earth wire must be left 2 cm longer than the others.
The 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.

11
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Accessing electrical terminal block
The electrical connections terminal block can be accessed after removing the casing. The layout of the terminals for the
various connections is given in the wiring diagram in fig. 35 and 36.
Warning:
the room
thermostat
works at 230V.
Warning:
the room
thermostat
works at 230V.
12 - Electrical terminal block
Room thermostat (optional)
Remove connections 5 - 6 if external control fitted.
If using external controls the switched line can be connected into terminal 5 of the electrical block (see fig 15
and 16).

12
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Central heating Demand
The heat demand can be controlled by the room thermostat (terminal 5-6) or by a switch line 230 V (terminal 5).
Standard Systems
For a general pipe layout and wiring diagram on the “S” and “Y” plan systems please see fig. 13a, 13b, and 14a, 14b.
OPTIMAX “S” Plan
PQUJNBY
GFSSPMJ
CPJMFS
E/I/X/
[pof!Wbmwf
D/I/
[pof!Wbmwf
Bvup!bjs!wfou
fig. 13a - Pipe layout
5432
Kvodujpo!Cpy
OFM
Ufsnjobm!6!.!TXJUDI!MJOF
23456789:21
QSPHSBNNFS
EIX!PO
DI!PO
OFVUSBM
MJWF
DI
{pof
wbmwf
EIX
{pof
wbmwf
Sppn!Uifsnptubu
Dzmjoefs!Uifsnptubu
CSPXO CMVF
HSFZ PSBOHF
M
76
Dfousbm
ifbujoh
qvnq
Qsf.Gjuufe!gmfy
gspn!cpjmfs
O
F341!Wbd
OFM
M
Sfnpwf!Mjol
cfuxffo!ufsnjobmt!6.7
Pomz
Pqujnby
If!QMVT!29!T
fig. 13b -Wiring diagram

13
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
OPTIMAX “Y” Plan
PQUJNBY
GFSSPMJ
CPJMFS
Bvup!bjs!wfou
fig. 14a - Pipe layout
5432
Kvodujpo!Cpy
OM
23456789:21
QSPHSBNNFS
OFVUSBM
MJWF
DI!PO
EIX!PO
EIX!PGG
CMVF
XIJUF
HSFZ
PSBOHF
Sppn!Uifsnptubu
Dzmjoefs!Uifsnptubu
O
F
M
Ipofzxfmm!W5184I!nje!qptjujpo
4!XBZ![POF!WBMWF
3
2
D
Ufsnjobm!6!.!TXJUDI!MJOF
M
76Dfousbm
ifbujoh
qvnq
341!Wbd
OFM
Qsf.Gjuufe!gmfy
gspn!cpjmfs
Pomz
Pqujnby
If!QMVT!29!T
fig. 14b -Wiring diagram

14
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
2.6 Flue system
This unit is a “C type” with sealed chamber and forced draught, with air inlet and flue exhaust to be connected to one
of the following flue systems. Before installation, with the aid of the tables and calculation methods given, check that the
pipes of the fume system do not exceed the maximum permissible lengths. The current standards and local regulations
must be observed.
Only a Ferroli flue system (with respective accessories) must be used with this unit, as required by BS 5440
and CE standards.
Connection with coaxial pipes
Standard connection with coaxial pipes (code 041025G0)
Cfuxffo
21!f!71!nn
Cfuxffo
21!f!71!nn
2
3
4
5
1
CBS
431!nn!)npefm!29!T*
511!nn!)npefm!36!T*
561!nn!)npefm!46!T*
811
411!nn!)npefm!29!T*
441!nn!)npefm!36!T*
441!nn!)npefm!46!T*
236
2:3
311
2:4
91811
Ù211
236
91811
Ù211
Esjmm!uif!xbmm!21ø31!nn
npsf!uibo!uif
qjqf!ejbnfufs
Sfbs!pvumfu
Tjef!wjfx
Tjef!pvumfu
Gspou!wjfx
239!)npefm!29!T*
311!)npefm!36!T*
368!)npefm!46!T*
276!nn!)npefm!29!T*
2:6!nn!)npefm!36!T*
2:6!nn!)npefm!46!T*
fig. 15 - Standard connection
Horizontal flue installation
Define the position for installing the unit.
If using standard flue (041025G0) this must be installed level. For extended horizontal flue lengths over 1m a fall of
3 mm per metre of the flue exhaust should be incorporated back to the boiler.
Make a hole of diameter 10 - 20 mm greater than the nominal diameter of the concentric pipe used.
If necessary, cut the terminal length to size, ensuring that the external pipe protrudes from the wall by between 10
and 60 mm. Remove the cutting burrs.
Connect flue to the boiler, positioning the seals correctly. Seal the flue into the wall with silicone or sand + cement
and cover with wall seals provided.
Flue seals should be lubricated with a silicone type grease to prevent damage (grease not supplied).
1.
2.
3.
4.
5.

15
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Other coaxial connections
D
24
D
24
D
44
D
44
D
44
D
24
fig. 16 - 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
section 4.1 Dimensions and connections.
Ù!211
Ù!71
231
253
Ù!91
Ù!238
231
258
Ù!211
Ù!71
152113Y1 152117Y1 152112Y1
fig. 17 - Starting accessory for coaxial ducts
Before proceeding with installation, check with table 1 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 1 - Max. length coaxial ducts
Coaxial 60/100 Coaxial 80/125
Optimax HE
PLUS 18 S
Optimax HE
PLUS 25 S
Optimax HE
PLUS 35 S
Optimax HE
PLUS 18 S
Optimax HE
PLUS 25 S
Optimax HE
PLUS 35 S
Max permissible (horizontal)
equivalent flue length 8 m 7 m 6 m 30 m 28 m 25 m
Max permissible (vertical)
equivalent flue length 9 m 8 m 7 m 30 m 28 m 25 m
Reduction factor 90° bend 1 m 0.5 m
Reduction factor 45° bend 0.5 m 0.25 m

16
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Connection with separate pipes
D 64
D
44 D24
fig. 18 - Examples of connection with separate pipes ( = Air / = Fumes)
For the connection of separate ducts, fit the unit with the following starting accessory:
Ù!92Ù!92
Ù!76
Ù!98
Ù!76
15214:Y1
fig. 19 - Starting accessory for separate ducts
Before proceeding with installation make sure the maximum permissible length has not been exceeded, by means of a
simple calculation:
Completely establish the layout of the system of split flues, including accessories and outlet terminals.
Consult the table 3 and identify the losses in meq (equivalent metres) of every component, according to the instal-
lation position.
Check that the sum total of losses is less than or equal to the maximum permissible length in table 2.
Table 2 - Max. length separate ducts
Separate ducts
Optimax HE PLUS 18 S Optimax HE PLUS 25 S Optimax HE PLUS 35 S
Max permissible length 95 meq 75 meq 55 meq
Table 3 - Accessories
Losses in meq
Air inlet Fume exhaust
Vertical Horizontal
Ø 80
PIPE 1 m M/F 1.0 1.6 2.0
BEND 45° M/F 1.2 1.8
90° M/F 1.5 2.0
PIPE SECTION with test point 0.3 0.3
TERMINAL air, wall 2.0 -
fumes, wall with antiwind -5.0
FLUE Split air/fumes 80/80 - 12.0
1.
2.
3.

17
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Position of terminals
Q
E-!F
R
R
m
CD
B
H
G
M
K
II
L
O
O
NN
R
fig. 20
Minimum dimensions of fume exhaust terminals
ADirectly under an opening, air inlet, openable window, etc. 300 mm
BAbove an opening, air inlet, openable window, etc. 300 mm
CHorizontally to an opening, air inlet, openable window, etc. 300 mm
DUnder gutters, drain pipes 75 mm
EUnder cornices or under eaves 200 mm
FUnder balconies or garages 200 mm
GFrom a drain pipe or a vertical drain pipe 150 mm
HFrom an internal or external corner 100 mm
IAbove ground level, a roof or balcony 300 mm
JFrom a surface facing the terminal 600 mm
KFrom a terminal facing the terminal 1200 mm
LFrom a garage opening (e.g. door, window) with access to the home 1200 mm
MVertically from a terminal on the same wall 1500 mm
NHorizontally from a terminal on the same wall 300 mm
OFrom the wall on which the terminal is fitted N/A
PFrom a vertical structure on the roof 150 mm
QAbove the intersection with the roof 300 mm
NOTES • N/A = Not applicable
•Also, the terminal must be at least 150 mm (in case of forced intake) from an opening made in the
structure of the building to house a fitted element such as a window frame.
•Positions of condensate drain terminals: if the fume exhaust is provided for at a low level, the potential
effect of the flue gas cloud must be considered. Special flue gas management kits are available by
request.
•The flue gas cloud must not be directed towards:
- A frequented approach
- A window or door
- An adjacent property

18
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Connection to multiple flues or single flues with natural draught
To connect the Optimax HE PLUS S boiler to a multiple flue or a single flue with natural draught, the flue or chimney
must be expressly designed by professionally qualified technical personnel in conformity with the current standards and
regulations.
In particular, flues and chimneys must:
Be sized according to the method of calculation given in the standard.
Be tight with respect to the products of combustion, resistant to the fumes and heat and impermeable to condensate.
Have a circular or square cross-section (some hydraulically equivalent sections are permissible), with a vertical progression
and with no constrictions.
Have the ducts conveying the hot fumes at a suitable distance or separately from combustible materials.
Be connected to just one unit per floor, for not more than 6 units (8 if there is a compensation duct or opening).
Have no mechanical suction devices in the main ducts.
Be at low pressure, all along their length, in conditions of stationary operation.
Have at their base a collection chamber for solid materials or condensate, of at least 0.5 m, equipped with an airtight metal
door.
2.7 Condensate drain connection
Installation
The boiler is equipped with an internal air-trap to drain off the condensate.
Fit the inspection coupling A and the hose B, pushing it on for approximately 3 cm and securing it with a clamp.
Fill the air-trap with approximately 0.5 ltrs of water and connect the hose to the waste system, or soakaway.

,3

fig. 21
•
•
•
•
•
•
•
•

19
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
Condensate drain
If possible, the condensate should be conveyed inside the internal drainage system or pipe. For that purpose, use a
pipe of at least 22 mm diameter and a trap with flexible connection supplied with the unit to facilitate connection of the
condensate drain pipe.
The pipe must be in glue-joined plastic and not in copper, since the condensate has a pH of 4 (slightly acid).
If the condensate drain pipe cannot be ended on the inside, it is advisable to run it outside as shown in the following
figure.
The pipe sections going to the outside are exposed to the risk of freezing in particularly extreme weather conditions. To
prevent this from occurring, it is advisable to reduce the length of the condensate drain pipes and run them on the inside,
as much as possible, before going to the outside. It may also be necessary to insulate the condensate pipe or apply a
trace heating device to prevent freezing of the condensate.
The pipes outside the building must be in glue-joined plastic with increased diameter of up to 32 or 40 mm with a maximum
run of 3m for connection to a condensate collection soakaway or external drain.
If using a condensate collection soakaway, it must be as indicated in the figure below, or use a specific system (such
as Mc Alpine SOAK1GR) available from the majority of suppliers of products and accessories for plumbing or heating
systems.
Fyufsobm
43051nn!Tpmwfou!xfme!qjqfxpsl!3/6!+!Njojnvn!Gbmm!tff!cfmpx
Dfnfou!tfbm
211nn!Ejb!uvcf
Cpuupn!tfbmfe
Mjnf!tupof!dijqqjoht
Hspvoe!mfwfm!)fjuifs0Ps*
Ipmf!efqui!511nn
36nn
3!Spxt!pg
4y23!nn!Ipmft
Joufsobm
.411nn
fig. 22 - Condensate drain

20
OPTIMAX HE PLUS S
Cod. 3540R543 - 08/2012 (Rev. 00)
3. Service and maintenance
All adjustment, conversion, startup and maintenance operations described below must only be carried out by Qualified
Personnel (meeting the professional technical requirements prescribed by current regulations).
FERROLI declines any liability for damage and/or injury caused by unqualified and unauthorised persons tampering with
the unit.
3.1 Adjustments
Gas supply conversion
The unit can operate on natural gas or LPG and is factory-set for use with one of these two gases, as clearly shown onthe
packing and on the dataplate. If a gas different from that for which the unit is arranged has to be used, a conversion kit
will be required, proceeding as follows:
Remove the casing.
Open the airtight chamber.
Release the fixing clip C and remove gas pipe A from the fan - venturi assembly.
Replace injector B, inserted in the gas pipe, with that contained in the conversion kit.
Reassemble gas pipe A with the clip and check the seal of the connection.
Apply the label, contained in the conversion kit, near the dataplate.
Refit the sealed chamber and casing.
Modify the parameter for the type of gas:
• put the boiler in standby mode
• press the DHW buttons details 1 and 2 - fig.1 for 10 seconds: the display shows “P01“ flashing.
• press the DHW buttons fig.1 details 1 and 2 - to set parameter 00 (for use with natural gas) or 01 (for use with LPG).
• press the DHW buttons details 1 and 2 - fig.1 for 10 seconds.
• the boiler will return to standby mode.
Check the working pressure
Using a combustion analyser connected to the boiler fume outlet, check that the CO 2 content in the fumes, withthe
boiler operating at max. and min. power, matches that given in the technical data table for the corresponding type
of gas.
fig. 23 - Changing the gas nozzle
3.2 Start-up
Checks to be made at first lighting, and after all maintenance operations that involved disconnection from the
systems or an operation on safety devices or parts of the boiler:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.