Italtherm CITY CLASS 20 F User manual

CITY CLASS
Manual
SERVICE
ENG
20 F - 25 F - 30 F - 35 F
20 FR - 25 FR - 30 FR - 35 FR
Green Heating Technology

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SERVICE Manual City Class F-FR
Table of Content
Available models � � � � � � � � � � � � � � � � � � � � � � � � � � 2
PCB code � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3
PCB boiler combustion reset � � � � � � � � � � � � � � � � � � 4
Check list first ignition � � � � � � � � � � � � � � � � � � � � � � � 5
User guide
Access to the inside of the boiler � � � � � � � � � � � � � 7
Boiler internal components 20-25-30F � � � � � � � � � 8
Boiler internal components 20-25-30FR � � � � � � � � 9
Boiler internal components 35F � � � � � � � � � � � � � 10
Boiler internal components 35FR � � � � � � � � � � � � 11
Hydraulic diagram F � � � � � � � � � � � � � � � � � � � � � � 12
Hydraulic diagram FR � � � � � � � � � � � � � � � � � � � � � 13
Electrical diagram F � � � � � � � � � � � � � � � � � � � � � � 14
Electrical diagram FR � � � � � � � � � � � � � � � � � � � � � 15
Heating system filling and pressuring � � � � � � � � � � 16
Dismounting and mounting
DHW exchanger � � � � � � � � � � � � � � � � � � � � � � � � 19
Combustion components � � � � � � � � � � � � � � � � � 20
Gas valve calibration � � � � � � � � � � � � � � � � � � � � � 22
How to access the parameters � � � � � � � � � � � � � � 23
Parameters F-FR � � � � � � � � � � � � � � � � � � � � � � � � � 24
Info menù � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 26
Error history � � � � � � � � � � � � � � � � � � � � � � � � � � � � 27
Errors F-FR � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 25
Service function � � � � � � � � � � � � � � � � � � � � � � � � � 29
Pump diagram F � � � � � � � � � � � � � � � � � � � � � � � � � � 26
Pump diagram FR � � � � � � � � � � � � � � � � � � � � � � � � � 27
Technical Data
Technical boiler data F � � � � � � � � � � � � � � � � � � � � � 28
Technical boiler data FR � � � � � � � � � � � � � � � � � � � � 34
Available models
Model GAS type* PCB configuration
code
City Class 20 F Max heat input 20 kW G20
(G30/G31)
20120
(21120)
City Class 25 F Max heat input 25 kW G20
(G30/G31)
20120
(21120)
City Class 30 F Max heat input 30 kW G20
(G30/G31)
20120
(21120)
City Class 35 F Max heat input 35 kW G20
(G30/G31)
20120
(21120)
City Class 20 FR Max heat input 20 kW G20
(G30/G31)
20130
(21130)
City Class 25 FR Max heat input 25 kW G20
(G30/G31)
20130
(21130)
City Class 30 FR Max heat input 30 kW G20
(G30/G31)
20130
(21130)
City Class 35 FR Max heat input 35 kW G20
(G30/G31)
20130
(21130)
F
F
F
F
FR
FR
FR
FR

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SERVICE Manual City Class F-FR
PCB Code
PCB Code is placed close to the control panel and it is visible leaving metal cover
PCB boiler combustion automatic check
• On every boiler electrical switching ON, PCB starts
• An automatic procedure for setting Boiler Combustion, which is equal to 3rd digit of PCB Code, on left corner of Control
Panel (i.e. 1 on picture for F model).
• If boiler feels air pressure switch changing its status, it sets 3rd digit to 1
• If boiler feels Flues Thermostat contact closed, it sets 3rd digit to 0
• If boiler does not receive any feedback in a one minute, it shows E72
(Combustion Boiler error).
FFR
Digits 1st 2nd 3rd 4th 5th
Value Aestethic Gas Type Power Hydraulic Not used
City Class F
City Class FR
City Class FR
City Class F
City Class FR
City Class F

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SERVICE Manual City Class F-FR
PCB boiler combustion reset
PCB RESET = 2 parameters to factory setting a PCB code reset
It can be done only in first 3 min after switching ON (in case switch OFF and ON again the boiler).
It is advised for solving some puzzling problem on the field.
• Boiler Mode OFF
• Keep pressing for 15 sec buttons and RESET
• When display shows ,the PCB RESET has done.
PCB code Configuration
Once replaced PCB or after «PCB RESET» procedure, boiler has to be configured for model where it is mounted.
• Display shows
• Turn knob at least for 3/4 of its total range. This way is set Boiler Aesthetic, which is equal to 1st digit of Configuration
Code, on left corner of Control Panel (i.e. 2 on picture)
• Display shows
• Turn knob or choosing value = 2 and press RESET button for storing information. This way is set Boiler Hydraulic,
which is equal to 4th digit of Configuration Code, on left corner of Control Panel
• Ending, PCB shows Configuration done.
On display and on the sticker there must be the same Configuration Code
FFR

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SERVICE Manual City Class F-FR
Check list first ignition
Installation done under country regulation in force done
Flues and air system
Verify the length of exaust flue system,and verify the installation of reducer for short
system if needed (supplied with boielr’s documentation)
No leakage between part of the system (extension, bends and flanges)
Avoiding flues recirculation, respecting the minimum distances between the flues
and air pipes with split configuration and between air/flues pipe and walls with the
concentric configuration
Hydraulic plant
Correct plant pressure with cold system temperature
Ensuring air bleeding
Checking tank connection (only FR).
If tanF is not present, be sure to connect the flow and return together with a pipe for
ensuring the needed circulation
Gas plant
Checking inlet pressure
Static……………………….
Dynamic …………………….
Avoiding gas leakage from the gas connection on the boiler
Electric connection
Checking correct electric supply (220-240V -15%...+10% 50Hz)
Checking the correct tank probe connection (only FR), after having removed the
factory-installed resistor
Condense syphon
Checking syphon cleanness (no obstructions on it)
Connecting to a waste water or treating its acidity with relevant products
before discharging on the environment.
Flue check
Checking CO2 value
CO2 Qr ………………..
CO2 Qn ………………..
If CO2 values are not correct, do the procedure “Manual Calibration”.
FFR

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SERVICE Manual City Class F-FR
User Guide
The front control panel: PUSHBUTTONS AND KNOBS
Stand-by / Functioning mode
At every press, the boiler switches its mode from to
summer or winter mode.
00357 00
CH setting knob
To set the CH system temperature. If the Outdoor Sensor
Kit was installed, see also “Outdoor Sensor Kit”
DHW setting knob
To set the DHW temperature.
RESET Press to reset the boiler in case of breakdown.
See further details in “Alarms - boiler block”
DISPLAY - symbols enabled in this model and their description
CH – winter mode indication
If flashing, it means that the boiler is functioning in CH mode. See also the remark in the descrition
of symbol .
Burner ON
It indicates the presence of the flame in the burner.
DHW mode indication
If flashing, it means that the boiler is functioning to produce domestic hot water.
If both and symbols flash at the same time, a Technician-reserved function has been activated.
In this case, turn immediately the boiler off - and then turn it on again- by means of the button .
Two digit display under the symbol
Normally, it displays the CH flow temperature, i.e the temperature of the liquid on boiler’s outlet that is sent to
the CH system.
During the CH temperature setting (by rotating the knob ), it shows the temperature value changing; in
case of alarm it displays “E”; during the setting (reserved to the Technician) it displays the chosen parameter
ID number (see “PCB parameters settings (technician menu)”
Three digit display under the symbol
Normally, it displays the temperature of the hot water on boiler’s outlet. When the boiler is in stand-by mode,
it displays .
During the DHW temperature setting (by rotating the knob ), it shows the temperature value changing; in
case of alarm it displays the ID number of the alarm (see “Alarms - boiler block” on page<?>); during the
setting (reserved to the Technician) it displays the value of the chosen parameter.
RESET It appears when the boiler is locked or anyway is present an error that the user could manage. See “Alarms -
boiler block” to identify the problem and the relevant actions to be carried out.
SERVICE It appears when the boiler has detected an error (mainly a fault) that has to be managed by the Technician. The
User can anyway see “Alarms - boiler block” to get information about and the eventual actions to be carried
out.
It informs that the outdoor probe (accessories) is installed.
Note: In this case the CH system temperature is automatically set and so the use of the knob is different
from the standard way: for deeper details rely on kit instruction and see “Outdoor Sensor Kit”
FFR

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SERVICE Manual City Class F-FR
Access to the inside of the boiler
fUnscrew the casing fixing screws1 and2;
fpull the casing3 outwards, then push it upwards (to unhooF it from the tongues4) and remove it;
funscrew the screw5, then slide the control panel6 upwards and overturn it downwards;
fafter the regulations, close the boiler repeating everything in the other sense, carefully hooking the casing3 to the tongues4.
FFR
(some items of this picture, not involved
in the descripon, could be dierent from
the model that you are operang on)

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SERVICE Manual City Class F-FR
Boiler internal components 20 F - 25 F - 30 F
1 Flue pressure switch
2 Flue hood
3 Expansion vessel
4 Flame ignition/detection electrode
5 Safety thermostat on system flow
6 Temperature Sensor, system flow
7 Motorized 3-way valve
8 Automatic Venting Device
(heating circuit, incorporated in the pump)
9 Safety valve 3 bar
10 Pump
11 Drain valve
12 Priority flow switch (with filter)
13 Loss of water pressure switch
14 Gas valve
15 DHW temperature sensor
16 System pressure gauge
17 Filling valve
18 By-pass (in-built in the 3-way valve hydraulic
assembly)
19 DHW exchanger (thermally insulated)
20 Burner
21 Primary exchanger
22 Sealed chamber
23 Fan
F
1416
1517 13
12
11
18
7
21
22
23
20
6
5
19
3
7
5
6
4
8
10
9
1
2
00353 00

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SERVICE Manual City Class F-FR
Boiler internal components 20 FR - 25 FR - 30 FR
1 Flue pressure switch
2 Flue hood
3 Expansion vessel
4 Flame ignition/detection electrode
5 Safety thermostat on system flow
6 Temperature Sensor, system flow
7 Motorized 3-way valve
8 Automatic Venting Device
(heating circuit, incorporated in the pump)
9 Safety valve 3 bar
10 Pump
11 Drain valve
12 Loss of water pressure switch
13 Gas valve
14 System pressure gauge
15 By-pass (in-built in the 3-way valve hydraulic
assembly)
16 Burner
17 Primary exchanger
18 Sealed chamber
19 Fan
FR
1314 12 11
15
7
17
18
19
16
6
5
3
7
5
6
4
8
10
9
1
2
00385 A 00

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SERVICE Manual City Class F-FR
Boiler internal components 35 F
1 Flue pressure switch
2 Flue hood
3 Expansion vessel
4 Flame ignition/detection electrode
5 Safety thermostat on system flow
6 Temperature Sensor, system flow
7 Motorized 3-way valve
8 Automatic Venting Device
(heating circuit, incorporated in the pump)
9 Safety valve 3 bar
10 Pump
11 Drain valve
12 Priority flow switch (with filter)
13 Loss of water pressure switch
14 Gas valve
15 DHW temperature sensor
16 System pressure gauge
17 Filling valve
18 By-pass (in-built in the 3-way valve hydraulic
assembly)
19 DHW exchanger (thermally insulated)
20 Burner
21 Primary exchanger
22 Sealed chamber
23 Fan
F
1416
1517 13
12
11
18
7
21
22
23
20
6
5
19
3
7
5
6
4
8
10
9
1
2
00360 00

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SERVICE Manual City Class F-FR
Boiler internal components 35 FR
1 Flue pressure switch
2 Flue hood
3 Expansion vessel
4 Flame ignition/detection electrode
5 Safety thermostat on system flow
6 Temperature Sensor, system flow
7 Motorized 3-way valve
8 Automatic Venting Device
(heating circuit, incorporated in the pump)
9 Safety valve 3 bar
10 Pump
11 Drain valve
12 Loss of water pressure switch
13 Gas valve
14 System pressure gauge
15 By-pass (in-built in the 3-way valve hydraulic
assembly)
16 Burner
17 Primary exchanger
18 Sealed chamber
19 Fan
FR
1314 12 11
15
7
17
18
19
16
6
53
7
5
6
4
8
10
9
1
2
00385 B 00

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SERVICE Manual City Class F-FR
Hydraulic components F
1 Flue pressure switch
2 Flue hood
3 Expansion vessel
5 Safety thermostat on system flow
6 Temperature Sensor, system flow
7 Motorized 3-way valve
8 Automatic Venting Device
(heating circuit, incorporated in the pump)
9 Safety valve 3 bar
10 Pump
11 Drain valve
12 Priority flow switch (with filter)
13 Loss of water pressure switch
14 Gas valve
15 DHW temperature sensor
16 System pressure gauge
17 Filling valve
18 By-pass (in-built in the 3-way valve hydraulic
assembly)
19 DHW exchanger (thermally insulated)
20 Burner
21 Primary exchanger
22 Sealed chamber
23 Fan
30 Check valve
R Heating return
M Heating flow
C Hot water outlet
F Cold water inlet
G Gas inlet
F
00355 00
M
22
23
18
17
21
20
13
10
8
3
9
11
1
7
6
5
2
14
19
15
30
RM CF G
12
16

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SERVICE Manual City Class F-FR
Hydraulic components FR
1 Flue pressure switch
2 Flue hood
3 Expansion vessel
5 Safety thermostat on system flow
6 Temperature Sensor, system flow
7 Motorized 3-way valve
8 Automatic Venting Device
(heating circuit, incorporated in the pump)
9 Safety valve 3 bar
10 Pump
11 Drain valve
12 Loss of water pressure switch
13 Gas valve
14 System pressure gauge
15 By-pass (in-built in the 3-way valve hydraulic
assembly)
16 Burner
17 Primary exchanger
18 Sealed chamber
19 Fan
R Heating return
M Heating flow
RBReturn from storage coil
MB Flow to storage coil
G Gas inlet
FR
00384 00
M
RMRB MB G
3
14
16
17
18
19
15
7
9
11
10
8
13
7
6
5
2
1

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SERVICE Manual City Class F-FR
Electrical diagram F
1 Flue pressure switch (*)
4 Flame ignition/detection electrode
5 Safety thermostat on system flow (*)
6 Temperature Sensor, system flow
7 Motorized 3-way valve
10 Pump
12 Priority flow switch (with filter) (*)
13 Loss of water pressure switch (*)
14.1 Gas valve - modulation control
14.2 Gas valve - opening control
15 DHW temperature sensor
23 Fan
41 Fuse F2A (2A fast)
(*) the contacts of these components are shown
in rest conditions (cold condition, no system
pressure, no flow)
Optional external devices:
TA Room thermostat: (or Chronothermostat) SELV
simple contact. Closed contact = heating request.
or Remote control (original accessory only)
SE To optional outdoor temperature sensor
Abbreviations: COMCommon •NCNormally
closed (contact) •NONormally open (contact)
•HEAHeating (diverting command) •DHWHot
water (diverting command)
Colours: BFBlacF •BNBrown •BUBlue ●GNGreen
•RDRed •OGOrange •VTViolet •WHWhite
•YEYellow •YGYellow-Green
F
12 43
PE NL
M0101 M0102 M0901 M0900
M0904
NC
NO
NC
NO
3
4
2
1
YG
BN
BU
3 DHW 2 COM 1 HEA
WH
BK BK
RD
BU BU BK
BK
OG OG
VT VT
GN GN
WH WH
BU BU
RD
BN
YG
BU
BN
BU BU
BN
BK
41
7115
6
12
5
13
14.2
14.1
10
23
00354 INT 01
LN
SE
TA
4

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SERVICE Manual City Class F-FR
Electrical diagram FR
1 Flue pressure switch (*)
4 Flame ignition/detection electrode
5 Safety thermostat on system flow (*)
6 Temperature Sensor, system flow
7 Motorized 3-way valve
10 Pump
12 Loss of water pressure switch (*)
13.1 Gas valve - modulation control
13.2 Gas valve - opening control
19 Fan
41 Fuse F2A (2A fast)
42 Resistor, 2.2 FOhm - 1/2W (**)
(*) the contacts of these components are shown in
“standard” conditions (i.e. temperature below
threshold, cold system, no system pressure, no
flow)
(**)see “Electrical connection between the boiler and
the storage unit”for details.
Optional external devices:
SP DHW Storage temperature Probe (**)
ST DHW Storage Thermostat (*) (**)
TA Room thermostat: (or Chronothermostat) SELV
simple contact. Closed contact = heating request.
or Remote control (original accessory only)
SE To optional outdoor temperature sensor
Abbreviations: COMCommon •NCNormally
closed (contact) •NONormally open (contact)
•HEAHeating (diverting command) •DHWHot
water (diverting command)
Colours: BFBlacF •BNBrown •BUBlue
•GNGreen •RDRed •OGOrange
•VTViolet •WHWhite •YEYellow
•YGYellow-Green
FR
12 43
PE NL
M0101 M0102 M0901 M0900
M0904
NC
NO
NC
NO
3
4
2
1
YG
BN
BU
3 DHW 2 COM 1 HEA
WH
BK BK
RD
BU BU BK
BK
OG OG
VT VT
GN GN
BU BU
WH WH
BU
BU
WH
WH
RD
BN
YG
BU
BN
BU BU
BN
BK
41
71
6
5
12
13.2
13.1
10
19
003383 01
LN
SE
TA
4
SP
ST
42
(SP)
(ST)

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SERVICE Manual City Class F-FR
Heating system filling and pressuring
Once all system connections have been carried out,
proceed with system filling. This operation should be
made with care, respecting the following steps:
fOpen the radiators venting devices;
fCheck that the plug of the automatic air vent, incor-
porated in the boiler circulator, is unscrewed: if not,
unscrew it and leave it unscrewed, even afterwards,
for normal operation;
fIf it’s required to fill the system with anti-freeze
solution, do this operation, then hermetically close
the connection or the valve used to put the solution
in, to allow the pressurization.
fGradually open the filling cock 2 ;
fCheck the correct functioning of automatic venting
devices, eventually installed;
fClose the radiators venting devices as soon as water flows out of them;
fMake sure, by reading the pressure gauge 1, that the pressure reaches the optimal value of 1.0 bar (max 1.5
bar);
fClose the water filling cock 2 and bleed each radiator again;
fRepeat the venting and pressurization operations until the air is completely purged from the system.
F
00316_00
2
3
4
1

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SERVICE Manual City Class F-FR
FR
Heating system filling and pressuring
Once all system connections have been carried out,
proceed with system filling. This operation should be
made with care, respecting the following steps:
fOpen the radiators venting devices;
fCheck that the plug of the automatic air vent, incor-
porated in the boiler circulator, is unscrewed: if not,
unscrew it and leave it unscrewed, even afterwards,
for normal operation;
fLocate the system filling device, foreseen externally
to the boiler, and proceed depending on its type:
- filling from aqueduct: open it and let water flow in the system
- filling with anti-freeze solution: pump in the solution and pressurize the system.
fCheck the correct functioning of automatic venting devices, eventually installed on the heating system and/
or on the storage coil circuit;
fClose the radiators venting devices as soon as water or anti-freeze solution flows out of them;
fIf the storage coil or the relevant circuit were equipped with manual venting valves, use them to purge the
residual air from them;
fMake sure, by reading the pressure gauge 1, that the pressure reaches the optimal value of 1.0 bar (max
1.5 bar);
fClose the filling device and bleed each radiator again;
fRepeat the venting and pressurization operations until the air is completely purged from the system.
DHW storage tank filling
Fill the DHW storage tank (on storage unit):
fopen one of the hot water taps in the DHW system;
fgradually open the hand valve installed on the cold water inlet of the storage unit;
fwhen only water flows out of the tap, close it.
00337_00
3
4
1

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SERVICE Manual City Class F-FR
DHW exchanger FFR

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SERVICE Manual City Class F-FR
FLOW STAT TOOLS
tools suggested: allen Fey 4 mm - antiscale liquid for cleaning
DISMOUNTING
• discharge boiler water from both side (DHW and CH) see procedure
• rotate safety 3 bar (D) 90* clockwise to show the right fixing screw by hands
• unscrew 2 fixing screws (F) allen key 4 mm
• take out the DHW exchanger (H) by hand
• clean chemically or to replace it by hand
HOW TO CLEAN
• chemical cleaning with antiscale liquid on both sides of DHW exchanger
• rinse thoroughly with water
MOUNTING
• check effectiveness of 4 O-rings (G) by hands
• place DHW exchanger on its spot by hands
• screw 2 fixing screw (F) allen key 4 mm
• rotate safety 3 bar (D) 90° anticlockwise and connect its discharging pipe if it is the case by hands
• fill-in boiler water see procedure
FLOW STAT
tools suggested: allen key 4 mm - cross screwdriver
DISMOUNTING
• place flow stat to its spot on brass group by hands
• screw 2 fixing screws (A) to hydraulic metal bracket cross screwdriver
• screw 1 fixing screw (B) to brass group cross screwdriver
• rotate safety 3 bar (D) 90° anticlockwise and connect its discharging pipe if it is the case by hands
• plug flow stat electrically (C) by hands
• fill-in boiler with water see procedure
MOUNTING
• discharge water from DHW side see procedure
• unplug flow stat electrically (C) by hands
• rotate safety 3 bar (D) 90* clockwise to show the flow stat behind by hands
• unscrew 2 fixing screws (A) from hydraulic metal bracket cross screwdriver
• unscrew 1 fixing screw (B) from brass group cross screwdriver
• unscrew 1 screw (E) and to screw it where screw (B) has been left; this way flow stat will
leave easily its spot from brass group allen key 4 mm
• screw 1 screw (E) on the previous spot for future servicing allen key 4 mm
3 WAY VALVE
tools suggested: wrench 14 mm or 3/8” - wrench 30 mm or ¾”- allen key 4 mm - cross screwdriver -socket wrench 34 mm
DISMOUNTING
• discharge boiler water from both side (DHW and CH) see procedure
• dismount pipe (Q) wrench 30 mm
• dismount manometer (I) wrench 14 mm
• dismount DHW exchanger (H) (see procedure) allen Fey 4 mm
• unscrew 2 fixing screws (L) and take out the brass group (I) cross screwdriver
• unscrew plastic nut (O) and take out first half of 3 way valve wrench 30 mm
• unscrew brass nut (P) and take out second half of 3 way valve socket wrench 34 mm
• clean or to replace 3 way valve by hands
MOUNTING
• mount of 3 way valve, tightening plastic nut (O) and brass nut (P) wrench 30 mm - socket wrench
34 mm
• place brass group on the bracFet and fix it with 2 screws (L) but not tighten them completely by hands
• mount DHW exchanger (H) (see procedure) allen key 4 mm
• mount pipe (Q) wrench 30 mm
• fix completely 2 screws (L) cross screwdriver
• mount manometer (R) wrench 14 mm
• fill-in boiler with water see procedure
FFR
Dismounting & mounting

Green Heating Technology
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SERVICE Manual City Class F-FR
Combustion components FFR