Saunier Duval SYLVA FF 24 E User manual

1
SYLVA
THIS IS A CAT II2H3+ APPLIANCE
01773 828100
IN WARRANTY
TECHNICAL HELPLINE
01773 828400

2
INSTALLATION AND OPERATING INSTRUCTIONS
USERS SECTION INSTALLATION SECTION
SYLVAFF24E
NOTE !
The boiler serial number is marked on the label attached to the inside of the side panel. Refer to the ‘intro-
duction’ section page 3 for a description of the basic functions of the boiler. The ‘users’ section describes
how to safely operate the boiler.
Introduction .......................................................Page 3
Commissioning ............................................................ 3
Controls & lighting ...................................................... 4
Draining........................................................................ 4
Servicing/maintenance ............................................. 4
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
Introduction ....................................................... Page 3
Technical data .............................................................5
Dimensions ....................................................................6
Heating system design ................................................6
Domestic hot water system design ...........................6
Boiler schematic .......................................................... 7
Piping system installation ...................................... 8 - 9
Boiler location ............................................................10
Boiler installation ........................................................11
Flue installation ................................................... 11 - 12
Electrical connection ................................................13
Commissioning ................................................... 14 - 15
Operating safety devices .........................................15
Settings ........................................................................16
Changing gas type ...................................................16

3
INTRODUCTION
The SYLVA FF 24 E boiler is a wall mounted
combination boiler with electronic ignition
providing central heating and an unvented hot
water storage of 60 litres.
The boiler is of the II2H3+ category for use with
Natural Gas (G20) as distributed in the United
Kingdom, or Butane (G30), Propane (G31) with the
appropriate conversion kit.
Conversion kits:
Conversion Part No.
Natural Gas (G20) to LPG (G30/G31) 85402
Boilers burning LPG or similar gases MUST NOT be
fitted in basements or below ground level.
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.
Electrical components have been tested to meet
the equivalent requiments of BEAB.
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.
The installation must be carried out by a competent
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.
Ancillary equipment
A range of flue accessories are available including
vertical flues, twin-pipe flues, bends etc.
For further information contact your supplier.
Diagram 1
A - Reset button
B - Reset indicating light
C - Mains ON light
D - Domestic hot water temperature control
bar
0
bar
2
1
0
3
4
50
40
20
0
80
100
120
°C
A B C D E F G H
COMMISSIONING
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 competent 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.
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.
Hab 244
E - OFF/Summer/Winter selector switch
F - Central heating temperature control
G - Pressure gauge
H - Temperature gauge

4
CONTROLS AND LIGHTING
Starting the boiler
Before starting the boiler, make sure that:
●The boiler is connected to the electrical supply
and turned on.
●The boiler gas service cock is open.
●The pressure gauge reads between 1and 2bar.
The boiler is now ready to start
Setting to WINTER mode (Heating and hot water)
●Turn the OFF/Summer/Winter selector switch (E) to
the ‘Winter’ position, see diagram 1.
●Turn the central heating temperature control (F)
to the desired setting, see diagram 1.
●Turn the domestic hot water temperature control
(D) to the desired setting, see diagram 1.
●Make sure that any external controls are calling
for heat.
The boiler will light and proceed to heat up the
integral storage cylinder, after which time, up to
approximately 10 minutes depending on the setting
of the temperature control, the heating system will
begin to heat up.
NOTE: Once the cylinder has reached its’ set tem-
perature, the boiler will continue to operate in heat-
ing mode until the cylinder needs topping-up again.
To obtain domestic hot water, open a hot water tap.
Hot water always has priority over central heating.
Setting to SUMMER mode (Hot water only)
●Turn the OFF/Summer/Winter selector switch (E) to
the ‘Summer’ position, see diagram 1.
●Turn the domestic hot water temperature control
(D) to the desired setting, see diagram 1.
The boiler will light and proceed to heat up the in-
tegral storage cylinder, after which time, up to ap-
proximately 10 minutes depending on the setting
of the temperature control, the boiler will stop.
NOTE: Once the cylinder has reached its’ set tem-
perature, the boiler will remain off until the cylinder
needs topping-up again.
To obtain domestic hot water, open a hot water tap.
Hot water always has priority over central heating.
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 SYLVA 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 and that
the OFF/Summer/Winter switch is left in the ‘Summer’
or the ‘Winter’ position. 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 only protects the boiler.
Always ensure that adequate frost protection is
given to the entire system where necessary.
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 safety valve with a discharge pipe is
fitted to this boiler.
The valve MUST NOT BE TOUCHED except by a com-
petent person. If the valve discharges at any time,
switch the boiler off and isolate it from the electrical
supply. Contact your installation/service company.
Temperature/pressure relief valve
CAUTION: A temperature/pressure relief valve with
a discharge pipe into a tundish is fitted to this boiler.
The valve MUST NOT BE TOUCHED except by a com-
petent person. If the valve discharges at any time,
switch the boiler off and isolate it from the electrical
supply. Contact your installation/service company.
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. In particular, the
anode fitted to the domestic hot water storage
cylinder must be checked at least once a year and
replaced as necessary.
The frequency of servicing will depend upon the
installation conditions and usage but, in general,
once a year should be enough.
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
Heat output
(kW) 10,8 11 12 13 14 15 16 17 18 19 20 21 22 23 24
(Btu/h) 36850 37532 40944 44356 47768 51180 54592 58004 61416 64828 68240 71652 75064 78476 81888
Heat input
(kW) 13,9 14,1 15,3 16,6 17,8 19,0 20,2 21,4 22,6 23,8 24,9 26,1 27,3 28,4 29,6
(Btu/h) 47389 48115 52326 56510 60668 64800 68907 72989 77045 81077 85084 89067 93026 96961 100872
GAS
G 20 (mbar) 3,1 3,4 3,5 4,1 4,7 5,4 6,1 6,8 7,6 8,4 9,2 10,1 11,1 12,0 13
G 30 (mbar) 5,8 6,3 6,9 8,1 9,3 10,6 12,0 13,5 15,0 16,6 18,3 20,0 21,9 23,7 25,7
G 31 (mbar) 7,6 8,0 9,1 10,6 12,3 14,0 15,8 17,7 19,8 21,9 24,1 26,4 28,8 31,3 33,9
TECHNICAL DATA
Heating output
adjustable from 10,8 kW to 24 kW
36,850 BTU/H to 81,890 BTU/H
Efficiency 81 %
Maximum heating temperature 90 °C
Expansion vessel effective capacity 7,5 l
Expansion vessel charge pressure 1,0 bar
Maximum system capacity at 75°C 170 l
Safety valve, maximum service pressure 3 bar
Products outlet Ø 60 mm
Fresh air inlet Ø 100 mm
Hot water output
automatically variable from 10,8 kW to 24 kW
36,850 BTU/H to 81,890 BTU/H
Storage capacity 60 l
Maximum hot water temperature 65 °C
Specific flow rate (for 30°C temperature rise) 13,6 l/min.
Nominal water flow rate 10 l/min.
Expansion vessel effective capacity 2 l
Expansion vessel charge pressure 3 bar
Maximum supply pressure 10 bar
Maximum operating pressure 3,5 bar
Temp./press. relief valve opening pressure 7 bar
Temp./press. relief valve opening temperature 90 °C
Cylinder heat up time 7 min.
Time to reheat 70% of storage to 65°C 3 min.
Expansion valve setting 6 bar
Weight when full 144 kg
Electrical supply 230 V
Maximum absorbed power 165 W
Level of protection IP44
Natural Gas Butane Propane
(G20) (G30) (G31)
Burner injector 1,20 mm 0,77 mm 0,77 mm
Inlet pressure 20 mbar 28 mbar 37 mbar
Gas rate (maximum) 2.81 m3/h 2,10 kg/h 2,06 kg/h
Gas rate (minimum) 1,32 m3/h 0,98 kg/h 0,97 kg/h
Gas (reference 15°- 1013 mbar)
Burner pressures : burner pressures, as listed in the table below, must be checked after the boiler has been
operating for 3 minutes.
Table 1
0
10
20
500 1000 1500
30
40
50
Pression disponible (kPa)
entre départ et retour chauffage
Débit dans le circuit chaufage (l/h)
(10 kPa = 1 mCE)
2400 rpm
2250 rpm
1900 rpm
1600 rpm
0
30
35
30 60 90 120 150 180 210 240
40
45
50
55
60
65
Température de soutirage en °C
Quantité d'eau soutirée en litres
Water draw off temperature in °C
Flow rate through heating system (l/h)
Available pressure between
heating flow and return (kPa)
10 kPa = 1 mWG
Diagram 3
Water draw off in litres
Pump : Domestic hot water production :
Temperature of cold water = 15°C
Temperature of stored water = 60°C
Drawing off at 12 l/min.

6
HEATING SYSTEM DESIGN
●The SYLVA is compatible with any type of
installation.
●Heating surfaces may consist of radiators,
convectors or fan assisted convectors.
●Pipe sectional areas shall be determined in
accordance with normal practices, using the
output/pressure curve (diagram 3). 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 500 l/h.
●The piping system shall be routed so as to avoid
any air pockets and facilitate permanent venting
of the installation. Bleed fittings shall be provided at
every high point of the system and on all radiators.
●The total volume of water permitted for the
heating system depends, amongst other things, on
the static head in the cold condition. The expansion
vessel on the boiler is pressurised at 1 bar
(corresponding to a static head of 5 m w.g.) and
allows a maximum system volume of 170 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 6.
●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 ESSENTIAL
that the system is thoroughly flushed prior to installing
the new boiler.
Filling the system
Provision must be made for filling the system at low
level. The use of a WRC approved filling loop is
strongly recommended, connected as shown in
diagram 6.
DOMESTIC HOT WATER SYSTEM DESIGN
●Copper tubing must be used for the domestic hot
water system. Unnecessary pressure losses should be
avoided.
●A flow restrictor limiting the flow through the boiler
to a maximum of 12 l/min is fitted to the boiler.
●A pressure reducing valve for the cold water inlet
is supplied, this is packed inside the boiler.
This valve is a necessary part of the unvented system
and MUST be fitted to the cold water supply see
diagram 6.
DIMENSIONS
The SYLVA is delivered in two separate packages:
- the boiler itself
- the flue system
Hab 242
Diagram 2
600
880
475
182 165
80100

7
BOILER SCHEMATIC
Diagram. 4
Shy 115UK
17 - Expansion valve (6 bar)
18 - Domestic expansion vessel
19 - Drain valve
20 - Fan
21 - Air pressure switch
22 - Temperature/pressure relief valve (7 bar)
23 - Tundish
24 - Non-return valve
A - Heating return
B - Cold water inlet
C - Heating flow
D - Domestic hot water flow
F - Gas supply
1 - 3-way valve
2 - Loss of water switch
3 - Pump
4 - CVI unit
5 - Gas valve
6 - Ignition electrode
7 - Injector manifold
8 - Flame detection electrode
9 - Heat exchanger
10 - Bleed valve
11 - Thermistor
12 - Expansion vessel
13 - Anode
14 - Cylinder
15 - Domestic thermostat
16 - Overheat safety thermostat
H
L
21
10
11
19
20
21
13
14
15
6
7
8
9
AB
CD
F
12
12
3
4
5
17
18
16
23
22
24
SYLVAFF24E

8
PIPING SYSTEM INSTALLATION
●Heating system connections - Pipe diam 22 mm
●Hot water system connections - Pipe diam 15 mm
●Gas connection - Pipe diam 22 mm
●Tundish connection - Pipe diam 22 mm
●Safety valve discharge - Pipe diam 22 mm
Water connection
Connect the copper tails and isolating cocks
supplied, to the boiler : see diagram 5. Connect
the system pipework to the boiler observing the
correct flow and return format shown in diagram
5.
Safety valve discharge
WARNING. It must not discharge above an
entrance or window or any type of public access
area.
Connect the safety valve discharge pipe to the
boiler, the discharge must be extended using not
less than 15 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.
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 competent person in accordance with the
above regulations.
Diagram 5
➞
F : Gas
➞
➞
C : Heating
flow
➞
D : Domestic hot
water flow
B : Cold
water inlet
➞
Pla 194UK
A : Heating
return
Flow restrictor, filter
and non return valve

9
PIPING SYSTEM INSTALLATION
,
,


500 mm max.
300 mm max.
Fixed grating
Trapped
gully
Discharge pipe (D2) from
tundish with continuous fall see
table on left for size examples
Tundish
Safety device e.g.
temperature relief valve
Discharge pipe (D1) from
temperature relief valve to tundish
Bypass
Boiler
Return
Additional
expansion
vessel
(if required)
Flow
control valve Drain point
Filling point
Minimum 22 mm diameter
Tundish
(supplied)
Pressure
reducing
valve
(supplied)
Heating
circuit
Hot
Cold supply
Tundish discharge
The SYLVA is delivered with the tundish fitted to the
boiler but must be piped to a suitable position
outside the building in accordance with Building
Regulations.
It is permissible to use copper or an appropriate
temperature resistant plastic pipe, such as HEP2O
for this, see diagram 6.
WARNING. It must not discharge above an
entrance or window or any type of public access
area.
Connect the safety valve discharge pipe to the
boiler, the discharge must be extended using not
less than 15 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.
The tundish outlet pipe must have a vertical section
of at least 300 mm before any bends or elbows in
the pipework.
G 1/2 15 mm 22mm up to 9 m 0.8 m
28 mm up to 18 m 1.0 m
35 mm up to 27 m 1.4 m
G 3/4 22 mm 28 mm up to 9 m 1.0 m
35 mm up to 18 m 1.4 m
42 mm up to 27 m 1.7 m
G 1 28 mm 35 mm up to 9 m 1.4 m
42 mm up to 18 m 1.7 m
54 mm up to 27 m 2.3 m
Valve outlet size Maximum resistance
allowed expressed as
a length of straight
pipe i.e. no elbows or
bends
Resistance
created by each
elbow or bend
Minimum size of
discharge pipe
D2 from tundish
Minimum size of
discharge to
tundish
Sizing of tundish discharge pipework D2
Diagram 6

10
50 min.
135
145
780
300300
50
290
Clearances
The position of the boiler must be such that there is
adequate space for servicing.
The recommended clearances are:
50 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, noting
that hanging bracket must be 780 mm above centre
line of pipework, making allowances for the necessary
clearances etc.
Note: It is permissible to install the boiler with reduced
clearances at the bottom and sides of the boiler
PROVIDING adequate consideration is given for
Servicing/Repairs at a later date. If any doubt exists,
contact Saunier Duval Technical Helpline 01773 828400.
●Mark position of the holes for the hanging bracket.
●Drill, plug and fix the hanging bracket to the wall
using suitable screws.
●Check that the hanging bracket is level.
●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.
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 7.
Important: When fitting a flue to the right hand side
of the boiler, the flue must be raised to clear the
anode in the top of the storage cylinder. To do this,
use the spacer, Saunier Duval part number 85812.
Cutting the flue hole
●Making allowance for the slope of the flue, cut hole
in external wall, preferably using a 115 mm core drill.
If necessary, make good at both the inner and outer
surface of the wall.
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 per metre of
BOILER LOCATION
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
Minimum dimensions (in mm) for the positioning of flue terminals
NC
D
M
AB
EF
G
IHL
Ven 060b
Diagram. 8
flue DOWNWARD towards the terminal. There must
NEVER be a downward incline towards the boiler.
Terminal position
The minimum acceptable spacings from the terminal
to obstructions and ventilation openings are shown
in diagram 8.
The boiler must be installed so that the terminal is
exposed to the external air.
Should any doubt exist as to the permissible position
of the terminal, contact the Saunier Duval Technical
Helpline 01773 828400.
Terminal guard
If a terminal guard is required, a suitable guard can
be obtained from your supplier, Saunier Duval part
number 85373.
Cupboard or compartment ventilation
The boiler can be fitted in a cupboard or
compartment as long as adequate permanent high
and low level ventilation is provided in accordance
with ventilation requirements.
Diagram. 7
Ins 056/UK

11
BOILER INSTALLATION
Statutory requirements
The installation of this boiler must be carried out by
a competent 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.
Installing the boiler
Prior to starting work, the system must be thoroughly
flushed using a propriety cleanser such as Sentinel
X300 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.
●Connect the system pipework to the boiler.
●Connect the tundish outlet to a suitable drain, refer
to Piping System Installation.
Top outlet flue - kit 85090
The boiler is only suitable for top outlet flue
connection.
Calculation of flue cutting lengths
●Measure wall thickness e (mm), see diagram 9.
●For right hand side flue, measure distance from
inside face of side wall to centre line of boiler and
subtract 435 to get dimension a (mm).
●For left hand side flue, measure distance from
inside face of side wall to centre line of boiler and
subtract 165 to get dimension a (mm).
●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 10.
When the dimension X measured on site is greater
than that given in table 2, a flue extension kit will be
required, refer to table 3 for details.
Extended flue
The horizontal flue is extended by using one or more
of the 1000 mm extension pipes, Saunier Duval part
number 85091. These are connected together by
push fit type joints, clamps and seals.
Calculation of flue cutting lengths for extended flue
●Using the correct number of extension kits as table
3, measure dimensions a and e, see diagram 9. Cut
both the inner and outer pipes to the dimensions
given in table 4
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.
ee a
aX
X
∆L1
∆L2
∆L1
∆L2
Diagram 9
Table 2 :
Flue cutting lengths
Cutting length (mm)
Flue option outer pipe inner pipe Comments
Top outlet e + 108 e + 192 maximum
rear flue wall thickness "e"
without
extension 808 mm
Top outlet e + a + 361 e + a + 429 maximum
side flue distance "X"
(right) without
extension 990 mm
Top outlet e + a + 91 e + a + 159 maximum
side flue distance "X"
(left) without
extension 990 mm
Flue option Dimension "X" N°of
extension kits
Side flue 991 to 1991 mm 1
(right or left) 1991 to 2991 mm 2
Hab 210UK
Table 3 :
Number of extension kits required
FLUE INSTALLATION

12
FLUE INSTALLATION
Table 4 :
Flue extension cutting lengths
Cutting length (mm)
Flue option outer pipe inner pipe Comments
Side flue e + a - 555 e + a - 555 maximum
(right) dimension "X"
without
extension 990 mm
Side flue e + a - 825 e + a - 825 maximum
(left) dimension "X"
without
extension 990 mm
Cutting length
Outer pipe
Inner pipe
Cutting length
Terminal end
Ven 089
Installation of flue assembly
●Fit rubber sealing collar (A) into groove at the outer
end of pipe (B).
●Fit outer pipe (B) into wall with groove to the
outside.
●Pull pipe inwards to bring rubber sealing collar hard
up against external wall, see diagram 12.
●Fit internal plastic flange (C) onto outer pipe. Push
along the pipe until engaged against internal wall.
●From inside, insert inner pipe (D) into outer pipe.
●Fit both ‘O’ rings (E) into the flue elbow (F), 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.
●Slacken the two screws and fit the clamp and seal
(G) onto the elbow.
●Take hold of the inner flue and push gently onto
the elbow outlet taking care not to tear the ‘O’ ring.
Important: If the flue has been cut, ensure that there
are no burrs that could damage the ‘O’ ring.
●Push the elbow clamp and seal over the outer flue.
●For flue systems less than 1 m long, leave the
restrictor (a) fitted in the fan outlet, see diagram 13.
●Remove the backing from the self adhesive gasket
(H) and carefully fit gasket to base of flue elbow.
●Fit elbow onto boiler and secure with the four
screws (I).
Diagram 10
A
B
C
D
E
F
G
H
I
Pho 088
Diagram 11
The standard flue kit 85090, see diagram 11, comprises :
- External rubber sealing collar ................................... A
- Outer pipe .................................................................. B
- Plastic flange .............................................................. C
- Inner pipe .................................................................... D
- 2 ‘O’ rings .................................................................... E
- Elbow ........................................................................... F
- Clamp and seal ......................................................... G
- Gasket ......................................................................... H
- Four screws ................................................................. I
Pho 087
Hab 243
Diagram 13
165
182
80
L
Restrictor (a) if L ≤1 m Seal
Diagram 12
Concentric flue system
The maximum permissible length (L) for the
concentric flue system is 3 m. For flue systems up
to 1 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 flue elbow used, the maximum
permissible length (L) must be reduced by 1 metre.

13
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
VOLTAGE BE APPLIED TO ANY OF THE TERMINALS ON
THE HEATING CONTROLS CONNECTION PLUG.
External controls
The SYLVA FF 24 E boiler is designed to operate at
maximum efficiency at all times. The boiler will run
at its’ maximum efficiency when connected to a
programmable electronic room thermostat. A
programmable room thermostat is available as an
accessory, Saunier Duval part number 40010. Please
contact your supplier.
The boiler will work for heating without a room
thermostat and/or timeswitch being connected
provided that the wire link fitted between the upper
two terminals of the connector (E) is left in place,
see diagram 14.
A 230V room thermostat can be used but do not
make any connection to the compensating resistor,
see diagram 14.
ON NO ACCOUNT must any electrical voltage be
applied to any of the terminals of the external
controls plug.
For use with a timeswitch or timeswitch and room
thermostat, see diagram 14.
Warning: This appliance must be wired in
accordance with these instructions. Any fault arising
from incorrect wiring cannot be put right under the
terms of the Saunier Duval guarantee.
Sch 151
Fig. 9a
E
Diagram 14
No external controls Room thermostat only Room thermostat and time clock
Factory fitted link
Voltage free room
thermostat Voltage free room
thermostat
Time clock
Do not
connect
Do not
connect
Green wire
Red wire
White wire
1
1
1
1
2
22
2
3
3
3
3
Warning :
- All external controls must be voltage free
- On no account must any external voltage be
appliedtoany of the externalcontrolsplug terminals
Sch 152
External control connector
Boiler's 230 V mains lead :
- brown wire : line / blue wire : neutral / yellow and green wire : earth
Warning : you must respect the line / neutral connections to the 230 V mains supply.

14
COMMISSIONING
The commissioning and first firing of the boiler must
only be done by a competent 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 15.
Filling the system
●Open the boiler isolating valves (a, b and c
diagram 16) and cap on automatic air vent on top
of boiler.
●Open bleed vent (item 10) on flow pipe to storage
tank, see diagram 4, until all the air has been
released from the boiler.
Important: If this procedure is not carried out
properly, the boiler will go into safety lock-out until
all the air has been purged.
●Bleed each radiator until a continuous jet of water
is obtained.
●Do not close automatic air vent cap on top of
boiler.
●Open various hot water taps to bleed system.
●Make sure that pressure gauge reads between 1
and 2 bar. Re-pressurise as necessary.
Important:
When venting air from boiler, do not touch the
schrader valve on the expansion vessel, it is NOT a
vent.
Starting the boiler
Before starting the boiler check that:
- The gas meter tap is open.
- The boiler gas service cock is open.
- The boiler is connected to the electrical supply.
First starting up
●Referring to ‘Instructions for Use’, set boiler to run
in central heating mode.
●Set boiler thermostat 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
automatically released through the automatic air
vent.
- The gases trapped at the highest point of the
system 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 1 bar and vent as
before.
●Restart boiler and operate until a maximum
temperature is reached. Shut down boiler and vent
heating system. If necessary, top up heating system
and make sure that a pressure of 1 bar is indicated
when system is COLD.
Gas inlet pressure test point
Modulation coil
Diagram. 15
Gas pressures
The main burner pressure should be checked during
commissioning to make sure the correct input is
obtained. Proceed as follows:
●Shut down boiler.
●Undo screws on gas inlet test points RMP and MP
below sealed combustion chamber, see diagram
17.
●Connect a suitable pressure gauge.
●Gain access to the rear of the control panel and
locate the range rating adjuster screw, see diagram
18.
●Start boiler as described in ‘Instructions for Use’
●Set selector switch to heating and hot water
position.
●Set boiler thermostat to maximum and check that
any external controls are calling for heat.
●Check that the reading on the gauge matches
that given in ‘Technical data’ for the type of gas
being used.
●Adjust the range rating adjuster screw as
necessary to obtain the desired input.
●Shut down boiler.
●Remove pressure gauge, tighten up test point
screws and check for gas soundness.
Pla 194/UK
Diagram 16
b
c
a
Reg 018

15
COMMISSIONING
●Using a ball point pen, clearly indicate on the data
label the value the boiler is set to.
Note: This adjustment does not affect the domestic
hot water output.
If measured burner pressure differs greatly from the
given figure, check the gas inlet pressure as follows:
●Shut down boiler.
●Remove screw from inlet test point on the side of
the gas valve, see diagram 15.
●Connect a suitable pressure gauge.
●Start boiler as described in ‘Instructions for Use’.
●Check that the inlet pressure reading matches that
given in ‘Technical Data’ for the type of gas being
used.
●Shut down boiler.
●Remove pressure gauge, tighten up test point
screws and check for gas soundness.
●If the gas pressure is incorrect, refer to the Fault
Finding section in ‘Servicing Instructions’.
●If the inlet pressure is below that given, the gas
supply pipework/meter must be checked and any
fault corrected.
●In the case of an LPG installation, check the
storage tank or cylinder, regulator and pipework.
OPERATING 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.
In case of power supply failure
The boiler no longer operates.
As soon as power supply is restored, the boiler will
be automatically restarted.
In case of loss of water in the system
CAUTION: The boiler is installed
as part of a sealed system
which must only be drained
and filled by a competent
person.
If the pressure shown on the pressure
gauge is less than 1 bar or the red loss of
water indicating light is ON, the system
must be filled up immediately. Call your Installation/
Servicing company.
Gas leak or fault
If a gas leak or fault exists or is suspected, turn the
boiler off and consult the local gas company or your
Installation/Servicing company.
Important notice: A central heating system cannot
operate satisfactorily unless it is properly filled with
water and unless the air initially contained in the
pipework has been properly bled off. If these
conditions are not satisfied, air noise will occur within
the system.
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.
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.
Frost protection
The SYLVA 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 and that
the OFF/Summer/Winter switch is left in the ‘Summer’
or the ‘Winter’ position. 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 only protects the boiler.
Always ensure that adequate frost protection is
given to the entire system where necessary.
bar
bar
2
1
0
3
4
Diagram 17
Reg 037
Reg 041
Diagram. 18

16
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 19.
●Connect a suitable pressure gauge as described
in ‘Commissioning’.
●Turn the OFF/Summer/Winter switch to the
‘Summer’ position.
●Turn the domestic hot water temperature adjuster
to maximum setting.
●Remove the protective cover from the gas valve
adjuster.
●Turn nut ‘A’, see diagram 19:
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 19:
CLOCKWISE: To increase the pressure.
ANTICLOCKWISE: To decrease the pressure.
After adjustment, refit the cover to the gas valve
adjuster.
Bypass
When using thermostatic radiator valves (TRV’s), 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 6. Any
bypass must be fitted before system controls.
Diagram 19
MODULATING COIL
CHANGING GAS TYPE
Should it become necessary to change the gas
type, a modification kit comprising injectors and
factory set gas valve will be required. This
85820 C 10/97
modification must only be carried out by a suitably
qualified engineer.
Reg 020