Mandatory warning for CEE countries
Warning: This appliance is designed, approved and inspected to meet the requirements of the English
market. The identification plate located on the inside of the appliance certifies the origin where the
product was manufactured and the country for which it is intended.
If you see any exception to this rule, please contact your nearest Saunier Duval dealer.
Thank you in advance for your assistance.
2
Page 3
INTRODUCTION
The
ISOMAX F
combination boiler with electronic ignition providing central heating and stored hot water.
The boiler is of the I2E+ category for use with Natural Gas (G20) as distributed in the United Kingdom,
or Butane (G30), Propane (G31) or Towns Gas
(G130) with the appropriate conversion kit.
boiler is a wall mounted modulating
The installation must be carried out by a qualified
registered person in accordance with the relevant
requirements of The Building Regulations, The Water Byelaws, The Building Standards (Scotland)
Regulations and any applicable local regulations.
These instructions should be carefully followed for
the safe and economical use of your boiler.
The boiler has a fan assisted balanced flue which
both discharges the products of combustion to and
draws the combustion air from the outside of the
room.
The boiler is suitable for top outlet flue connection
only but, can be fitted with horizontal flue, vertical
flue or twin-pipe flue. Refer to flue catalogue for
further details.
Both the central heating and domestic hot water
temperature are user adjustable from the boiler
control panel.
Domestic hot water demand always has priority
over heating demand.
The boiler is designed for use as part of a sealed
water central heating system with fully pumped
circulation. The pump, expansion vessel and associated safety devices are all fitted within the boiler .
The boiler can be installed against either an external wall or on an adjacent inside wall, that is, the
flue system will pass directly to the rear or to either
side to the terminal fitted on the outside wall face.
COMMISSIONING
Ancillary equipment
A range of flue accessories are available including vertical flues, twin-pipe flues, bends etc.
For further information contact your supplier.
Substances Hazardous to Health
The adhesives and sealants used in this appliance
are cured and give no known hazard in this state.
INSULATION PADS/CERAMIC FIBRE, GLASSYARN,
MINERAL WOOL
These can cause irritation to skin, eyes and the
respiratory tract. If you have a history of skin
complaints you may be susceptible to irritation. High
dust levels are usual only if the material is broken.
Normal handing should not cause discomfort, but
follow normal good hygiene and wash your hands
before eating, drinking or going to the toilet.
If you do suffer irritation to the eyes or severe irritation
to the skin, seek medical attention.
Gas safety (Installation and use) Regulations
In your interests and that of gas safety, it is the law
that ALL gas appliances are installed and serviced
by a qualified registered person in accordance with
the above regulations.
Gas leak or fault
If a gas leak or fault exists or is suspected, turn the
boiler off and consult the local gas supply company or your installation/service company.
Air in the heating system
Persistent air in the heating system may indicate
leaks in the system or corrosion taking place. Call
your Installation/Servicing company.
1-On/Off button
2-Summer/Winter mode selector
3-Hot water temperature adjuster
4-Hot water set point display
5-Graphic display
6-Heating temperature adjuster
7-Heating set point display
8-Display backlight
Overheating safety
In the event of a problem, the overheating safety
devices cause safety shutdown of the boiler. If this
happens, call your Installation/Servicing company.
Boiler controls
The control panel, located at the lower front of the
boiler casing, see diagram 1, allows the boiler to
be started, shut down, controlled and monitored
during use.
Flue
Do not obstruct the outside terminal of the boiler.
15872634
IO
mode
1.5
bar
Diagram 1
Hab 222
3
Page 4
e
CONTROLS AND LIGHTING
Lighting the boiler :
Make sure that:
The boiler is connected to the electrical supply.
The gas service cock is open.
Then follow the instructions below :
Press the On/Off button (1)
1
The pressure must be between 1 and 2 bar. If not, the system must be filled by a competent person.
1.5
bar
To stop the boiler : Press button (1)
IO
1
mode
Hab 264
Setting to the SUMMER position
(Hot water only)
Appuyer sur mode pour sélectionner la position été
Press the mode button to select the summer symbol
mode
1.5
bar
The flame symbol appears
Apparaît lorsque le brûleur
when the boiler is running
est en fonctionnement
Adjusting the hot water temperature
Press + or - to adjust the maximum temperature
Appuyer sur + ou - pour ajuster la température
of the hot water (38°C to 60°C)
maximale de l'eau chaude sanitaire (38
Visual indication of set temperature
Visualisation de la température demandée
°
C à 60°C)
Setting to the WINTER position
2
Press the mode button to select the winter symbol
Appuyer sur mode pour sélectionner la position hiver
The actual temperature
Température actuelle
of the heating system
dans le circuit chauffage
Adjusting the heating temperature
3
Press + or - to adjust the maximum temperature
Appuyer sur + ou - pour ajuster la température
of the heating (38°C to 87°C)
maximale souhaitée du circuit chauffage
(Heating + hot water)
°C
10
Visual indication of set temperature
Visualisation de la température demandé
1.5
bar
Illuminates when
Apparaît lorsque le
the boiler lights
brûleur fonctionne
mode
°C
50
To obtain domestic hot water, open a hot water tap. Hot water always has priority over central heating.
4
mode
60
°C
mode
Hab 261
Page 5
CONTROL OPTIONS
(a) Programmable room stat Part N° 40010,
(b) Isocom combined boiler control &
programmable room stat part N° 85915.
ISOCOM
Diagram 2
DRAINING
Protection against freezing
If the boiler is to be out of use for any long periods
during severe weather conditions, it is recommended that the whole system, including the boiler ,
be drained to avoid the risk of freezing.
If in doubt, consult your servicing company.
The
ISOMAX
that protects the boiler from freezing. If the boiler is
to be left and there is a risk of frost, ensure that the
gas and electrical supplies are left connected. The
frost protection device will light the boiler when the
temperature of the boiler water falls below 6°C.
When the temperature reaches 16°C, the boiler
stops.
Note: This device works irrespective of any room
thermostat setting and will protect the complete
heating system.
has a built in frost protection device
SERVICING/MAINTENANCE
To ensure the continued efficient and safe operation of the boiler, it is recommended that it is
checked and serviced at regular intervals.
The frequency of servicing will depend upon the
installation conditions and usage but, in general,
once a year should be enough.
Draining and filling
Caution: The boiler is installed as part of a sealed
system which must only be drained and filled by a
competent person.
Heating safety valve
CAUTION: A heating safety valve with a discharge
pipe is fitted to this boiler.
The valve MUST NOT BE TOUCHED except by a
qualified registered person. If the valve discharges
at any time, switch the boiler off and isolate it from
the electrical supply. Contact your installation/service company.
Pressure/temperature relief valve
CAUTION: A domestic hot water pressure relief
valve, with a discharge pipe is fitted to this boiler.
The valve MUST NOT BE TOUCHED except by a
qualified registered person. If the valve discharges
at any time, switch the boiler off and isolate it from
the electrical supply. Contact your installation/service company.
Cleaning
The boiler casing can be cleaned with a damp
cloth followed by a dry cloth to polish.
Do not use abrasive or solvent cleaners.
Boiler casing
CAUTION. Do not remove or adjust the casing in
any way, as incorrect fitting may result in faulty
operation. If in doubt, consult your installation/service company.
5
Page 6
TECHNICAL DATA
Heating
Heating outputajustable from 10,4 kW
to 27,6 kW
from 35,484 BTU/H
to 94,170 BTU/H
Efficiency91 %
Maximum heating temperature87 °C
Expansion vessel effective capacity8 l
Expansion vessel charge pressure0,5 bar
Maximum system capacity at 75°C180 l
Safety valve,maximum service pressure 3 bar
Products outlet diameter60 mm
Fresh air inlet diameter100 mm
Hot water
Hot water output, automatically variable from 10,4 kW
to 27,6 kW
from 35,484 BTU/H
to 94,170 BTU/H
Storage capacity43 l
Maximum hot water temperature60 °C
Minimum hot water temperature37°C
Specific flow rate (for 30°C temp rise)13,2 l/min.
Threshold flow rate1 l/min.
Nominal water flow rate11,3 l/min.
Temp./pressure relief valve opening pressure7 bar
Temp./pressure relief valve opening temperature 90°C
Cylinder heat up time7 min.
Time to reheat 70% of storage to 60°C3 min.
Expansion valve setting6 bar
Maximum supply pressure8 bar
Minimum operating pressure0,7 bar
Electrical
Electrical supply230 V
Maximum absorbed power235 W
Level of protectionIP44
Natural Gas (G20)
Ø Burner injector1,20 mm
Inlet pressure20 mbar
Maxi. Burner pressure13,8 mbar
Mini. Burner pressure2,16 mbar
Gas rate maximum3,20 m3/h
Gas rate minimum1,32 m3/h
Butane Gas (G30)
Ø Burner injector0,77 mm
Inlet pressure29 mbar
Maxi. Burner pressure23,8 mbar
Mini. Burner pressure3,6 mbar
Gas rate maximum2,39 kg/h
Gas rate minimum0,99 kg/h
Propane Gas (G31)
Ø Burner injector0,77 mm
Inlet pressure37 mbar
Maxi. Burner pressure30,8 mbar
Mini. Burner pressure3,6 mbar
Gas rate maximum2,35 kg/h
Gas rate minimum0,97 kg/h
Bypass fully shut
1
Open 1/4 turn
2
3
Open 1/2 turn
Open 1 turn
4
Open 2 turns
5
60
50
40
1
2
3
4
5
30
20
10
heating supply and return lines
Available pressure (kPa) between
0
(10 kPa = 1 m WG)
Pom 010 a
120010008006004002000
Flow rate through heating system (I/h)
6
Page 7
DIMENSIONS
The
ISOMAX
- the boiler itself
- the fixing jig
- the flue system
Weight: 71 kg
is delivered in three separate packages:
131
234
890
Diagram 5
HEATING SYSTEM DESIGN
● The
ISOMAX
tallation.
● Heating surfaces may consist of radiators,
convectors or fan assisted convectors.
● The
ISOMAX
floor heating system without the need for a mixing
bottle. The maximum central heating flow
temperature can be set to 53°C on the boiler
printed circuit board during commissioning.
● Pipe sectional areas shall be deter mined in ac-
cordance with normal practices, using the output/
pressure curve (diagram 4). The distribution system
shall be calculated in accordance with the output
requirements of the actual system, not the
maximum output of the boiler. However, provision
shall be made to ensure sufficient flow so that the
temperature difference between the flow and return pipes be less than or equal to 20°C. The minimum flow is 400 l/h.
● The piping system shall be routed so as to avoid
any air pockets and facilitate permanent venting
of the installation. Bleed fittings must be provided
at every high point of the system and on all radiators.
is compatible with any type of ins-
can be piped directly to an under-
600
Hab322
480
● The total volume of water permitted for the heat-
ing system depends, amongst other things, on the
static head in the cold condition. The expansion
vessel on the boiler is pressurised at 0,5 bar (corresponding to a static head of 5 m w.g.) and allows
a maximum system volume of 160 litres for an average temperature of 75°C and a maximum service
pressure of 3 bar . This pressure setting can be modified at commissioning stage if the static head differs. An additional expansion vessel can be fitted
to the system if required, see diagram 8.
● Provision shall be made for a drain valve at the
lowest point of the system.
● Where thermostatic radiator valves are fitted, not
all radiators must be fitted with this type of valve,
and in particular, where the room thermostat is installed.
● In the case of an existing installation, it is ESSEN-
TIAL that the system is thoroughly flushed prior to
installing the new boiler.
Filling the system
A filling device must be fitted to the system to initially
fill the system and replace water lost during
servicing,see diagram 8.
7
Page 8
DOMESTIC HOT WATER SYSTEM DESIGN
● Copper tubing or plastic Hep
the domestic hot water system. Unnecessary
0 may be used for
2
pressure losses should be avoided.
● A flow restrictor limiting the flow through the boiler
to a maximum of 16 l/min is fitted to the boiler.
● The boiler will operate with a minimum supply
pressure of 0,7 bar, but under reduced flow rate.
Best operating comfort will be obtained from a supply pressure of 1 bar.
A-Heating return
B-Cold water inlet
C-Heating flow
D-Domestic hot water outlet
E-Gas
D1 - Discharge from HTG safety valves
D2 - Discharge from DHW safety valves
D3 - Discharge from temp/press (to tundish)
19
16
25
Diagram 6
'Hard Water Areas'
In areas where the water is 'hard', more than
200mg/litre, it is recommended that a proprietary
scale reducer is fitted in the cold water supply to
the boiler.
23
12
27
11
21
22
15
18
17
14
7
20
9
8
3
4
2
1
6
5
26
24
13
1028
ABCDE
D1
D1
D2
D1
D3
D1
Shy 163cUK
Valve
outlet size
Minimum
size of
discharge
to tundish
G 1/215 mm22mmup to 9 m0.8 m
G 3/422 mm28 mmup to 9 m1.0 m
G 128 mm35 mmup to 9 m1.4 m
Minimum
size of
discharge
pipe D2
from
tundish
28 mmup to 18 m1.0 m
35 mmup to 27 m1.4 m
35 mmup to 18 m1.4 m
42 mmup to 27 m1.7 m
42 mmup to 18 m1.7 m
54 mmup to 27 m2.3 m
Maximum
resistance
allowed
expressed as a
length of
straight pipe
i.e. no elbows
or bends
Resistance
created by
each elbow or
8
bend
Discharge from HTG+
domestic prv on jig
D1D3
Diagram 6a
Discharge from DHW
safety valves
D2
Tundish
Gully
Page 9
FIXING JIG
The fixing jig is made up, from left to right, as follows:
A- Heating return fitting with isolating valve(v) and
drain knob (u).
B- Cold water inlet fitting with isolating valve
(m)and factory fitted flow regulator and filter (not
shown).
Diagram 7
A
BCDE
u
➜
m
➜
10
v
C- Heating flow fitting with isolating valve (q),
drain knob (r) and safety valve (10).D- Domestic hot water outlet fitting with safety
valve (28).E- Gas fitting.
r
q
28
Pla 213
PIPING SYSTEM INSTALLATION
● Heating system connections - Pipe diam. 22mm
● Hot water system connections - Pipe diam. 15mm
● Gas connection - Pipe diam. 22mm
● Domestic safety valve connection - Pipe
diam.15mm
● Heating safety valve connection - Pipe diam.
15mm
Water connection
Connect the copper connections supplied, to the
fixing jig fittings, see diagram 7. Connect the sys-
Additional
expansion
vessel
(if required)
Return
Heating
circuit
Flow
control valve
Boiler
Bypass
valve
Filling device
Drain point
Domestic
water
Hot
Cold supply
Pressure
reducing
valve
(supplied)
tem pipework to the boiler observing the correct
flow and return format as shown in diagram 8.
There are two sets of two safety valves fitted to this
appliance. Two are located on the jig diagram 7,
(10) heating safety valve 3 bar, and (28) DHW
safety valve 10 bar . The other two are located inside
the boiler (diagram 6,) (27) pressure/temperature
relief safety valve 7 bar/90°C, and (24) DHW safety
valve 6 bar.
Thermostatic
MIX
HC
Temperature
adjustment
mixing valve
Thermostaticaly
controlled
hot water
Boiler
"set temperature"
hot water
Diagram 8
Sch 173a
9
Page 10
PIPING SYSTEM INSTALLATION
Step. 1
The internal safety valves have been tee'd together
and the discharge pipe run so that it exits at the
right hand bottom of the boiler (diagram 6) (D2).
The tundish (supplied) must be used with this outlet
within the normal guidelines and code of practice
(diagram 6a).
Step 2
Tee the domestic safety valve (diagram 7) (28)
outlet to the heating safety valve (10) outlet
together. You can either extend this pipe
horizontally to the outside wall. WARNING, It must
not discharge above an entrance or window or
any type of public access area, the discharge must
be extend using no less than 15 mm o.d. pipe to
discharge in a visible position outside the building,
facing downard preferably over a drain. The pipe
must have a continuous fall and be routed to a
position so that any discharge of water, possibly
steam, cannot create any danger to persons,
damage to property or external electrical
components and wiring.
alternatively : The discharge pipe can be tee'd into
the other discharge pipe after the tundish (diagram
6) provided that it has a continuous fall and that
provisions are made for the size of discharge pipe
immediately after the tundish (see diagram 6a)
Safety valve discharge
Domestic hot water supply options
Under normal circumstances, the domestic hot
water storage temperature inside the boiler can
be stored between 37 and 60° C. It is
recommended that the boiler storage temperature
is set by the user to the maximum of 60°C - this will
ensure a more plentiful supply of hot water.
.
To pipe the hot water supply using the mixing valve,
refer to diagram 8. This shows one outlet supplying
hot water at the boiler hot water "set temperature"
and one hot water outlet at a temperature pre-set
at the mixing valve. The mixing valve can be set
between 35 and 60°C. It is recommended that the
valve is adjusted (and locked) by the installer to
the desired temperature.
The connections to the mixing valve are :
H- Hot water supply from boiler
C- Reduced cold water supply
MIX- Thermostatically controlled outlet
Warning : It is strongly recommended that the cold
water supply to the mixing valve is taken from the
reduced side of the pressure reducing valve
(supplied)
Note 1 : The mixing valve is fitted with two in-line
strainer, one on the hot inlet and one on the cold
inlet. For servicing details of these, refer to the
separate instructions supplied with the mixing valve.
Note 2 : The mixing valve incorporates a "rapid
failsafe" device which will automatically close the
valve to safety in the event of supply failure on
either hot or cold water.
The discharge must be extended using not less than
22 m o.d. pipe, to discharge in a visible position
outside the building, facing downward preferably
over a drain.
The pipe must have a continuous fall and be routed
to a position so that any discharge of water, possibly boiling or steam, cannot create any danger to
persons, damage to property or external electrical components and wiring. Tighten all pipe connection joints.
It may be desirable to provide hot water to
separate outlets at different temperatures (for
example, to provide a limited temperature to
prevent the risk of scalding). To be able to do this,
a thermostatic mixing valve is supplied with the
Isomax boiler (factory set to 43°C) and can be fitted
during the installation procedure.
There are 2 options for the domestic hot water
supply :
1 - Piping the hot water supply without the use of
the mixing valve to provide hot water to all taps at
the same temperature.
2 - Piping the hot water supply using the mixing
valve (supplied) to provide hot water at boiler hot
water “set temperature” to one tap and
thermostatically controlled hot water to another
tap(s).
Gas connection
● The supply from the governed gas meter must be
of adequate size to provide a constant inlet working pressure of 20 mbar (8 in w.g.).
To avoid low gas pressure problems, it is recommended that the gas supply is connected using 22
mm pipe.
● On completion, the gas installation must be
tested using the pressure drop method and purged
in accordance with the current issue of BS6891.
Gas Safety (Installation and use) Regulations
In your interests and that of gas safety, it is the law
that ALL gas appliances are installed and serviced
by a qualified registered person in accordance with
the above regulations.
10
Page 11
BOILER LOCATION
Clearances
The position of the boiler must be such that there is
adequate space for servicing.
The recommended clearances are:
20 mm either side of the boiler.
600 mm at the front of the boiler.
300 mm below the boiler.
● Place template on wall in required position, mak-
ing allowances for the necessary clearances etc.
Note: It is permissible to install the boiler with smaller
clearances than those quoted above PROVIDING
that adequate consideration is given for Servicing/
Repairs at a later date. If any doubt exists, contact
the Saunier Duval T echnical Helpline 01773 828400.
● Mark the position of the holes for the hanging
bracket and jig.
● Drill, plug and fix the hanging bracket to the wall
using suitable screws.
● Check that the hanging bracket is level.
● Drill plug and fix the fixing jig to the wall.
● For horizontal flue system, mark the position for
the flue hole as follows:
Flue to rear of boiler
● Mark correct position of hole from template.
Diagram 9
Ø 105 pour sortie ventouse (type F)
Ø 105 or 125 core drill
169
65
900
2,10 m au sol (pour les modèles type C)
==
20 mm
mini
120
600
234
20
per metre of flue DOWNWARD towards the terminal. There must NEVER be a downward incline towards the boiler.
Ins 090a
Flue to side of boiler
● Mark the horizontal centre line for the hole on the
rear wall. Extend the horizontal centre line to the
side wall and mark the vertical centre line of flue
hole as shown in diagram 9.
Terminal position
The minimum acceptable spacings from the terminal to obstructions and ventilation openings are
shown in diagram 10.
The boiler must be installed so that the terminal is
exposed to the external air.
Cutting the flue hole
● Making allowance for the slope of the flue, cut
hole in external wall, preferably using a core drill.
Should any doubt exist as to the permissible position of the terminal, contact the Saunier Duval
Technical Helpline 01773 828400.
For installations with internal and external access
use a 10 5 mm diameter core drill.
For installations with internal access only use a 125
mm diameter core drill.
Terminal guard
If a terminal guard is required, a suitable guard can
be obtained from your supplier , Saunier Duval part
number 85373.
Important
When cutting the flue hole and when extending
the flue centre line to a side wall, remember that
the flue system must have a fall of about 35 mm
Cupboard or compartment ventilation
The boiler can be fitted in a cupboard or compartment without the need for permanent ventilation.
Minimum dimensions (in mm) for the positioning of flue terminals
A-Under a window .................................................... 300
B-Under an air vent .................................................. 300
C-Under a gutter ......................................................... 75
D-Under a balcony ................................................... 300
E-From an adjacent window .................................. 300
F-From an adjacent air vent................................... 300
G-From vertical or horizontal air pipes.................... 300
H-From an external corner of the building............ 300
I-From an internal corner of the building ............. 300
L-From the ground or from another floor .............. 300
M-Between two terminals vertically ...................... 1500
N-Between two terminals horizontally .................... 600
The installation of this boiler must be carried out by
a qualified registered person in accordance with
the relevant requirements of the current issue of:
The Gas Safety (Installation and Use) Regulations
The Building Regulations
The local water company Byelaws
The Building Standards Regulations (Scotland)
The Health and Safety at Work Act
Sheet metal parts
WARNING. When installing or servicing this boiler,
care should be taken when handling the edges of
sheet metal parts to avoid the possibility of personal
injury.
FLUE INSTALLATION
Top outlet flue - kit 85090
The boiler is only suitable for top outlet flue
connection.
Rear flue systems
The calculate the lenght when flueing to the rear
measure e (diagram 11) plus 25 mm outer flue pipe
and e plus 125 mm to inner pipe measurement.
Installing the boiler
Prior to starting work, the system must be thoroughly
flushed using a propriety cleanser such as SentinelX300 to eliminate any foreign matter and contamination e.g. metal filings, solder particles, oil, grease
etc.
Note. Solvent products could cause damage to the
system.
● Engage boiler upper part onto the hanging
bracket.
● Fit the washers between the boiler pipes and the
inlet and outlet fittings on the fixing jig and connect the various couplings between the boiler and
jig.
Calculation of cutting lengths when flueing to the
right or left
● Measure wall thickness e (mm), see diagram 11.
For right hand applications
● Measure distance from inside face of wall to side
of the boiler a (diagram 11) add 350 mm to outer
pipe measurement and 445 mm to inner pipe
mesurement.
For left hand applications
● Measure distance from inside face of wall to side
of the boiler a (diagram 11) subtract 25 mm for
outer pipe length and add 75 mm to inner pipe
length measurement.
● Refer to table 2 for cutting lengths of both inner
and outer flue pipes for each of the various flue
options available.
Important: All flue cutting lengths must be measured from the terminal end of the flue pipes, see
diagram 12.
When the dimension X measured on site is greater
than that given in table 2. Extensions will be required
as necessary.
Important: All cutting lengths should be measured
from the push fit joint end of the extension pipe.
Do not leave any burrs or sharp edges on the cut
ends of the pipes.
Note : maximum horizontal flue lenght without
bends is 3 m.
ee
a
X
Diagram 11
Diagram 12
Table 2
Flue cutting lengths (mm)
Rear flue
Outer pipe : e + 25,inner pipe : e + 120
Comment : maximum distance 'x' without extension 770 mm
Right side flue
Outer pipe : e + a + 350, inner pipe : e + a + 450
Comment : maximum distance 'x' without extension 515 mm
Left side flue
Outer pipe : e - 25,inner pipe : e + 125
Comment :
maximum distance 'x' without extension 1087 mm
Outer pipe
Cutting length
Inner pipe
Cutting length
a
X
Hab 210a
Ven 089
12
Page 13
FLUE INSTALLATION
Installation of flue assembly
● Fit rubber sealing collar (F), see diagram 13, into
groove at the outer end of pipe (A).
● Fit outer pipe (A) into wall with groove to the out-
side.
● Pull pipe inwards to bring rubber sealing collar
hard up against external wall, see diagram 14.
● Fit internal plastic flange (G) onto outer pipe. Push
along the pipe until engaged against internal wall.
● From inside, insert inner pipe (B) into outer pipe.
● Fit both ‘O’ rings (J) into the flue elbow (C), one
at the inlet, one at the outlet. By necessity, they
are a loose fit, apply a small amount of silicone
grease to each ‘O’ ring when fitting.
● Wrap sleeve (D) over outer pipe (A) and elbow
(C) ensuring it is the correct way round.
● Take hold of the inner flue and push gently onto
the elbow outlet taking care not to tear the ‘O’
ring.
● Open fixing collard (D) and locate between
elbow and outer pipe (A). Close fixing jig.
● Engage the two fixing clips (E) onto the colar
onto (D) and press down to lock into position.
Secure clips with screws provided.
Important: If the flue has been cut, ensure that there
are no burrs that could damage the ‘O’ ring.
● For flue systems less than 1,5 m long, leave the
restrictor (a) fitted in the fan outlet, see diagram
15.
● Remove the backing from the self adhesive gas-
ket (H) and carefully fit gasket to base of flue elbow.
● Fit elbow onto boiler and secure with the four
screws (I).
Diagram 13
A
B
E
C
D
H
The flue kit 86285 is 1000 mm long and comprises:
- Outer pipe .............................................................. A
The maximum permissible length (L) for the concentric flue system is 3 m. For flue systems up to 1,5 m
length, the restrictor (a) supplied fitted to the boiler , inside the fan outlet, must be left in place. For longer
flue systems, the restrictor must be removed.
For each 90° flue elbow used, (or two 45° elbows) the maximum permissible length (L) must be reduced
by 1 metre.
L
Gasket
a
Diagram 15
65
234
13
Hab 249a
Page 14
ELECTRICAL CONNECTION
Warning. This boiler must be earthed
All system components must be of an approved
type.
Connection of the whole electrical system and any
heating system controls to the electrical supply must
be through a common isolator.
Isolation should preferably be by a double pole
switched fused spur box having a minimum contact separation of 3 mm on each pole. The fused
spur box should be readily accessible and preferably adjacent to the boiler. It should be identified
as to its use.
A fused three pin plug and shuttered socket outlet
may be used instead of a fused spur box provided
that:
a) They are not used in a room containing a fixed
bath or shower.
b) Both the plug and socket comply with the current issue of BS1363.
The mains electrical supply must be maintained at
all times in order to provide domestic hot water.
Do not interrupt the mains supply with a time switch
or programmer.
WARNING: ON NO ACCOUNT MUST ANY EXTERNAL
VOLT AGE BE APPLIED TO ANY OF THE TERMINALS ON
THE HEATING CONTROLS CONNECTION PLUG.
The boiler will work for heating without a room thermostat being connected provided that the wire
link fitted between the two terminals of the connector (E) is left in place, see diagram 17.
Alternatively, a 230V room thermostat can be used
but do not make any connection to the compensating resistor, see diagram 17.ON NO ACCOUNT must any electrical voltage be
applied to any of the terminals of the external controls plug.
Note: For further information, see the building
regulations 1991 - Conservation of Fuel and Power
- 1995 edition - appendix G, Table 4b.
The boiler is supplied with a mains lead attached. Connect this to the electrical supply.
Warning: This appliance must be wired in accord-
ance with these instructions. Any fault arising from
incorrect wiring cannot be put right under the terms
of the Saunier Duval guarantee.
External controls
The ISOMAX boiler is designed to operate at maxi-
mum efficiency at all times, but will be most efficient and economical when connected to a room
thermostat.
A suitable room thermostat is available as an accessory, Saunier Duval part number 40011. Please
contact your supplier.
Also available :
For extra control or if the boiler is to be sited in a
garage or utility room an optional remote control
unit with programmable roomstat can be obtained
part number 85915 (Isocom), diagram 2. This is a
dual function unit (a) boiler control (same as boiler
facia) (b) programmable room stat. Full fitting
instructions supplied with the unit.
Isocom only
F
Diagram 16
Leave link in place for no external controls.
F
Diagram 17
IMPORTANT
With voltage free room
thermostat
Without room
thermostat
E
¡C
Ins 060
Sch 171
14
Sch 172
EE
Page 15
COMMISSIONING
d
The commissioning and first firing of the boiler must
only be done by a qualifed registered person.
Gas installation
It is recommended that any air is purged from the
supply at the gas inlet test point on the gas valve,
see diagram 18.
Filling the system
Press the mains 'On/Off' button
1
Le témoin lumineux clignote
The warning light will illuminate
L'afficheur indique 0 bar de pression et clignote
The display will indicate 0 bar pressure in the system
0.0
bar
Diagram 18
Reg 018
IO
1
mode
v
➜
m
➜
Open the boiler isolating valves (v
and q), the slot of the screw corre-
2
sponds to flow direction.
Fully open valve m by turning anticlockwise.
4
Open filling device fitted previously, fill the system
until the pressure indicated on the display is between
1 and 2 bar. Close filling device.
q
3
Undo cap
on automatic air
vent on
top of
pump and
leave un-
Pla 213
done.
The pressure must be between 1 and 2 bar
Hab 260
Reg 008
mo
1.5
bar
Hab 265
15
Page 16
COMMISSIONING
Bleed each radiator to re-
576
move the air, re-tighten
bleed screws.
➜
Ins 061
Make sure the display indicates a system pressure of between 1 and 2 bar. Re-fill system as
8
necessary.
The pressure must be between 1 and 2 bar
Leave the cap on the
pump auto air vent open.
➜
Reg 008
Open various hot
water taps to bleed
system.
Ins 062
IO
1.5
bar
mode
Hab 265
16
Page 17
COMMISSIONING
e
Lighting the boiler :
Make sure that:
The boiler is connected to the electrical supply.
The gas service cock is open.
Then follow the instructions below :
Press the On/Off button (1)
1
The pressure must be between 1 and 2 bar. If not, the system must be filled by a competent person.
1.5
bar
To stop the boiler : Press button (1)
IO
1
mode
Hab 264
Setting to the WINTER position
(Heating + hot water)
Press the mode button to select the winter symbol
Appuyer sur mode pour sélectionner la position hiver
2
°C
10
The actual temperature
Température actuelle
of the heating system
dans le circuit chauffage
1.5
bar
Illuminates when
Apparaît lorsque le
the boiler lights
brûleur fonctionne
mode
Adjusting the heating temperature
Press + or - to adjust the maximum temperature
Appuyer sur + ou - pour ajuster la température
of the heating (38°C to 87°C)
maximale souhaitée du circuit chauffage
Visual indication of set temperature
Visualisation de la température demandé
● Adjust heating temperature to maximum .
● Check that any external controls, if fitted, are
calling for heat (set room thermostat to maximum).
● Allow the temperature to rise to the maximum
value, with all radiator valves open. The temperature rise will cause release of the gases contained
in the water of the central heating system.
● Gases driven towards the boiler will be automati-
cally released through the automatic air vent.
● The gases trapped at the highest point of the sys-
tem must be released by bleeding the radiators.
On reaching maximum temperature, the boiler
should be turned off and the system drained as
rapidly as possible whilst still hot.
● Refill system to a pressure of between 1 and 2
bar and vent as before.
● Restart boiler and operate until a maximum tem-
perature is reached. Shut down boiler and vent
heating system. If necessary, top up heating system and make sure that a pressure of at least 1 bar
is indicated when system is COLD.
3
60
°C
mode
Hab 261
17
Page 18
COMMISSIONING
Setting the heating output
The heating output can be set without the use of a
pressure gauge; proceed as follows:
● Press the display light button
and keep pressed for 5 seconds, see diagram 20.
Note:The boiler has now been put into 'Service
Mode', allowing certain adjustments to be made
and diagnostic fault codes to be displayed. Refer
to the 'Servicing Instructions' for further details.
The heating output, in kW , is shown on the left hand
side of the display, see diagram 21.
● Remove the blanking plug from the front of the
control panel to gain access to the heating adjusting screw.
● Adjust the heating output by turning the screw
clockwise to increase, anti-clockwise to decrease.
● Refit blanking plug.
Note: Adjustment of the heating output does not
affect the domestic hot water output.
For kW to Btu/hr conversion refer to table 5.
Table 5
kW to Btu/hr conversion
kWBtu/hr
1034,120
1240,940
1447,770
1654,590
1861,420
kWBtu/hr
2068,240
2275,060
2481,890
2688,710
2895,540
1
Diagram 20
Adjustment screw
Diagram 21
Setting the heating output
2
mode
2001
5 s
Reg 051/UK
Setting the heating output
The heating output, in kW ,
is shown on the display.
Reg 052
kWBtu/hr
30102,360
32109,180
34116,000
35119,420
Setting the maximum heating temperature
The maximum heating temperature can be preset
at commissioning stage to suit the type of heating
system.
For example, for use with underfloor heating, the
maximum heating temperature can be set to 53°C.
To adjust the maximum temperature, proceed as
follows:
Remove the blanking plug (b) from the rear of
the control panel to gain acess to selector switch
SW1 (see diagram 22).
Adjust toggles 1 and 2 to give the desired maximum heating temperature, see diagram
Note: T o adjust the maximum heating temperature
it is only necessary to change toggles 1 and 2. Do
NOT touch any other toggles.
cates fault conditions, should they occur.
In the event of a fault, the display will indicate, by
means of pictograms and/or letters and numbers,
exactly in which area the fault lies.
18
incorporates a visual display that indi-
Should the boiler fail to operate during Commissioning, the most likely fault is that the gas supply
to the boiler has not been turned on or purged sufficiently or that there is no pressure in the heating
system. These are indicated as follows :
Page 19
SAFETY DEVICES
No gas supply
This will be indicated
➜
on the display as a
pictogram of a spark.
To rectify this, proceed as follows:
Switch off the boiler at the On/
Off push button.
Rectify the gas supply problem.
Restart the boiler by pressing the
On/Off button.
IO
1
--------------------------
Insufficient system pressure
This will be indicated
on the display as a
0.3
bar
To rectify this the system must be re-filled, refer to
'Commissioning'.
flashing warning indicating the system
pressure is low.
--------------------------
Other faults
These are indicated on the display by a fault code
and a telephone symbol. Further information on the
fault codes can be found in the 'Servicing Instruc-
tions'.
General safety devices
Air flow rate safety device
If an obstruction, even partial, of the flue occurs,
for any reason whatsoever, the built in safety system of the boiler will turn the boiler OFF and the
fan will continue to run.
The boiler will be ready to operate when the fault
has been cleared.
Overheat safety
In case of boiler overheating, the overheat thermostat will turn the boiler off. The thermostat, located on the heat exchanger flow pipe, will need
to be manually reset.
In case of power supply failure
The boiler no longer operates.
As soon as power supply is restored, the boiler will
be automatically restarted.
Frost protection
The ISOMAX has a built in frost protection device
that protects the boiler from freezing. If the boiler is
to be left and there is a risk of frost, ensure that the
gas and electrical supplies are left connected. The
frost protection device will light the boiler when the
temperature of the boiler water falls below 6°C.
When the temperature reaches 16°C, the boiler
stops.
Note : This device works irrespective of any room
thermostat setting and will protect the complete
heating system.
CHANGING GAS TYPE
Should it become necessary to change the gas
type, a modification kit will be required.
This modification must only be carried out by a
suitably qualified engineer.
Conversion natural Gas (G20) to G30/G31 Part No.
86216.
19
Page 20
SETTINGS
Gas valve setting
All boilers are tested and factory set during manufacture. Should it be necessary to reset a gas valve,
for example, after replacement, proceed as follows:
Shut down boiler.
Minimum setting
Remove one electrical connector from the
modulating gas valve coil, see diagram 23.
Connect a suitable pressure gauge.
Set the OFF/Summer/Winter switch to the ‘Sum-
mer’ position.
Adjust the domestic hot water temperature ad-
juster to maximum setting.
Remove the protective cover from the gas valve
adjuster.
Turn nut ‘A’, see diagram 23:
CLOCKWISE: To increase the pressure.
ANTICLOCKWISE: To decrease the pressure.
Maximum setting
Reconnect the electrical connector removed
from the modulating gas valve coil.
Remove the protective cover from the gas valve
adjuster.
Turn nut ‘B’, see diagram 23:
CLOCKWISE: To increase the pressure.
ANTICLOCKWISE: To decrease the pressure.
After adjustment, refit the cover to the gas valve
adjuster.
Diagram 23
MODULATING COIL
Electrical
connection
Reg 020
a
Bypass
The
ISOMAX
has a built-in bypass. This must be adjusted according to the requirements of the system,
refer to the flow rate pressure curve (diagram 4).
The boiler is supplied with the built-in bypass open
a half a turn. It is adjusted by turning the bypass
screw (a), seediagram 24. Turn the screw clockwise to close the bypass.When using thermostatic
radiator valves (TRV’s) on all of the radiators, it is
essential that a separate, adjustable bypass of 15
mm minimum diameter is fitted between the flow
and return of the heating circuit, see diagram 8.
Any bypass must be fitted before system controls.
Diagram 24
Reg 054
20
Page 21
ROUTINE CLEANING AND INSPECTION
To ensure the continued efficient and safe operation of the boiler it is recommended that it is
checked and serviced at regular intervals. The frequency of servicing will depend upon the particular installation conditions and usage, but in general once a year should be enough.
It is the law that any servicing is carried out by a
qualified registered person.
Service Check and Preparation.
• Operate boiler and check for any faults that need
to be put right.
• Isolate boiler from the gas and electrical supplies.
• On completion check all gas carrying parts for
soundness with leak detection fluid.
• Remove boiler casing as follows:
Upper front panel
• Remove the two front panel retaining brackets
from the top of the boiler.
• Remove panel by lifting up and forward.
Sealed chamber cover
• Unclip the toggle clip holding the sealed chamber cover, see diagram. 1.
• Lift cover up and off boiler.
Diagram 1
Car 033
Front control panel
• Lift control panel up and lower forwards to gain
access to lower part of boiler.
Side panels
• Unscrew and remove the four screws securing
lower grille onto boiler. Unhook grille from rear of
boiler and remove.
• Remove three screws from front of each side panel.
• Unclip the toggle clips securing top of each panel.
Lift each panel up and then forward to remove.
Combustion chamber cover
• Unscrew the three screws securing combustion
chamber cover to combustion chamber, see dia-gram 2.
• Remove combustion chamber cover from boiler .
• Undo, but do not remove, two burner support screws
at rear of burner chamber.
Burner
• Undo main gas supply nut from burner.
• Pull off the ignition and flame sense leads from the
gas valve remove burner from boiler by lifting up and
pulling forwards from keyhole slots.
Note: The washer between main burner and main
burner gas supply must be kept for use on
reassembly.
• Remove ignition and flame sense electrodes from
burner.
• Unscrew and remove injector bar retaining
screws and separate injector bar from burner.
• Examine and clean injectors as necessary.
Note: DO NOT use a wire or sharp instrument on
the holes.
Clean burner by washing in soapy water. Dry thoroughly before re-fitting.
Diagram 2
Heat exchanger
• Disconnect power supply leads and earth lead
from fan.
• Unscrew and remove, two fan retaining screws
at front edge of fan mounting plate.
• Remove fan with mounting plate attached by
pulling forwards out of boiler.
• Remove air pressure switch sensing tube from
sensing probe on flue hood.
• Unscrew and remove screws securing flue hood
to rear panel.
• Withdraw flue hood from boiler.
• Examine heat exchanger for any blockages or
build up of deposits.
• Clean heat exchanger with soft brush or vacuum
cleaner. Do not use any tool likely to damage
painted finish of heat exchanger.
Reassembly of parts removed for servicing
All parts are replaced in reverse order to removal.
Ech 052
21
Page 22
ROUTINE CLEANING AND INSPECTION
Flue system
• Check externally to make sure that flue is not
blocked
• Inspect flue system to make sure that all fittings
are secure.
Operation of fan
• Switch on electrical supply and turn on gas.
• Light burner by opening a hot water tap.
• Without sealed chamber cover in place, burner
should be automatically prevented from lighting
by air flow detection system.
• Refit sealed chamber cover.
• Check that fan operates when burner lights and
stops when it goes out.
Diagram 3
A
u
➜
v
➜
m
Cold water inlet filter
Drain down hot water circuit of boiler only, as fol
lows:
• Close isolating valve/throttle (m) on cold water
isolating cock, see diagram 3.
Note: This valve is closed when screwed fully clockwise.
• Open one or more hot water taps to drain boiler
circuit.
• Undo connecting nut from cold water inlet connection.
• Clean and inspect filter, replace if necessary.
• With both filter and restrictor in place, recon-
nect connecting pipe to inlet connection and
tighten.
• Fully open isolating valve/throttle on cold water inlet and check for leaks.
C
r
q
Pla 213
REPLACEMENT OF PARTS
For replacement of the following components it will
be necessary to remove boiler casing panels as described in ‘Routine Cleaning and Inspection’.
WARNING: Before commencing the replacement
of any component, isolate appliance from electrical supply and turn off gas at service cock.
To replace domestic hot water thermistor
• Locate domestic hot water thermistor on hot water flow pipe on right hand side of boiler adjacent
to gas valve.
• Unclip thermistor from pipe.
• Disconnect leads from thermistor.
• Fit replacement thermistor.
• Fit leads to replacement thermistor, the polarity
is not important.
To replace central heating thermistor
• Locate central heating thermistor on heating flow
pipe on centre of boiler.
• Unclip thermistor from pipe.
• Disconnect leads from thermistor.
• Fit replacement thermistor.
• Fit leads to replacement thermistor, the polarity
is not important.
To replace storage vessel thermistor
For this operation the boiler must be removed from
the wall.
• Drain down heating and hot water circuit of the
boiler only, as follows:
• Close isolating valves (q) and (v) on central heat-
ing isolating cocks (A) and (C), see diagram 3.
Note: These valves are closed when slots are at right
angles to direction of flow.
• Drain boiler by opening drain valves (r) and (u),
see diagram 3.
Note: It is not necessary to drain down entire heat-
ing system to carry out this work.
• Close isolating valve/throttle (m) on cold water
isolating cock, see diagram 3.
Note: This valve is closed when screwed fully clockwise.
• Open one or more hot water taps to drain boiler
circuit.
• Disconnect flue system.
• Disconnect boiler pipes onto fixing jig.
• Disconnect mains cable and any external con-
trols cables.
• Remove boiler from wall.
• From rear of boiler, disconnect domestic pipes
from storage vessel.
• Disconnect electrical connections from vessel.
• Unclip vessel from boiler frame and remove from
boiler.
• Slide off plastic strap and separate two halves of
vessel insulation.
• Locate thermistor at top of insulation.
• Replace thermistor in same position as old ther-
mistor.
• Refit vessel in reverse order to removal.
• Refit boiler onto fixing jig, tighten all connections
ensuring that all sealing washers are fitted before
tightening.
• Reconnect flue making sure that all joints are
properly connected.
22
Page 23
REPLACEMENT OF PARTS
• Open isolating valves on flow and return connections, refill, vent and pressurise boiler.
• Check for leaks.
• Reconnect all electrical connections and restore
electrical supply.
• Open gas cock, operate boiler and re-check all
joints for soundness.
To replace fan
• Remove fan as described in ‘Routine Cleaning
and Inspection’.
• Fit replacement fan in reverse order to removal.
• Reconnect electrical leads.
To replace air pressure switch
• Locate air pressure switch situated inside sealed
chamber on top right hand side.
• Remove air pressure switch tube from sensing
probe on flue hood.
• Disconnect air pressure switch electrical connections.
• Undo screws on top of boiler securing air pressure switch to boiler and remove switch.
• Pull sensing tube off switch.
• Fit replacement switch to boiler in reverse order
to removal, noting that pressure sensing tube fits to
left hand connection on switch.
let pipe to flow sensor and carefully remove from
sensor.
• Pull out slotted metal clip securing flow sensor to
pump mounting and carefully remove sensor from
boiler.
• Fit replacement sensor to boiler in reverse order
to removal.
To replace printed circuit board (PCB)
• Gain access to rear of control panel.
• Unclip and remove external controls/mains con-
nection access cover.
• Unclip side clips and hinge up control panel cover
to gain access to PCB, see diagram 5.
• Carefully pull off electrical connections to PCB.
• Unclip and lift out PCB.
• Fit replacement PCB in reverse order to removal.
Note: 1) Make sure that PCB connections are fully
pushed onto replacement PCB.
2) Set the heating temperature option to the
same value as the old PCB, refer to 'Installation and
User' instructions.
To replace domestic water flow sensor
• Drain down hot water circuit of boiler only as described previously.
• Undo connecting nut from cold water inlet connection.
• Locate flow sensor on cold water inlet pipe to
boiler inside controls area, see diagram 4.
• Carefuly pull off electrical connector from flow
sensor.
• Pull out slotted metal clip securing cold water in-
Diagram 4
➜
Ins 104
Diagram 5
Acc 010/Acc011
23
Page 24
REPLACEMENT OF PARTS
To replace pump
• Drain down heating circuit of the boiler only, as
described previously.
Note: It is not necessary to drain down entire heating system to carry out this work.
• Undo two fixing screws and remove pump retaining bracket from front of pump.
• Undo clips securing pump outlet hose connection to pump.
• Slide hose along pipe to clear pump outlet.
• Disconnect pump electrical connection from
PCB.
• Transfer automatic air vent to replacement pump
using new washers supplied.
• Re-connect electrical connection to PCB.
• Fit replacement pump in reverse order to re-
moval.
• Open isolating valves on flow and return connections, refill, vent and pressurise boiler.
• Check for leaks.
To replace domestic hot water heat exchanger
• Drain down heating and hot water circuits of
boiler only as described previously.
Note: It is not necessary to drain down entire heating system to carry out this work.
• Unscrew and remove cold water inlet pipe from
fixing jig to water flow sensor.
• Supporting domestic heat exchanger, unscrew
and remove two screws securing it onto pump
mounting and 3-way valve/bypass housing.
• Remove heat exchanger from boiler.
• Fit replacement heat exchanger in reverse order
to removal using new seals, supplied.
Note: Heat exchanger mounting screws are offset
to ensure correct fitting of replacement.
pipe from 3-way valve/bypass housing to storage
vessel.
• Undo pipe from 3-way valve/bypass housing to
fixing jig.
• From underneath boiler, undo two screws securing 3-way valve/bypass housing and lift out of
boiler.
• Fit replacement 3-way valve/bypass housing in
reverse order to removal.
To replace system pressure sensor
• Drain down heating circuit of boiler only as described previously.
Note: It is not necessary to drain down entire heating system to carry out this work.
• Locate system pressure sensor at front left hand
side of boiler, see diagram 8.
• Remove electrical connections from sensor.
• Pull off slotted metal clip and remove sensor from
boiler.
• Fit replacement sensor in reverse order to removal.
To replace gas valve module
• Locate gas valve module attached to side of gas
valve.
➜
Diagram 6
Pho483
To replace 3-way valve head
• Locate 3- way valve in centre of lower controls
area.
• Remove electrical plug from valve head.
• Pull out slotted metal clip from valve body and
remove valve head from body.
• Fit replacement valve head in reverse order to
removal.
Note :
1) When refiting clip, ensure that letters OK are asshown in diagram 6.
2)It is not necessary to drain boiler to carry out this
work.
To replace 3-way valve/bypass housing
• Drain down heating and hot water circuit of boiler
only as described previously.
Note: It is not necessary to drain down entire heating system to carry out this work.
• Remove 3-way valve head as described previously.
• Remove domestic hot water heat exchanger as
described previously.
• Undo pipe connection from 3-way valve/bypass
housing to primary heat exchanger, see diagram 7.
• Pull out slotted metal clips and remove bypass
pipe.
• Pull out slotted metal clip and remove domestic
Diagram 7
Diagram 8
Pho484
Pho485
24
Page 25
REPLACEMENT OF PARTS
➜
➜
Diagram 9
• Remove screw securing cover onto gas valve
module, see diagram 9.
• Remove cover and disconnect multi-plug from
module.
• Disconnect ignition and flame sense leads from
module.
• Withdraw module from gas valve.
• Fit replacement module, ensuring it is of the cor-
rect type for the boiler , in reverse or der to removal.
• Reconnect ignition and flame sense leads, the
connections are uniquely sized to ensure correct
replacement.
• Reconnect multi-plug onto replacement module.
• Refit cover ensuring all sealing grommets are cor-
rectly located in module body.
To replace gas valve
• Ensure that gas supply to boiler is turned off at
gas cock.
• Remove gas valve module as described previously.
• Disconnect electrical connections to gas valve
modulating coil, see diagram 9.
• Undo main gas supply nut from main burner.
Note: The washer must be kept for use on
reassembly.
• Undo main gas union nut between gas valve supply pipe and gas inlet valve.
Note: The washer must be kept for use on
reassembly.
• Disconnect plastic sensing pipe from gas valve
to base of sealed chamber.
• Unscrew and remove screws securing gas valve
bracket to boiler frame.
• Withdraw gas valve assembly.
• Using old gas valve as a guide, transfer gas pipes
from old gas valve to replacement gas valve.
• Fit replacement gas valve into boiler.
• Reconnect gas pipes in reverse order to removal.
• Refit electrical connections in reverse order to re-
moval, the polarity of the wires to the modulating
coil is not important.
To replace modulating coil
• Ensure that gas supply to boiler is turned off at
gas cock.
• Disconnect electrical connections to gas valve
modulating coil, see diagram 9.
• Undo two screws securing modulating coil to gas
valve and remove coil.
Mec 140
• Fit replacement coil in reverse order to removal.
• Refit electrical connections in reverse order to re-
moval, the polarity of the wires to the modulating
coil is not important.
To replace central heating safety valve
If safety valve seating is damaged, it will be necessary to replace safety valve as a complete unit,
repair is not possible.
• Drain down heating circuit of boiler only as described previously.
• Disconnect safety valve discharge pipe from
safety valve.
• Remove wire clip securing safety valve to fixing
jig and remove safety valve, see diagram 10.
• Fit replacement safety valve in reverse order to
removal.
Note: Apply a small quantity of silicon grease to
the safety valve 'O' ring prior to fitting.
• Open isolating valves on flow and return connections, refill, vent and pressurise boiler.
• Check for leaks.
To replace storage vessel safety valve
If safety valve seating is damaged, it will be necessary to replace safety valve as a complete unit,
repair is not possible.
• Drain down hot water circuit of boiler only as described previously.
• Disconnect safety valve discharge pipe from
safety valve.
• Remove wire clip securing safety valve to fixing
jig and remove safety valve, see diagram 10.
• Fit replacement safety valve in reverse order to
removal.
Note: Apply a small quantity of silicon grease to
the safety valve 'O' ring prior to fitting.
Diagram 10
➜
• Open isolating valve on cold water inlet connection.
• Check for leaks.
To replace heat exchanger
• Drain down heating circuit of boiler only as described previously.
Note: It is not necessary to drain down entire heating system to carry out this work.
• Remove combustion chamber cover, as described in ‘Routine Cleaning and Inspection'.
• Disconnect electrical connector from high limit
thermostat.
➜
214
Pla
25
Page 26
REPLACEMENT OF PARTS
• Remove slotted metal clips from heat exchanger connection pipes.
• Undo nut securing pipe from heat exchanger to 3way valve/bypass housing.
• Swing pipe away from 3-way valve/bypass housing
and pull down to disengage from heat exchanger pipe.
• Pull down pipe from pump to heat exchanger to disengage from heat exchanger pipe.
• Slide heat exchanger forwards and remove from
boiler, see diagram 11.
• Fit replacement heat exchanger in reverse order to
removal.
• Reconnect electrical connector to high limit thermostat.
• Open isolating valves on flow and return connections,
refill, vent and pressurise boiler .
• Check for leaks.
Diagram 11
To replace central heating expansion vessel
Replacement of the expansion vessel is not possible with the boiler on the wall.
Remove boiler from wall as described in 'To replace
storage vessel thermistor'.
• Undo pipe coupling on expansion vessel.
• Supporting expansion vessel, unscrew and re-
move screw securing expansion vessel to boiler.
• Lift vessel out of boiler.
• Fit replacement vessel to boiler in reverse order
to removal, ensuring that sealing washer is fitted to
pipe connection before tightening.
• Ensure that expansion vessel charge pressure is
0.5 bar (7.5 psi) using a pressure gauge. If necessary, increase pressure using a car or cycle tyre
pump connected to the Schrader valve.
• Refit boiler onto fixing jig, tighten all connections
ensuring that all sealing washers are fitted before
tightening.
• Reconnect flue making sure that all joints are
properly connected.
• Open isolating valves on flow and return connections, refill, vent and pressurise boiler.
• Check for leaks.
• Reconnect all electrical connections and restore
electrical supply.
• Open gas cock, operate boiler and re-check all
joints for soundness.
Ech 040
To replace combustion chamber insulation
• Remove combustion chamber cover as described in ‘Routine Cleaning and Inspection’.
• Remove heat exchanger as described previously.
• Remove fan and flue hood as described in ‘Rou-
tine Cleaning and Inspection’.
Front panel:
• Lift front insulation panel free from retaining lugs
on combustion chamber cover.
Rear panel:
• Pull rear insulation panel free from retaining lug
at rear of combustion chamber by tilting forward.
• Fit replacement insulation panels in reverse order to removal
• Refit combustion chamber cover.
Side panels:
• Pull out side panels.
To replace burner
• Remove burner as described in 'Routine Cleaning and Inspection'.
Assemble replacement burner , supplied in parts, as
follows:
• Fit burner injectors to burner injector bar and
tighten.
Note: Make sur e that injector size, marked on each
injector , is the same as that given in ‘T echnical Data’
for the type of gas being used.
• Fit injector bar into burner , secure with retaining rods.
• Fit replacement burner into boiler in reverse or-
der to removal.
To replace burner injectors
• Remove burner as described in 'Routine Clean-
ing and Inspection'.
• Pull out injector bar retaining rods and separate
injector bar from burner.
• Unscrew and remove injectors from injector bar.
• Fit replacement injectors to injector bar and
tighten.
Note: Make sure that injector size, marked on each
injector , is the same as that given in ‘T echnical Data’
for the type of gas being used.
• Reassemble burner and fit into boiler in reverse
order to removal.
To replace ignition electrode
• Remove burner as described in ‘Routine Cleaning and Inspection’.
• Undo and remove screw securing electrode onto
burner.
• Fit replacement electrode onto burner in reverse
order to removal.
• Refit burner into boiler in reverse order to removal.
To replace high limit thermostat
• Locate high limit thermostat on heating flow pipe
on left hand side of boiler.
• Disconnect electrical connection from thermostat
• Unclip thermostat from heating flow pipe.
• Fit replacement thermostat in reverse order to re-
moval.
• Refit connection to thermostat.
26
To replace flame sense electrode
• Remove burner as described in ‘Routine Cleaning and Inspection’.
• Undo and remove screw securing electrode onto
burner.
• Fit replacement electrode onto burner in reverse
order to removal.
• Refit burner into boiler in reverse order to removal.
A-Heating return
B-Cold water inlet
C-Heating flow
D-Domestic hot water outlet
E-Gas
D1 - Discharge from HTG safety valves
D2 - Discharge from DHW safety valves
D3 - Discharge from temp/press (to tundish)
12
19
25
21
22
16
18
15
11
7
20
17
14
13
1028
27
6
9
5
8
3
4
2
26
24
1
Diagram 12
ABCDE
D1
D1
D2
D1
D3
D1
Shy 163cUK
27
Page 28
TECHNICAL DATA
Heating
Heating outputajustable from 10,1 kW
to 27,6 kW
from 35,484 BTU/H
to 94,170 BTU/H
Efficiency91 %
Maximum heating temperature87 °C
Expansion vessel effective capacity8 l
Expansion vessel charge pressure0,5 bar
Maximum system capacity at 75°C180 l
Safety valve,maximum service pressure 3 bar
Products outlet diameter60 mm
Fresh air inlet diameter100 mm
Hot water
Hot water output, automatically variable from 10,4 kW
to 27,6 kW
from 35,484 BTU/H
to 94,170 BTU/H
Maximum hot water temperature60 °C
Specific flow rate (for 30°C temp rise)13,2 l/min.
Threshold flow rate1 l/min.
Nominal water flow rate11,3 l/min.
Maximum supply pressure8 bar
Minimum operating pressure0,7 bar
Electrical supply230 V
Maximum absorbed power235 W
Level of protectionIP44
Natural Gas (G20)
Ø Burner injector1,20 mm
Inlet pressure20 mbar
Maxi. Burner pressure13,8 mbar
Mini. Burner pressure2,16 mbar
Gas rate maximum3,20 m3/h
Gas rate minimum1,32 m3/h
Butane Gas (G30)
Ø Burner injector0,77 mm
Inlet pressure29 mbar
Maxi. Burner pressure23,8 mbar
Mini. Burner pressure3,6 mbar
Gas rate maximum2,39 kg/h
Gas rate minimum0,99 kg/h
Propane Gas (G31)
Ø Burner injector0,77 mm
Inlet pressure37 mbar
Maxi. Burner pressure30,8 mbar
Mini. Burner pressure3,6 mbar
Gas rate maximum2,35 kg/h
Gas rate minimum0,97 kg/h
Bypass fully shut
1
Open 1/4 turn
2
3
Open 1/2 turn
Open 1 turn
4
Open 2 turns
5
Bypass fully shut
1
Open 1/4 turn
2
60
50
40
1
2
3
4
5
30
20
10
heating supply and return lines
Available pressure (kPa) between
0
(10 kPa = 1 m WG)
345
Open 1/2 turn
120010008006004002000
Flow rate through heating system (I/h)
Open 1 turn
Open 2 turns
Pom 010 a
28
Page 29
SCHEMATIC WIRING DIAGRAM
B6.1
B6.3
B6.4
B6.2
B2.4
H6.1
H6.2
h8.1
h8.2
h4.1
Opt.
L
N
M/A
Ps
h4.3
h3.1
Ex
h3.3
h1.1
P
h1.2
h2.4
h2.2
h2.3
h2.5
h2.1
h5.2
h5.3
h5.1
B2.8
B2.7
ACF
Flam
K4
CH
V
89
Ph11N10DA
1
2
3
COM
V
SAN
B8.1
B8.2
B3.3
B1.2
B2.9
B2.8
B2.11
B1.13
B1.15
B1.7
B1.8
B1.10
B3.1
B3.2
B3.3
B3.4
B2.6
B2.5
B1.5
B1.6
B1.4
B1.3
b5.1
b5.2
b5.4
b5.5
HL
Db
+
CTN 3
V1
P
J1
CTN 2
CTN 1
Cp
Pr
1
TA
2
3
Ra
4
5
B4.1
B4.2
FAFL
INTERFACE
M/A- on/ off
Ps- domestic water pump
P-heating pump
ACF- ignition card and flame control
SAN- hot water
INTERFACE - User interface
Db- output detector
Cp- water pressure sensor
V1- gas mechanism modulating valve
J1- connector for room temp. thermostat
TA- room temperature thermostat
B4.3
B4.4
B3.5
CD
B3.6
B7.3
SE
B7.2
+
B7.1
B2.4
B2.1
B2.2
GNDSVe
VitesseExtracteur(option)
Ra- room temp. thermostat anticipation resistor
FA- ignition electrodes
FL- ionisation electrode
CTN1- hot water thermistor
CTN2- heating thermistor
CTN3- accumulator thermistor
K4- overheating safety
Pr- air pressure switch
Ex- fan
accessories
Opt- option card
CD- remote control
SE- external sensor
HL- clock
Diagram 14
sch292
29
Page 30
FAULT FINDING
Before trying to operate the boiler make sure that :
• All gas supply cocks are open and that the gas
supply has been purged of air.
• The heating system pressure is at least 1 bar.
• There is a permanent mains supply to the boiler .
• The fuse on the PCB is intact.
WARNING. Always isolate the boiler from the electrical supply before carrying out any electrical replacement work.
Always check for gas soundness after any service
work.
Table 1
VoltageMeasured valueMeasuring point
230 Volt230 V ACBetween terminals H8.1 and H8.2
24 Voltmaximum 33V DCBetween terminals B2.4 and B2.7
minimum 20V DC
Should there be any doubt about the voltage supply to any of the components, it is possible to carry
out a simple electrical test to ensure all is operational in that area.
To carry out the electrical test, gain access to the
main Printed Circuit Board (PCB), as described previously, and measure the voltages according to
table 1.
15 Volt15V + 0.5VBetween terminals B2.4 and B2.2
Display5V + 0.5VBetween terminals B2.4 and B4.2
ISOF AST
The
the top of the user displaywill illuminate and the LCD display will indicate the precise area where the
fault has occured.
has an on-board fault diagnostic system. Should a fault occur on the boiler, the warning LED at
09FF
Sec 052
A fault code is displayed on the left hand side of the LCD display, whilst at the same time, the letters
appear with a telephone symbol.
FF
30
Page 31
FAULT FINDING
List of fault codes
CodeFaultAdditional display
00No fault
02Air flow fault
04Ignition fault -flame detection
05Overheating
06Central heating thermistor/wiring fault
07Domestic hot water thermistor/wiring fault
08Storage vessel thermistor/wiring fault
09System pressure sensor fault
information
10Fan fault
11Pump blockage
12User interface fault
13Main PCB fault
14CTN2 > 97°C - pump will run
15Gas mechanism fault
20Communication fault
31
Page 32
FAULT FINDING
Thermistor values
The following table applies to the central heating,
domestic hot water and storage vessel thermistors:
Temperature (°C)Resistance (Ω)
0......................................32565
5......................................25345
10.....................................19875
15.....................................15700
20.....................................12500
25.....................................10000
30......................................8060
35......................................6535
40......................................5330
45......................................4370
50......................................3605
55......................................2989
60......................................2490
65......................................2085
70......................................1755
75......................................1480
80......................................1260
85......................................1070
90.......................................920
95.......................................785
100......................................680
System pressure sensor
The resistance of the sensor at various pressures is
as follows :
0 bar ...................... between 280 Ω and 320 Ω
1 bar ...................... between 195 Ω and 220 Ω
3 bar ...................... between 93 Ω and 143 Ω
SPARE PARTS
When ordering spare parts, quote the part number and description, stating the appliance model number
and serial number from the data badge.
Short parts list
No. ......Description ...................................... Part No.
1 ..........Domestic hot water thermistor ..........57213