Chaffoteaux & Maury Centora green Manual

MAINTENANCE AND
SERVICE GUIDE
Fanned Flue Condensing
Combination Boiler
Heating and Storage Domestic Hot
Water
Dimensions
Technical data
Flue types:
C13: - C 33 - C 53
C
54 54 54 54
JKLMN I
88
JK
L
MN
232
235
32
Safety valve
center line
All dimensions in mm
Outer case dimensions :
- Width : 440 (minimum space required 450)
-Height : 850
-Depth : 24 kW : 380 30 kW : 405
212
360
67
737
850
50
ISafety valve outlet
JHeating flow
K D.H.W. flow
LGas supply
MCold water inlet
N Heating return
Heat gross input C/H maxi ............................ 9,2-27,8 kW 10,4-31,6 kW
Heat gross input DHW maxi.......................... 9,2-27,8 kW 10,4-31,6 kW
Heat output C/H 50°/30° maxi....................... 9-26 kW 10-30 kW
Heat output C/H 80°/60° maxi....................... 8-24 kW 9-28 kW
Heat output DHW maxi ................................. 8-24 kW 9-30 kW
C/H operating temperature............................ 80°C max 80°C max
C/H circuit pressures Min operating .............. 0,7 bar 0,7 bar
C/H circuit pressures Max operating ............. 2,5 bar 2,5 bar
DHW flow rates 30°C.................................... 12 l/min 14 l/min
DHW flow rates 35°C ................................... 10,3 l/min 12 l/min
Cold water mains pressures Min operating... 0,5 bar 0,5 bar
Cold water mains pressures Max operating.. 10 bar 10 bar
Flow limiter rate............................................. 8 l/min 10 l/min
Safety discharge ........................................... 3 bar 3 bar
Expansion vessel - Pre-charge pressure ...... 0,7 bar 0,7 bar
Net capacity at 3 bar in liter........................... 5,44 5,44
Supply ........................................................... 230 v 230 v
Consumption ................................................. 150 w 150 w
Protection ...................................................... IP 44 IP 44
Fuse F1/F2/F3/F4 ......................................... 2 A/1,25 A/0,315 A/0,250 A
External controls ........................................... 24 v 24 v
Natural gas G20
Gas rate C/H max ................... 2,64 m3/h 3,01 m3/h
Gas rate DHW max ................. 2,64 m3/h 3,01 m3/h
Gas rate C/H & DHW mini....... 0,87 m3/h 1 m3/h
Gas valve restrictor diameter .. without without
Propane L.P.G G31
Gas rate C/H max. .................. 1,94 kg/h 2,21 kg/h
Gas rate DHW max. ................ 1,94 kg/h 2,21 kg/h
Gas rate C/H & DHW mini....... 0,64 kg/h 0,73 kg/h
Gas valve restrictor diameter .. 4,40 mm 4,8 mm
24 kW : 380
30 kW : 405
24 kW 30 kW 24 kW 30 kW

2
Pump and expansion vessel characteristics
Components location
Note : The system initial pressure should be over the following value :
System static height (in metre) + 0.7 = Initial pressure (in bar)
10
GV F= high speed by-pass closed
GVO = high speed by-pass open
PV F= low speed by-pass closed
PVO = low speed by-pass open
20 40 60 80 100 120
Pf
140 160 180 200 220 240
0,7
0,8
0,9
1,0
1,1
1,2
1,3
1,4
1,5
1,6
1,7
1,8
1,9
2,0
Capacité maximale de l'installation (en litres)
80°C
70°C
60°C
50°C
40°C
260
Pression à froid pour le circuit chauffage (en bar)
Cliter
System capacity chart
Central heating initial pressure when cold (in bar)
0
4
3
2
1
5
6
100 200 800
700
600
500
400
300 900 10001100 l/h
mCE Débit mini (robinets thermostatiques fermés)
Hauteur manométrique
GVF
GVO
PVF
PVO
Pump head available
Minimum flow rate (with all heating thermostatic valves closed)
bar
0
13
4
1
2
3
4
5
6
8
11
12
13
14
7
15
10
9
16
1.- Steel chassis complete with expansion vessel (not visible)
2.- Sealed chamber
3.- Burner and heat exchanger assembly
4.- Air / gas connection
5.- 24 V modulating fan
6.- Gas valve
7.- Ignition electrode
8.- Ionisation probe
9.- Ignitor
10.- Combustion products manifold
11.- 24 V transformer
12.- Siphon
13.- Electrical box
14.- Pump
15.- Secondary heat exchanger
16.- Pressure gauge
17.- Three way valve
18.- Automatic air separator and automatic vent
19 - Central heating flowswitch
20.- Domestic hot water flowswitch
21.- Central heating control thermistor
22.- Hot water control thermistor
23.- Overheat sensor
37.- Central heating flow isolating valve
38.- Domestic Hot Water outlet
39.- Gas service tap
40.- Water service tap
41.- Central heating return isolating valve
42 - Silencer
43.- Central heating pressure relief valve
46.- User’s guide
47.- Connecting tails (x5)
48.- Condensate drain
49.- Adjustable by-pass
50.- Right hydraulic assy
51.- Left hydraulic assy
23
20
21
17
19
18
22
23
39 40 41
38
37 43
46
47
48
49
50
51
42

3
FUNCTIONING
Control panel
35
30 242627
25
34
28
33 36
31 3229
24.- Display
25.- Domestic Hot water switch
26.- Green indicator – Domestic Hot Water mode ON
27.- D.H.W. temperature reducing key
28.- D.H.W. temperature increasing key DHW mode indicator
29.- Central Heating switch
30.- Green indicator – Central Heating mode ON
31.- Central Heating temperature reducing key
32.- Central Heating temperature increasing key
33.- Green indicator – Power ON
34.- Orange indicator - Burner ON
35.- Red indicator - Lock out / flame failure
36.- Reset key
Switching on
1. Check that pressure in central heating system is above 0.7 bar and below 1.5 bar with the pressure gauge 16.
2. Check that the gas service tap is opened at the gasmeter and main power is on. Green indicator Power ON
33.
3. Open the gas tap 39.
The boiler is now ready to use.
Attention ! If the boiler stays a long time without working, some air in the gas pipe can hinder the first lightings. (please refer to
paragraph 18 Incorrect Function)
Switching on Central heating
Press on key 29 , the green indicator 30 will light and the display will show the Heating
flow temperature.
Keys 31 and 32 allow to adjust the temperature required in the Central Heating system
regarding the weather conditions.
• press to increase temperature when weather is cold
• press to reduce temperature when weather is fair
During the temperature setting operation the display will flash.
If the room thermostat is calling for heat, a dot will be displayed at the bottom of the 3rd digit
Switching on the Domestic Hot water
Press on key 25 , the green indicator 26 will light :
If there is no water demand
the display will show the following graphic
In case of draw off
a square made of 4 digits will move clockwise on the display
Keys 27 and 28 allow to adjust the temperature required for the Domestic Hot Water flow. During the temperature set-
ting operation the display will flash.
Note : The configuration of CH system can generate some gravity effect when the boiler is set in DHW mode only. It may result a
temperature rise of the heating pipes close to the boiler (or eventually a radiator). To avoid that, it is possible to close during sum-
mer period (Central Heating switched off) the heating flow isolating tap (37). Don’t forget to open it when you will switch on the
Central Heating mode again.

4
Switching on the Domestic Hot water and Central Heatingh together
Press on key 29the green indicator 30will light.
Press on key 25the green indicator 26will light.
If there is no water demand the display will show the heating flow temperature
In case of draw off asquare made of 4 digits will move clockwise on the display
Turn off the boiler
- Press on key 29 and 25 , to switch off both DHW and CH mode. The green indicators 30 and 26 will stop
- Switch off the main electrical supply
- Shut off the gas service tap 39
Note : In this conditions, the anti-freeze system is inoperative
Stand by mode A fixed digit at the centre of the display and the green indicator 33 on
Putting the boiler in stand by mode and anti freeze system. :
Press on key 29 and 25 , to switch off both DHW and CH mode. The green indicators 30 and 26 will stop.
During the all duration of the stand by mode, an automatic anti-sticking system will switch on the pump for 1
minute and make a movement of the 3 way valve each 23 hours.
The stand by mode will disable the anti-freeze function of the room thermostat (if fitted). To leave the room thermo-
stat anti freeze system operative, please let the Central Heating mode on.
The boiler is equipped with an automatic anti freeze system which permanently on.
If the Central Heating temperature decrease bellow 7°C, the pump will start.
If the Central Heating temperature decrease bellow 4°C, the pump and the burner will start.
Domestic Hot Water Mode
To be able to supply hot water, the DHW
mode should be ON. Press on key 25
, the green indicator 26 will light.
If there is no water demand, the display
will show the following graphic
In case of draw off, a square made of 4
digits will move clockwise on the display
.
Keys 27 and 28 allow to adjust
the temperature required for DHW, flow.
During the temperature setting opera-
tion, the display will flash.
When a tap or a shower is turned on, the
flow of mains water, above 2 litres per
min., will activate the DHW flow switch
20 and allow the 3 way valve 17 to move
to the DHW position. The pump can now
circulate primary water heated by the
main exchanger through the secondary
heat exchanger. The primary flow switch
controls that this flow rate is over
4lt./min. to allow the lighting sequence to
begin.
The fan on the gas valve assembly starts
and when the lighting speed is reached
(detected by a hall effect sensor) the 2
safety solenoids open together to allow
gas to the burner. The ignition sequence
begins and a continuous high speed
spark ignites the gas. As soon as a flame
is detected, the orange indicator led 34
will light and the regulation system will
be able to adjust the gas rate regarding
the heat load. If a flame is not detected,
after 10 seconds, the security solenoids
close together and shut off the gas. The
red lockout indicator led 35 will light.
Press the reset button to re-light the
burner.
The domestic hot water temperature is
controlled by the hot water control ther-
mistor 22 and the central heating control
thermistor 21. This system anticipates
the changes of temperature in the sec-
ondary heat exchanger and ensures
accurate temperature regulation.
When the tap is closed, the burner is
extinguished and the pump stops. The
boiler will now stay in the hot water mode
for 3 minutes to maintain temperature to
ensure a fast response in the event of a
subsequent hot water demand.
Priority will be given to a demand for hot
water. This will interrupt the central heat-
ing for the duration of hot water delivery.
Central Heating Mode
To be able to supply heating, the mode
should be switched ON. Press on key 29
, the green indicator 30 will light, and
the display will show the Heating Flow
temperature.
Keys 31 and 32 allow to adjust
the temperature required for Central
Heating system regarding the weather
conditions. During the setting operation,
the display will flash.
When there is a demand for heating,
(either from the room thermostat or the
clock) the pump starts. If the boiler tem-
perature control is calling for heat and
the primary flow rate over 4 lt./min., the
central heating flow switch operates,
allowing the ignition sequence to begin.
The fan on the gas valve assembly starts
and when the lighting speed is reached
(detected by a hall effect sensor) the 2
safety solenoids open together to allow
gas to the burner. The ignition sequence
begins and a continuous high speed
spark ignites the gas. As soon as a flame
is detected, the orange indicator led 34
will light and the regulation system will
be able to adjust the gas rate regarding
the heat load. If a flame is not detected,
after 10 seconds, the security solenoids
close together and shut off the gas. The
red lockout indicator led 35 will light.
Press the reset button to re-light the
burner.
The central heating flow temperature is
controlled by the central heating control
thermistor 21. The boiler has been
designed to minimise cycling and will not
attempt to re-light for at least 3 min. after
the boiler thermostat has been satisfied.
When the room thermostat is satisfied ,
the burner will switch off and the pump
will remain running for a further 3 min-
utes before it too stops.
Note
It is possible to override the 3 minute
delay by pressing the Reset key 36.

5
Lockout procedure
Flame disappearance :
When the ionisation electrode 8does not
detect flame presence. The orange indi-
cator led 34 extinguishes. A lighting
cycle starts. If a flame is not detected,
before 10 seconds, the safety solenoids
will close. The lockout red indicator 35
lights and the display shows the error
code. The pump runs and the 3 way
valve 17 stays in its position. After a few
seconds, it will become possible to reset
the boiler by pressing the reset key 36.
Overheat detection :
If an overheat (over 100°C) is detected in
the primary circuit by the sensor 23, the
safety solenoids close and the fan stops.
The orange led 34extinguishes and the
pump remains running for 3 minutes.
The reset will be possible when the pri-
mary temperature will decrease under
76°C.
CENTORA GREEN FUNCTIONAL DIAGRAM
Heating mode Hot water mode
40
49
48
43
41
20
39
38
37
22 19
21
23
18
17
16
14
13
12
6
3
8
15
5
7
DIAGRAM
ELECTRICAL WIRING

6
5 ” Menu - 1 - Default register
Record the last 10 defaults
Section Digit 1 Digit 2 and 3
Last default occured 0•code from 01 to 99
Last but one default occurred 1•code from 01 to 99
... ... code from 01 to 99
Last default occurred before the previous one 9•code from 01 to 99
Menu - 2 - Boiler conditions
Indicates the conditions or the configurations of the boiler
Section Digit 1 Digit 2 and 3
Software version of display PCB 0•10 to 99
Flue type 2•1: FF
variable speed
Room thermostat is calling for heat 3•0: no
3•1: yes
Theoretical position of the 3 way valve 4•0: DHW
4•1: CH
DHW flow temperature in Celsius degrees 5•from 00 to 99
CH flow temperature in Celsius degrees 7•from 00 to 99
Software version of main PCB 9•10 to 99
DISPLAY
ACTION CONFIGURATION
once
x times
x times
Note -- is displayed if no default is recorded.

7
Menu - 3 - Boiler options
DISPLAY
ACTION CONFIGURATION
Section Digit Digit
1 2 and 3
Under floor heating system 0 0: no
1: yes
Celectic 4 0: no
1: yes
DHW Delay 5 0to 5 mn by step 0.5mn
(time before CH relight after a DHW cycle)
DHW flow swith Delay 6 0 to 20 1/10 seconde
(time before DHW flow detection to
override pressure peak problem)
Factory
setting
once
x times
Menu - 4 - Boiler settings
Section Digit Digit
1 2 and 3
Room thermostat operation 0 0: Burner only
01: Burner and pump
Pump speed 1 0: High speed
11: Low speed
Pump post circulation duration 2 0,0 min
From 0 to 5 minutes by step of 0.5 min. 2 0,5 min
21,0 min
25,0 min
Maximum Central Heating flow temperature 4 50°C
480°C
CH anti cycling delay 8 0,0 min
From 0 to 7 minutes by step of 0.5 min. 8 0,5 min
82,5 min
85,0 min
CH maximum output limitation
Model 24
From step 0 (P. min.) 8 kW Value from
to step 10 (P. max.) 24 kW 9 0 to 10
Model 30
From step 0 (P. min.) 9 kW 9 Value from
to step 10 (P. max.) 28 kW 0 to 10
Factory
setting
DISPLAY
ACTION CONFIGURATION
once
x times

8
Menu - 5 - Combustion rate control mode
X X
DISPLAY
ACTION CONFIGURATION
wait 5 ” Combustion rate control mode OFF
Switching on the combustion rate
control mode. Central heating output
reach the maximum power set in
menu 4 section 9.
Central heating temperature is dis-
played in celsius degrees.
The 3 dots indicate that the combus-
tion rate control is ON at maximum
output.
Switching the combustion rate
down to minimum power.
Central heating temperature is dis-
played in celsius degrees.
The dot indicates that the combus-
tion rate control is ON at minimum
output.
Switching on the combustion rate to
maximum output set in menu 4 sec-
tion 9.
Central heating temperature is dis-
played in celsius degrees.
The 3 dots indicate that the combus-
tion rate control is ON at maximum
output.
X X
Switching off the combustion rate
control mode.
press once
press once
press once
press once
press once
Effect Display
Locking conditions of the combustion rate control mode :
- boiler in stand by mode
- D.H.W. draw off
- room thermostat is not calling for heat
- room thermostat is calling for heat but the maximum temperature is reached
- boiler in lockout mode
- after a reset or if the main supply fails
- end of the mode if operator leave menu 5
- after 15 minutes if there is no actions on keyboard
Nota : As soon as the combustion rate control mode is on, Central Heating and Domestic Hot Water keys
are inactive.

9
CH heat output setting :
If you would like to change the setting of C/H heat output to 12 kW, please proceed as follow :
(note : the factory setting is 18 kW and the following explanation refer to menu 4 section 9)
- Switch to installer mode, press key
and on DHW side for 5 sec-
onds.
The display shows :
-1- then 0•-- if there is no default in the
default register.
- press 3 times on menu key (on
CH side ) to gain access to menu -4-,
The display shows :
-4- then the value set for section 0 ( 00
or 01 respectively Action on burner only
or pump and burner)
- change for section 9 (Adjustment of
CH heat output). Press on key on
DHW side times.
The display shows :
(906 (which corresponds to the 18 kW
which is the factory setting)
9= section 9 06 = 18 kW
- press on setting key (on CH
side)one time, the 2nd and 3rd digits
flash together. Then press on or
key on DHW side to
change the C/H heat output step
between 00 and 10.
Press on setting key to confirm the
value. The display stops flashing.
Setting procedure is finished.
To exit from setting mode, leave the
boiler for approx. 1 minute then the
computer will switch back to user mode.
After programming please close the
door P(fig. 18)
1
Display
2x 3
1
2
or
33x 9
44
5 ”

10
REGULATION FLOW SWITCHES
Temperature regulation for both C/H and DHW circuits are controlled by 2
thermistors. The C/H knob allows the adjustment of temperature between 35
and 85°C. The DHW temperature is limited to 60°C. DHW and C/H thermis-
tors are identical and interchangeable.
Resistance value are
- 5000 Ωat 25 °C
-2631 Ωat 40°C
- 620 Ωat 80°C
- 255 Ωat 110°C
Flow in both D.H.W. and Heating cir-
cuits are detected by 2 flow switches. A
piston with a magnet at the top operates
aREED switch. The piston is lifted by
flow rates listed below :
Flow rate threshold :
D.H.W. 120 l/h ±20 l/h
C/H 250 l/h ±20 l/h
ROUTINE SERVICING
To ensure continued efficient operation of the appliance, it is recommended that it is checked and serviced as necessary at reg-
ulars intervals. The frequency of servicing will depend upon the particular installation condition and usage, but in general, once
a year should be adequate.
It is the law that any service work must be carried out by a competent person such as your local Chaffoteaux Service Centre,
British Gas or other CORGI registered personnel in accordance with the current Gas Safety (Installation and Use) regulation.
Attention ! the air/gas connection pipe between the gas valve and the burner should never open. The seal can be checked only
in the factory.
The service schedule should include the following operations :
- Check the pressure in the system
- Check the correct operation of the appliance
- Check the correct operation of the gas controls
- Check the functions of safety controls
- Clean the electronic board of the fan located on the gas valve assembly and the different transformers in the sealed chamber.
- Check combustion chamber insulation panels for damage
- Check the lighting and ionisation electrodes condition
- Clean the burner (Never use metallic brush which can damage the stainless steel)
- Clean the heat exchanger (Never use metallic brush which can damage the stainless steel)
- Clean the siphon and pay attention to the acidity of its contents
- Check the correct seal of the drain system
- Clean gas and water filters
- Check expansion vessel charge pressure
- Clean an check operation of safety valve
- Check the correct seal of the flue system.
Additional procedures that may be necessary :
- Check the burner pressure and the gas flow rates
- Check, clean or replace components as necessary
- Carry out combustion test utilising the test points in the flue turret
Suggested sequence for servicing :
Before disconnecting or removing any part, isolate the gas and electricity supplies. Ensure that the appliance is cool, and take
care about the condensats products content in the siphon which are acid.
(For detail, please see section on Parts Removal and Replacement)
Preliminary checks
- Remove outer case
- Check the system pressure is at least 0.7 bar cold
- Check the modulation of the gas valve in DHW mode by reducing progressively the flow rate at a tap.
- Check that the burner is extinguished fully when both solenoids are closed and fan is off.
- Test ionisation functions and check that lockout occurs by turning off gas tap.
- Whilst boiler is operating, check operation of the primary flow switch by closing heating flow valve and by pass screw (turn
clockwise ) noting the number of turns so that it may be reset correctly.
- Control the correct flood of condensats in the siphon which is transparent.

11
REMOVAL AND REPLACEMENT OF PARTS
Before removing appliance case, isolate
the gas and electrical supplies. Isolate
boiler from the system and drain before
removing any component in the water-
ways. Ensure that the appliance is cool.
1. Outer Case
Remove four screws in base of case and
lift free. When replacing, carefully locate
on lugs Ton top edge of chassis.
2. Sealed chamber front panel
Unscrew four self taping screws secur-
ing the sealed chamber front panel and
lift over top corner locating lugs.
Reassemble in reverse order.
3. Combustion Chamber front panel
and air/gas connection
Carry out step 1 and 2 as above.
Unscrew three screws securing the
air/gas connection pipe onto the gas
valve assembly. Disconnect Ionisation
and lighting electrodes from their wiring.
Unscrew six nuts to release combustion
chamber front panel and pull the assem-
bly towards you. Reassemble in reverse
order.
4. Ionisation electrode
Carry out step 1 and 2 as above.
Disconnect ionisation electrode from its
wiring. Loosen the 2 screws and pull it
out from the combustion chamber front
panel. Replace the ionisation gasket
provided. Reassemble in reverse order.
5. Lighting electrode
Carry out step 1 and 2 as above.
Disconnect lighting electrode from its
wiring. Loosen the 2 screws and pull it
out from the combustion chamber front
panel. Replace the ionisation gasket
provided. Reassemble in reverse order.
6. Burner
Carry out step 1, 2 and 3 as above.
Remove the 4 Philips screw retaining the
burner onto the combustion chamber.
Pull it out with care to avoid any damage
to the ceramic panel protecting the com-
bustion chamber front panel. Replace
the burner gasket. Reassemble in
reverse order.
7. Gas vale assembly
Carry out step 1 and 2 as above.
Unscrew three screws securing the
air/gas connection pipe onto the gas
valve assembly. Disconnect the connec-
tors from gas solenoids and fan. Loosen
the gas pipe nut. Unscrew six nuts to
release combustion chamber front panel
and pull the assembly towards you.
Replace gas filter before fitting the full
assembly back in the boiler.
8. Fan assembly
Carry out all operations mentioned in
step 7. Unscrew the three screws secur-
ing the air/gas connection pipe onto the
gas valve assembly. Separate the gas
valve assembly and the venturi from the
fan assembly by loosen the two hexago-
nal head screws. Reassemble in reverse
order and replace the necessary gas-
kets.
9. Gas section
Carry out all operations mentioned in
step 7. Unscrew the three screws secur-
ing the air/gas connection pipe onto the
gas valve assembly. Separate the gas
valve assembly and the venturi from the
fan assembly by loosen the two hexago-
nal head screws. The venturi and the
gas section can be separated loosing
the 2 screw located at the top of the gas
valve. Replace necessary gaskets
before reassemble in reverse order.
10. Venturi in the gas section
Carry out all operations mentioned in
step 7. Unscrew the three screws secur-
ing the air/gas connection pipe onto the
gas valve assembly. Separate the gas
valve assembly and the venturi from the
fan assembly by loosen the two hexago-
nal head screws. The venturi and the
gas section can be separated loosing
the 2 screw located at the top of the gas
valve. Replace necessary gaskets
before reassemble in reverse order.
11. Drain down
3 drain points are located on the boiler.
1= DHW circuit drain point
2 = Heating circuit drain point
12. Water filters ( DHW and Heating)
The DHW filter ensures a seal between
the connecting bracket and the pipe to
the DHW flow switch. Drain the boiler as
in step 12. Unscrew the pipe nut and
remove the clip on the hydraulic assy.
Pull the pipe toward you and remove the
water filter from its location.
The C/H filter is located in the right
hydraulic assembly. Remove the return
pipe as described previously and with-
draw the filter. Reassemble in reverse
order.
13. Flow switches
Drain boiler as in step 12. Disconnect
the electrical plug, turn the top cover
anti-clockwise, remove the O-ring and
the brass piston. Reassemble in reverse
order.
14. 3-Way valve
Drain boiler as in step 12. Remove the 3
clips on the 3 way valve. Remove the
clip on the exchanger flow pipe. Pull the
pipe down then pull it out of the 3 way
valve. Disconnect the plug from the
motor. Unscrew the nut on the pipe
between the connecting bracket and the
3 way valve and pull it toward you.
Rotate the 3 way valve body anti-clock-
wise to unclip it from the left hydraulic
assembly.
15. Secondary heat exchanger
Drain both circuits of the boiler as in step
12. Unscrew the 2 fixing screws Dand
remove the DHW exchanger from the
front. Prior to reassembly, check that the
4 gaskets are correctly positioned. The
heat exchanger is so designed that it
cannot be remounted incorrectly.
AAAA
TT
1
2
12
air separator
D

12
16. Main heat exchanger
Carry out step 1 and 2 as above. Drain
down the boiler as in step 12. Unscrew
three screws securing the air/gas con-
nection pipe onto the gas valve assem-
bly. Disconnect Ionisation and lighting
electrodes from their wiring. Unscrew six
nuts to release combustion chamber
front panel and pull the assembly
towards you. Undo the two clips of the
pipes to the main exchanger and pull
down the pipes. Unscrew the three
screws located at the bottom, top left
and at the right with the retaining system
to be able to pull the main heat exchang-
er towards you.
Reassemble in reverse order taking care
about the location of the gasket on the
fumes collector and replace the neces-
sary gaskets.
17. Pump
Drain boiler as in step 12. Pivot the elec-
tical box downwards. Open the electrical
box cover removing the 2 screws.
Remove the pump plug from the power
board and earth plug from earth socket.
Unscrew the nut Fof the return pipe
from the volute. Remove the clip Gon
the pump volute and pull the pump
toward you. Reassemble in reverse
order.
18. Pressure relief valve
The pressure relief valve can be ser-
viced from the front of the appliance.
Drain the boiler first, undo the retaining
screw and pull out the
valve.Reassemble in reverse order.
19. Thermistors
Drain the boiler as step 12. Disconnect
the plug, remove the retaining clip pull
the thermistor out. Reassemble in
reverse order.
22 = DHW thermistor
21=Heating thermistor
20. Safety thermostat
Remove the casing as step 1 and hinge
down the electrical box as step 5.
Disconnect the 2 cables, pull out the
sensor with the clip (13). Reassemble in
reverse order.
21. Spark generator
Carry out step 1 and 2 as above. Unplug
the connector from the spark generator
located on the right hand side of the
main heat exchanger. Loosen the two
screws to remove the igniter.
Reassemble in reverse order.
22. Main control board
Carry out step 1 as above and hinge
down electrical box by pressing the
retaining tabs Pon either sides. Remove
wiring cover C. Undo the 4 screws of the
electrical rear panel and remove it.
Unplug all cables from the PCB, remove
earth plug from earth socket. Hang out
the main PCB. Reassemble in reverse
order.
23. Display PCB
Carry out step 1 as above and hinge
down electrical box by pressing the
retaining tabs P on either sides. Remove
the pressure gauge clip. Rotate the elec-
trical box back in upper position. Undo
the 2 screws retaining the front panel,
put your two hands at the bottom of the
front panel and pull it down to release it
from the 2 clips. Hinge down again the
electrical box. Undo the 4 screws of the
electrical rear panel and remove it.
Unplug the display board cables from
the main PCB. Reassemble in reverse
order.
24. Expansion vessel
Remove the casing as step 1 and drain
the boiler as step 12 above. Unscrew the
connecting tails nuts and lift out the boil-
er from the wall. Place it on a side on the
floor. Remove the expansion vessel
bracket retaining screws, disconnect the
pipe from the vessel and pull it toward
you. Reassemble in reverse order.
25. pressure gauge
Carry out step 1 as above and drain the
boiler as step 12. Hinge down electrical
box by pressing the retaining tabs P on
either sides. Press on the clip to remove
it and pull it out. Remove the clip which
hold the connection of the capillary on
the pump hose. Hang out the pressure
gauge with its capillary. Reassemble in
reverse order.
26. condensate trap
Carry out steps 1 and 2 as above.
Remove the clip (R). Remove the sili-
cone tube (S) between the condensate
trap and the burner.
Remove the PVC tube (T) using for the
evacuation of condensation.
Reassemble in reverse order taking
care the new condensate trap is
filled with water before putting it into
the boiler.
F
G
21
22
23
P
P
C
R
S
T

13
FAULT FINDING CHART Part 1
Switch on the main electrical supply
Does the green LED
alight ?
- Check mains electrical
connection
- Check internal fuses
- Check connection between
the 2 PCBs
Replace control PCB or
display PCB
Replace control PCB
Replace DHW flow switch
Switch Domestic Hot Water
mode ON
Release pump rotor
Replace pump
Replace fan assembly
Replace heating flow switch
Does the red LED
light ?
Does the display
show a - XX code ?
Does the fan run ?
Check heating flow switch
Check voltage on
the fan
Check the 24 V at
the transformer
Press the reset button
Please refer to the list of error
codes and solve the problem
Does the pump run ?
Check that the
pump spins freely
Check voltage in the
pump electrical box
Replace control PCB
Could you see the
spark generation?
Does the spark
generator energize ?
Does the -24 error
display ?
Replace spark generator or
ignition electrods assembly
Replace transformer or the rel-
evant fuse
- Check pressure probes
or
- Check flue duct condition
or
- Replace pressure switch
Yes
Yes
Yes
Yes
No
No
No
No
Ok
Ok
No
Check or replace main or sec-
ondary heat exchangers. They
could be fully scaled.
Check flow in the
boiler primary circuit
Ok
No
Replace heating thermistor Check heating
thermistor
Ok
No
No
No
No
Yes
Yes
Yes
No
No
No
Ok
Ok
Ok
Ok
means a test or a choice
means an action
means a group of actions
error code displayed
PLEASE CHECK THE FOLLOWING POINTS CAREFULLY
BEFORE GOING THROUGH THE FAULT FINDING CHART
-Gas pressure -Electric mains
-Minimum water pressure in the heating circuit (over 0.8 bar) -All isolating valves have been opened
-Boiler air vented
-Minimum domestic hot water flow of 2 l/min -Check that the heating filter is clear.
- Remove the front panel of the sealed chamber
-7
Yes
Check or replace the DHW fow
switch
Draw off Domestic Hot Water
at a tap
Does the pump run ?
No
Check DHW flow
switch operation
No No
Ok
-7
-7
-11
-12
Ok
Ok
No
No
-3
Wait for 4 seconds
-3
Error code Description
1Overheating LockOut
3No flame detection
5Anti-frost mode on
6Anti-frost mode on
7No water circulation
8Faulty water circulation in the primary circuit
9DHW thermistor faulty, Opened circuit
10 DHW thermistor faulty, Short circuit
11 Central heating thermistor faulty, Opened circuit
12 Central heating thermistor faulty, Short circuit
18 Ignition test
20 Faulty connexion
23 Low speed fan
24 Faulty control functionning fan
29 3 ways valve locked in Heating position
31 Error communication with EEPROM
32 Error communication with the main PCB

14
FAULT FINDING CHART Part 2
Replace control PCB
Can you see the
flame on the burner ?
Replace gas section assembly
Do you feel air
drawing in at the air inlet ?
Do the gas
solenoïds energise ?
Check that air inlet pipe, ven-
turi, fan, air/gas pipe or burner
are free of dust and not blocked
Purge the gas pipe and press
on reset button
Does the DHW tem-
perature rise?
Does the burner still
alight ?
Does the red LED
light and -3 displayed ?
Does the orange
LED light ?
Replace control PCB
Replace DHW thermistor
Replace control PCB
Replace display PCB or control the
connection between the 2 PCBs
- Adjust the DHW flow rate to
3 l/min at a tap.
- Wait until the temperature
becomes stable.
No
No
No
No
No
Yes
No No
Does the orange
LED light ?
No
Yes
Replace the DHW heat
exchanger
Yes
Yes
Yes
Yes
No
-3
Replace display PCB or control the
connection between the 2 PCBs
Is the combution
chamber full of conden-
sates ?
Yes
Check ionisation
probe
No
Ok
Drain and clean combustion cham-
ber, siphon and drain pipes
Yes
Replace the ionisation probe
No
Stop water draw off
Does DHW temper-
ature rise over 70°C ?
Check DHW ther-
mistor
No
Ok
- Press on DHW key to switch
off DHW mode.
- Press on CH key to switch on
CH mode and set CH tempera-
ture to maximum.
- Press the RESET button to
cancel the 3 min. delay.
- Ensure that external controls
are calling for heat.
Does the heating
outlet pipe temperature rise
?
Wait until the return pipe
become hot then reduce CH
temperature to minimum
Does the orange
LED light ?
Replace the 3 way valve
Replace control PCB
No
Yes
The boiler is OK
No
Does the heating
outlet pipe temperature
rise ?
Replace the 3 way valve
Yes
-29
No Yes
Yes
Yes

15
SHORT LIST
101 BURNER 61306074 .
BURNER 61309327 .
102 DOOR ASSY 61308492 .
DOOR ASSY 61308491 .
110 ELECTRODE KIT 61309624 ..
401 GAS SECTION ASSY 61312986 B/P .
GAS SECTION ASSY 61312987 B/P .
GAS SECTION ASSY 61307584 NAT .
GAS SECTION ASSY 61310129 NAT .
407 FAN ASSY 61307585 ..
505 THREE-WAY VALVE 277833 61010000 ..
507 OVERHEAT THERMOSTAT 100°C 277783 61010572 ..
510 THERMISTOR TEMP. SENSOR 277834 61000733 ..
514 WATER/WATER HEAT EXCHANGER E00612 61011164 ..
532 WATER THROTTLE 277846 60081471 ..
560 AIR SEPARATOR HEAD ASSEMBLY 277857 61002653 ..
572 PUMPE UP 15/50 230V E11662 61010612 ..
607 IGNITER 379075 61002105.20 ..
615 PRINTED CIRCUIT BOARD 61310357 ..
627 FUSE 250V 2A - TEMPORIZED 277883 61003456 ..
628 FUSE 250V 1A - TEMPORIZED 61003634 ..
629 FUSE 250V 1,25A - TEMPORIZED 277884 61003635 ..
630 FUSE 250V 0,315A - TEMPORIZED 61307845 ..
640 TRANSFORMER 61307647 ..
805 PRESSURE GAUGE 61303158 ..
938 PRESSURE RELIEF VALVE 61020933 ..
DescriptionKey N°
Manf. Pt. N°
Type G.C N°
FF
Manf. date
CENTORA GREEN 24
from to
110
407
401 532
572
505
640
514
510
507
R41
R37
R31
R30
R29
J7
C38
R102
1
+
+
+
++
+
+
+
8
C68
R28
ST2
FT1A
C19
Z11A
Z10A
Z9A
Z8A
R135
DL1
TH1A
Z7A
Z6A
R132
U5
Z5A
Z4A
TERRE-1
TH1
R48
R27
R91
R89
R47
C83
C78
C80
C79
ST1
R87
Z10
Z9
Z6
Z7
Z5
Z4
Z3
Z2
Z11
Z1
U3
U10
U9
U7
U6
U4
TR1
TH2
TERRE
T8
T7
T5
T4
T3
R46
T2
T6A
T6
T12
T11
T10
T1
SW1
RL8
RL7A
RL7
RL6
RL10
RL5A RL5
RL4A RL4
RL3A
RL3
RL2A
RL1A
RL9
RL1
RAD1
R118
R114
R113
R111
R112
R110R109
R108
R107 R106
R9
R105
R101
R100
R99
R98
R97
R96
R8
R95
R94 R93
R92
R90 R88
R66
R65R64
R62
R7
R58
R59
R57
R24
R52
R53
R51
R6
R50
R49
R55
R5
R22
R79
R78
R77
R45
R43
R44
R42
R4
R39
R38
R35
R34
R3
R33 R32
R19
R18
R2
R16
R20
R21
R15
R14
R26
R25
R23
R13
R131
R130
C82
C81
T14
T13
D45
D44
RL12
R76
R12
R75
R74
R73
R72
R71
R70
R69
R68
R67
R129
R11
R128
R127
R116
R115
R122
R121
R120
R119
R117
R10
R1
Q1
P2
P1
MOV1
L1
J9
J10A
J8
J6
J4
J3
J2
J1FT1
F3A
F3
F2A F2
F1A
D9
D7
D6
D5
D34
D31
D30
D32
D4
D42
D41
D40
D39
D38
D37
D36A
D36
D33
D43
D3
D29
D28
D27
D26
D23
D25
D24
D22
D21
D20
D2
D19
D18
D17
D16
D15
D14
D13
D12
D11
D1
CTP1
C8
C13
C49
R54
RL11
C34
C35
C32
C7
J5
C53
C6
C52
C51
C77
C76
C75
C74
C72
C71
C70
C69
C5
C50
C48
C47 C46
C45
C44
C43
C42
C67
C4
C66
C65
C64
C63
C62
C61
C60
C59
C22
C56
C55
C54
C33
C31
C41
C39
C37
C2
C36
C29
C30
C28
C27
C26
C25
C10
C11
C9
C3
C24
C23
C21
C20
C18
C17
C16
C15
C14
C12
C1
K
VD
M/A
VITESSE
K
1
1
1
1
1
EXT
1
P4
P3
P2
P1
BUS
1
PROGTA
K
K
KCD
1
K
K
230V
+5V
TR
COM
REP
8
1234
0

N
628
627
629
630
607
805
560
CENTORA GREEN 30
615
102 101
938

1309456d - 06/2004
Chaffoteaux & Maury are continuously improving their products and therefore reserve the right to change specifications without prior
notice and accepts no liability for any errors or omission in the information contained in this document.
Manufacturer: Chaffoteaux & Maury - France
Commercial subsidiary: MTS (GB) Limited
MTS Building
Hughenden Avenue
High Wycombe
Bucks HP13 5FT
Telephone: [phone]
Fax: [phone]
Internet: www.chaffoteaux.co.uk
E-mail: [email protected]
Technical Support Help Line: 0870 241 8180
Customer Service Help Desk: 0870 600 9888
This appliance is suitable for Natural gas or LPG. A gas conversion must be made by a competent person.