Strebel S-CBX 85 User manual

STREBEL
S-CBX Boiler Range
Models 85 - 105 - 125 - 155
Wall Hung High Efficiency Condensing Boiler
Installation, Operating & Maintenance Manual
Please read and understand before commencing installation and leave the manual with the customer for future reference.
2019-02-01 v2

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TABLE OF CONTENTS
1INTRODUCTION .................................................................................................................................. 7
1.1 EXPLANATION OF TYPE/MODEL NUMBER. .................................................................................... 7
2SAFETY GUIDELINES, ........................................................................................................................ 7
3TECHNICAL DATA for S-CBX BOILERS ........................................................................................... 8
3.1 FUNCTIONAL INTRODUCTION ...................................................................................................... 8
3.2 LOCATION OF VERSION NUMBERS ............................................................................................... 8
3.2.1 Technical specifications datasheet ............................................................................... 9
3.3 ERP SPECIFICATIONS DATASHEET ........................................................................................... 11
4DIMENSIONS & CONNECTIONS ...................................................................................................... 12
4.1 S-CBX 85 & 105 .................................................................................................................... 12
4.2 S-CBX 125 ............................................................................................................................ 13
4.3 S-CBX 155 ............................................................................................................................ 14
5ACCESSORIES AND UNPACKING .................................................................................................. 15
5.1 ACCESSORIES ......................................................................................................................... 15
5.2 UNPACKING ............................................................................................................................ 15
6INSTALLATION OF THE S-CBX ....................................................................................................... 16
6.1 INSTALLATION CLEARANCES .................................................................................................... 16
6.2 BOILER INSTALLATION LOCATION REQUIREMENTS ..................................................................... 16
6.3 MOUNTING THE BOILER ............................................................................................................ 17
7CONNECTIONS ................................................................................................................................. 18
7.1 BOILER CONNECTIONS ............................................................................................................. 18
7.2 CONDENSATE DRAIN CONNECTION ........................................................................................... 18
7.3 FLOW AND RETURN CONNECTIONS ........................................................................................... 19
7.4 THE EXPANSION VESSEL .......................................................................................................... 19
7.5 PRESSURE RELIEF VALVE......................................................................................................... 19
7.6 NON-RETURN VALVE. ............................................................................................................. 20
7.7 BYPASS .................................................................................................................................. 20
7.8 PUMP FUNCTIONALITY ............................................................................................................. 20
7.9 FROST PROTECTION ................................................................................................................ 20
7.10 INSTALLING A STRAINER AND/OR DIRT SEPARATOR .................................................................... 21
7.11 WATER QUALITY ...................................................................................................................... 21
7.12 USE OF GLYCOL ...................................................................................................................... 22
7.13 CHEMICAL WATER TREATMENT ................................................................................................. 22
7.14 FLUSH THE SYSTEM WITH FRESH WATER ................................................................................... 23
7.15 PLASTIC PIPING IN THE HEATING SYSTEM .................................................................................. 23
7.16 DE-AIR SEQUENCE. ................................................................................................................. 24
7.17 AUTOMATIC FEED VALVE SYSTEMS .......................................................................................... 24
7.18 WATER PRESSURE .................................................................................................................. 25
7.19 INSTALLATION EXAMPLES ......................................................................................................... 25
7.19.1 Example of a normal single boiler heating circuit with low loss header (preferable) . 25
7.19.2 Example of a multiple boiler heating circuit with low loss header .............................. 26
8PUMP CHARACTERISTICS .............................................................................................................. 27
8.1 HYDRAULIC GRAPHS ................................................................................................................ 27
8.2 MODULATING PUMP FOR CH DEMAND ....................................................................................... 28
8.3 MODULATING PUMP MODES ...................................................................................................... 29
8.3.1 Delta temperature modulation .................................................................................... 29
8.4 PUMP: MAXIMUM ELECTRICAL POWER ....................................................................................... 29
9FLUE GAS AND AIR SUPPLY SYSTEM .......................................................................................... 30
9.1 GENERAL ................................................................................................................................ 30
9.2 POLYPROPYLENE .................................................................................................................... 31
9.2.1 Flexible polypropylene ...................................................................................................... 31
9.3 STAINLESS STEEL VENT. .......................................................................................................... 31
9.4AIR SUPPLY ............................................................................................................................ 32
9.4.1 Combustion air quality ................................................................................................ 32
9.4.2 Air supply through humid areas .................................................................................. 32
9.4.3 Air inlet pipe materials ................................................................................................ 32
9.5 ROOM AIR ............................................................................................................................... 32

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9.5.1 Air contamination ........................................................................................................ 32
9.6 PROPER VENT INSTALLATION AND TYPE OF GAS VENT OR VENT CONNECTOR. .............................. 33
9.7 BOILER CATEGORIES - TYPES OF FLUE GAS SYSTEMS. ................................................................ 34
9.8 C63 CERTIFIED ........................................................................................................................ 38
9.9 PIPE HEIGHTS AND MUTUAL DISTANCES ON A FLAT ROOF ............................................................ 39
9.10 FLUE TERMINAL POSITIONING .................................................................................................. 40
9.11 HORIZONTAL FLUE RUN RISK ASSESSMENT .............................................................................. 41
9.11.1 Figure 12 – line G ....................................................................................................... 42
9.12 FLUE GAS AND AIR SUPPLY RESISTANCE TABLE .......................................................................... 43
9.13 TYPICAL EXAMPLES .................................................................................................................. 45
9.13.1 Example A: Twin pipe system with separate pipes for flue outlet and air supply ....... 45
9.13.2 Example B: Twin pipe system with concentric roof terminal ....................................... 46
9.13.3 Example C: Single flue gas outlet. Air supply from boiler room.................................. 48
9.13.4 Example D: Concentric flue gas/air supply pipe (roof-mounted) ................................ 49
9.13.5 Example E: Concentric system Wall outlet C13 (wall-mounted) ................................ 49
10 CASCADING ....................................................................................................................................... 51
10.1 APPLIANCE .............................................................................................................................. 51
11 ELECTRICAL INSTALLATION .......................................................................................................... 52
11.1 GENERAL ................................................................................................................................ 52
11.2 ELECTRICAL CONNECTIONS ...................................................................................................... 52
11.3 EXPLANATION OF THE LOW VOLTAGE CONNECTIONS. ................................................................. 53
11.4 EXPLANATION OF THE HIGH VOLTAGE CONNECTIONS.................................................................. 54
11.5 LADDER/LOGIC DIAGRAM ......................................................................................................... 55
11.6 ELECTRICAL SCHEMATICS ........................................................................................................ 56
11.7 SENSOR AVAILABILITY .............................................................................................................. 58
11.8 NTC SENSOR CURVE ............................................................................................................... 58
11.9 PROGRAMMABLE IN- AND OUTPUTS ........................................................................................... 59
12 BURNER CONTROLLER AND DISPLAY. ........................................................................................ 60
12.1 DISPLAY AND BUTTONS ............................................................................................................ 60
12.1.1 Display icons ............................................................................................................... 61
12.2 SCREENS AND SETTINGS. ......................................................................................................... 61
12.2.1 Set Actual setpoint/DHW setpoint directly via the Status overview ............................ 61
12.2.2 Entering the menu ....................................................................................................... 62
12.2.3 Protected menu items ................................................................................................. 63
12.2.4 De-aeration Sequence ................................................................................................ 63
12.2.5 Language settings ....................................................................................................... 63
12.3 BOILER HISTORY ...................................................................................................................... 64
12.4 ERROR LOGGING. .................................................................................................................... 64
12.5 GENERAL ................................................................................................................................ 65
12.5.1 Pump start exercise every 24 hours ........................................................................... 65
12.5.2 Frost protection ........................................................................................................... 65
12.5.3 Appliance selection ..................................................................................................... 66
12.6 IGNITION CYCLE ....................................................................................................................... 66
12.6.1 Flame detection .......................................................................................................... 67
12.6.2 Flame recovery ........................................................................................................... 67
12.7 CONTROL FUNCTIONS .............................................................................................................. 68
12.7.1 Room thermostat only; CH mode 0 (Default setting) .................................................. 68
12.7.2 CH with an outdoor temperature reset and THERMOSTAT; CH mode 1 .................. 69
12.7.3 CH with constant circulation system outdoor RESET; CH mode 2 ............................ 71
12.7.4 CH with constant circulation and permanent heat demand; CH mode 3 .................... 71
12.7.5 Central Heating with analogue input control of setpoint; CH mode 4 ......................... 72
12.7.6 CH with analogue input control of power output; CH mode 5 ..................................... 73
12.8 DEMAND FOR DOMESTIC HOT WATER ...................................................................................... 74
12.8.1 No Domestic Hot Water; DHW mode 0 ...................................................................... 74
12.8.2 DHW Storage with sensor; DHW mode 1 ................................................................... 74
12.8.3 DHW Storage with thermostat; DHW mode 2............................................................. 75
12.8.4 Instantaneous water heating with plated heat exchanger; DHW mode 3 ................... 75
12.8.5 Anti-legionella protection............................................................................................. 76
12.8.6 Display menu structure summary. .............................................................................. 77
13 TEMPERATURE PROTECTION ........................................................................................................ 84
14 ERROR INFORMATION. .................................................................................................................... 85

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14.1 BOILER HISTORY. .................................................................................................................... 85
14.2 BOILER HISTORY AND TIME STAMPS BOILER HISTORY ................................................................ 85
14.3 LOCKOUT CODES..................................................................................................................... 86
14.4 BLOCKING CODES ................................................................................................................... 89
14.5 WARNINGS ............................................................................................................................. 91
15 CASCADING ...................................................................................................................................... 92
15.1 SYSTEM SETUP ....................................................................................................................... 92
15.2 BOILER CASCADE COMMUNICATION SETUP. ............................................................................... 92
15.2.1 Setting up the cascade parameters: ....................................................................... 93
15.2.2 Cascade – Heating only Managing boiler .................................................................. 94
15.2.3 Cascade – Domestic Hot Water Settings ................................................................... 95
15.2.4 Cascade – DHW priority ............................................................................................. 95
15.2.5 Cascade – Start/stop sequence ................................................................................. 95
15.2.6 Cascade – Power balance mode ............................................................................... 97
15.2.7 Power mode = 1 (Minimum boilers on) ...................................................................... 98
15.2.8 Power mode 2 – Maximum burners on ...................................................................... 99
15.2.9 Power mode 3 – Balanced burners on ....................................................................... 99
15.3 BOILER ROTATION ................................................................................................................. 100
15.3.1 Next depending to start selection ............................................................................. 100
15.4 CASCADE ERROR HANDLING ................................................................................................. 101
15.4.1 Cascade Frost protection ......................................................................................... 101
15.4.1 Emergency mode ..................................................................................................... 101
15.4.2 Managing boiler error ............................................................................................... 101
16 SYSTEM TEST. ................................................................................................................................ 102
17 COMMISSIONING THE BOILER ..................................................................................................... 103
17.1 FIRST: FLUSHING THE BOILER WITH WATER ............................................................................. 103
17.2 SECOND: FILLING & VENTING THE BOILER AND THE SYSTEM ..................................................... 103
17.3 THIRD: CHECK THE WATER FLOW ............................................................................................ 103
17.4 MOUNTING CONDENSATE TRAP ............................................................................................. 104
17.5 CHECKING GAS PRESSURE..................................................................................................... 104
17.6 FIRING FOR THE FIRST TIME ................................................................................................... 104
18 ADJUSTING AND SETTING THE BOILER ..................................................................................... 105
18.1 INTRODUCTION ...................................................................................................................... 105
18.1.1 Combustion table...................................................................................................... 105
18.1.2 Setting screws venturi- and gas valves: drawings ................................................... 106
18.2 ADJUSTMENT PROCEDURES ................................................................................................... 107
18.3 VENTURI REPLACEMENT ADJUSTMENT ................................................................................... 107
18.4 CONVERSION FROM NATURAL GAS TO PROPANE ..................................................................... 108
18.5 START UP CHECKLIST ........................................................................................................... 111
19 INSPECTION, MAINTENANCE AND SERVICE.............................................................................. 113
19.1 GENERAL .............................................................................................................................. 113
19.2 INSPECTION, MAINTENANCE AND SERVICE. .............................................................................. 113
19.2.1 Mounting the burner door ......................................................................................... 120
19.3 MAINTENANCE CHECKLIST ..................................................................................................... 121
20 USER INSTRUCTIONS .................................................................................................................... 122
21 INSTALLATION EXAMPLES ........................................................................................................... 123
22 USER’S PART. ................................................................................................................................. 127
22.1 EXPLANATION OF TYPE/MODEL NUMBER. ................................................................................ 127
22.2 SAFETY GUIDELINES. ............................................................................................................. 127
22.3 TO TURN OFF GAS TO THE APPLIANCE ..................................................................................... 127
22.4 MAINTENANCE AND INSPECTION ............................................................................................. 127
22.5 DISPLAY AND BUTTONS .......................................................................................................... 128
22.6 DISPLAY ICONS ..................................................................................................................... 129
22.7 STARTING THE BOILER. .......................................................................................................... 129
22.8 CHANGING THE SETPOINT AND/OR ENABLING CH/DHW. ......................................................... 130
22.8.1 Changing the Central Heating setpoint directly. ....................................................... 130
22.8.2 Changing the DHW setpoint directly. ....................................................................... 130
22.8.3 Enable / Disable CH or DHW control. ...................................................................... 130
22.9 THE MENU (BUTTON). .......................................................................................................... 131
22.10 PASSWORD ........................................................................................................................... 131

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22.11 LANGUAGE SETTING ............................................................................................................... 131
22.12 AVAILABLE MENU ITEMS ......................................................................................................... 131
22.12.1 Central Heating (CH) ................................................................................................ 132
22.12.2 Domestic Hot Water (DHW) ...................................................................................... 132
22.12.3 Information ................................................................................................................ 132
22.12.4 Software Versions ..................................................................................................... 132
22.12.5 Boiler Status .............................................................................................................. 132
22.12.6 Boiler History ............................................................................................................. 132
22.12.7 Error log .................................................................................................................... 132
22.12.8 Service ...................................................................................................................... 133
22.12.9 Settings ..................................................................................................................... 133
22.12.10 General Settings ....................................................................................................... 133
22.12.11 Language .................................................................................................................. 133
22.12.12 Unit Type ................................................................................................................... 133
22.12.13 Date & Time .............................................................................................................. 133
22.12.14 Time zone settings .................................................................................................... 133
22.12.15 Display settings ......................................................................................................... 133
22.12.16 Cascade mode .......................................................................................................... 133
22.12.17 Other Settings ........................................................................................................... 134
22.12.18 Boiler settings ........................................................................................................... 134
22.13 BOILER HISTORY ................................................................................................................... 134
22.14 ERROR LOGGING ................................................................................................................... 134
22.15 SERVICE REMINDER ............................................................................................................... 135
22.15.1 Service overdue logging ........................................................................................... 135
22.15.2 Service reminder implementations ........................................................................... 135
22.15.3 Reset the service reminder ....................................................................................... 135
22.15.4 Menu’s and parameters ............................................................................................ 135
22.16 SYSTEM TEST ........................................................................................................................ 136

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1 INTRODUCTION
This manual is written for:
▪ The Installer.
▪ System Design Engineer.
▪ The service Engineer.
▪ The user (see chapter 22).
Strebel Ltd are not accountable for any damage caused by incorrect following these instructions. For service and
repair purposes use only original Strebel Ltd spare parts.
All documentation produced by the manufacturer is subject to copyright law.
1.1 Explanation of type/model number.
CB = Condensing Boiler
HW = For Direct Hot Water (drinking water) usage only.
CH = Central Heating (for central heating purposes and/or indirect hot water)
2 SAFETY GUIDELINES,
“FOR YOUR SAFETY READ BEFORE OPERATING”
A. This appliance does not have a pilot. It is equipped with an ignition device which automatically lights the
burner. Do not try to light the burner by hand.”
B. BEFORE OPERATING smell all around the appliance area for gas. Be sure to smell next to the floor because
some gas is heavier than air and will settle on the floor.”
C. Do not use this appliance if any part has been under water. Immediately call a qualified service technician to
inspect the appliance and to replace any part of the control system and any gas control which has been
under water.”
What to do if you smell gas:
▪ Do not use any electrical equipment.
▪ Do not press any switches.
▪ Close the gas supply.
▪ Ventilate the room (open the windows and/or outdoor water heater room doors).
▪ Immediately warn the installer.
The manufacturer/supplier is not liable for any damage caused by inaccurately following of these
mounting instructions. Only original parts may be used when carrying out any repair or service works.
This appliance is not intended for use by persons (including children) with reduced physical, sensory or
mental capabilities, or lack of experience and knowledge, unless they have been given supervision or
instruction concerning use of the appliance by a person responsible for their safety. Children should be
supervised to ensure that they do not play with the appliance.
“WARNING: Improper installation, adjustment, alteration, service or maintenance can cause property
damage, personal injury (exposure to hazardous materials) * or loss of life. Installation and service must be
performed by a qualified installer, service agency or the gas supplier (who must read and follow the supplied
instructions before installing, servicing, or removing this water heater.

8
3 TECHNICAL DATA FOR S-CBX BOILERS
3.1 Functional introduction
The S-CBX boilers are central heating boilers with a maximum high efficiency. Such a performance can be reached
by, amongst other things, using a special heat exchanger made of stainless steel. This allows the flue gases to cool
down below the condensation point, and so release extra heat. This has an immediate positive impact on the
efficiency.
The S-CBX boiler is standard set for Natural Gas (G20).
Fuel used should have sulphur rates with a maximum annual peak over a short period of time of 150 mg/m3 and an
annual average of 30 mg/m3.
Boiler control includes:
▪ Cascade control for up to sixteen boilers.
▪ Remote operation and heat demand indication from each boiler.
▪ Weather compensation control.
▪ Calorifier control.
Connections for:
▪ On/Off thermostat.
▪ 0-10 VDC remote flow temperature (set point)
control.
▪ 0-10 VDC remote burner input control.
▪ Outdoor temperature sensor.
▪ External calorifier pump or diverter valve.
▪ Boiler pump.
▪ PWM control for external boiler pump.
▪ System pump.
▪ External flow switch or external safety device.
▪ Modbus.
▪ External system sensor.
▪ DHW indirect sensor or DHW control thermostat.
▪ Touchscreen.
▪ External Ignition transformer.
3.2 Location of version numbers
Burner Controller Hardware Version
– To be found on the second line of the white sticker on the side of the burner controller.
e.g. 957MN15_3Rh4a
Burner Controller Software Versions
– Press the menu button , go to Information and then to Software Versions.
Information
Software Versions
Boiler Status
Boiler History
Error Log
i
Software Versions
Display [63EF 83BC]
Boiler [5C79 14A9]
Device Group 900MN

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3.2.1 TECHNICAL SPECIFICATIONS DATASHEET
GENERAL
Product identification number:
0063CT3633
Classification
II2H3P
Gas Appliance Type
-
B23(P), C13, C33, C43, C63, C83, C93,
C(10)3, C(11)3, C(12)3, C(13)3, C(14)3, C(15)3
Boiler Model
S-CBX 85
S-CBX 105
S-CBX 125
S-CBX 155
Dimensions (h x w x d)
mm
845 x 440 x 530
Water content estimated
litre
5.0
6.5
8.3
10.4
Weight (empty)
kg
77
79
83
86
Flow/return connection (boiler)
inch
R 1”
R 1”
R 1”
R 1¼”
Gas connection
inch
R ¾”
R ¾”
R ¾”
R 1”
Flue connection twin pipe
mm
100
100
100
150
Flue connection concentric pipe
mm
100/150
100/150
100/150
N.A.
HEATING Values min-max:
Nominal input (gross) (G20)
kW
17.1 - 90.7
20.7 - 108.1
26.2 - 132.6
38.9 - 161.4
Nominal input (net) (G20)
kW
15.4 - 81.7
18.6 - 97.3
23.6 - 119.4
35.0 - 145.3
Nominal input (gross) (G25.3)
kW
17.4 - 88.6
20.8 - 105.7
26.4 - 129.7
39.3 - 158.0
Nominal input (net) (G25.3)
kW
15.7 - 79.7
18.7 - 95.2
23.8 - 116.9
35.4 - 142.2
Nominal input (gross) (G31)
kW
17.4 - 87.4
20.6 - 103.4
26.2 - 131.2
42.7 - 154.4
Nominal input (net) (G31)
kW
16.0 - 80.5
19.0 - 95.2
24.1 - 120.8
39.3 - 142.2
Nominal output 80/60 °C (G20)
kW
14.9 - 79.1
18.0 - 94.2
22.9 - 115.7
33.9 - 140.9
Nominal output 50/30 °C (G20)
kW
16.0 - 85.1
19.5 - 101.8
24.7 - 124.7
36.4 - 151.0
Nominal output 37/30 °C (G20)
kW
16.6 - 88.4
20.2 - 105.5
25.6 - 129.4
38.0 - 157.8
Nominal output 80/60 °C (G25.3)
kW
15.2 - 77.0
18.1 - 92.3
23.1 - 113.4
34.3 - 137.9
Nominal output 50/30 °C (G25.3)
kW
16.4 - 83.0
19.6 - 99.6
24.9 - 121.1
36.8 - 147.7
Nominal output 37/30 °C (G25.3)
kW
17.0 - 88.4
20.3 - 105.5
25.8 - 129.4
38.4 - 157.8
BOILER EFFICIENCY
Seasonal Efficiency (Part L) GV
%
95.62%
95.70%
95.68%
95.84%
Efficiency (input 30%, return
temperature 30 °C)
%
108.2%
108.4%
108.4%
108.6%
GAS CONSUMPTION Values min-max:
Natural gas (G20)
m3/h
1.6 – 8.5
1.9 – 10.2
2.5 – 12.5
3.7 – 15.3
Natural gas (G25.3)
m3/h
1.8 – 9.2
2.2 – 11.6
2.8 – 14.2
4.1 – 16.3
Propane (G31) 1
m3/h
0.6 – 3.2
0.8 – 3.9
1.0 – 4.8
1.6 – 5.7
Gas supply pressure
nominal 2
G20
mbar
20
G25.3
mbar
25
G31
mbar
37
NOTES
1 Using propane, a restriction needs to be placed and the maximum fan speed needs to be reduced
2 Min. and max. gas supply pressures:
p nom [mbar]
p min [mbar]
p max [mbar]
G20
20
17
25
G25.3
25
20
30
G31
37
25
57.5

10
Boiler Model
S-CBX 85
S-CBX 105
S-CBX 125
S-CBX 155
EMISSION Values min-max:
CO2 flue gas 3
G20
%
7.9 – 8.4
7.9 – 8.4
7.9 – 8.4
7.9 – 8.4
G25.3
%
8.4 – 8.2
8.4 – 8.2
8.4 – 8.2
8.4 – 8.2
G31
%
10 - 10
10 - 10
10 - 10
10 - 10
O2 flue gas 3
G20
%
6.9 - 6.0
6.9 - 6.0
6.9 - 6.0
6.9 - 6.0
G25.3
%
5.7 - 6.1
5.7 - 6.1
5.7 - 6.1
5.7 - 6.1
G31
%
5.7 - 5.7
5.7 - 5.7
5.7 - 5.7
5.7 - 5.7
NOx class
-
6
6
6
6
Flue gas temperature at combustion air
temperature = 20 °C
°C
60 - 90
Mass flow flue gas (min/max)
g/s
8.0 - 42
10 - 51
12 - 62
15 - 76
Available pressure for the flue system 4
Pa
200
INSTALLATION
Resistance boiler
T = 20 K
m.W.C
4.0
3.4
3.8
3.6
T = 25 K
m.W.C
2.8
2.3
2.5
2.4
Pressure boiler min-max.
bar
1.0 – 6.0
Max. flow temperature
°C
90
ELECTRIC
Maximum power consumption 5
W
190
280
280
280
Power supply
V/Hz
230 / 50
Protection class
-
IPX4D
NOTES
3 CO2 of the unit measured/set without the boiler front panel in place
4 Maximum allowed combined resistance of flue gas and air supply piping at high fire
5 Power consumption is measured without circulation pump

11
3.3 ErP Specifications Datasheet
Technical parameters according to the European ERP (Energy Related Products) legislation:
Type Boiler:
S-CBX 85
S-CBX 105
S-CBX 125
S-CBX 155
Condensing boiler:
Yes
Yes
Yes
Yes
Low temperature boiler:
No
No
No
No
B11 boiler:
No
No
No
No
Cogeneration space heater:
No
No
No
No
Combination heater:
No
No
No
No
Unit:
Value
Value
Value
Value
Rated heat output
kW
78.9
94.3
115.6
140.9
P-rated (P4) at 60-80 ⁰C
kW
78.9
94.3
115.6
140.9
Heat output (P1) 30% at 30-37 ⁰C
kW
25.2
31.6
38.8
46.5
Seasonal space heating energy
efficiency (ɳs).
%
92.4
92.6
92.7
92.9
Energy efficiency (ɳ4) at 60-80 ⁰C
%
87.2
87.2
87.3
87.3
Energy efficiency (ɳ1) at 30-37 ⁰C
%
97.4
97.6
97.7
97.8
Auxiliary electricity consumption
At full load (elmax).
kW
0.183
0.271
0.280
0.278
At part load (elmin)
kW
0.024
0.023
0.027
0.031
In standby mode (Psb)
kW
0.007
0.007
0.007
0.007
Other
Standby heat loss (Pstby)
kW
0.066
0.070
0.075
0.083
Ignition burner power consumption (Pign)
kW
0.000
0.000
0.000
0.000
Emissions (NOx) of nitrogen oxides
(EN15502-1:2012+A1:2015)1
mg/kWh
23.1
21.3
23.9
20.1
Sound power level, indoors
(EN 15036-1:2006)
dB
65.8
68.0
67.8
73.0
1 These numbers are used to assign credits according to the BREEAM standards

12
A
B
C
D
4 DIMENSIONS & CONNECTIONS
4.1 S-CBX 85 & 105
Twin Pipe Concentric / Coaxial
Connections
Twin Pipe
Concentric
A
Flow
BSP 1”
B
Return
BSP 1”
C
Condensate
Flexible hose Ø 25/21 mm
D
Gas
BSP ¾”
Flue gas
100 mm
100-150 mm
Air inlet
100 mm
100-150 mm

13
A
B
C
D
4.2 S-CBX 125
Twin Pipe Concentric / Coaxial
Connections
Twin Pipe
Concentric
A
Flow
BSP 1”
B
Return
BSP 1”
C
Condensate
Flexible hose Ø 25/21 mm
D
Gas
BSP ¾”
Flue gas
100 mm
100-150 mm
Air inlet
100 mm
100-150 mm

14
A
B
C
D
4.3 S-CBX 155
Twin Pipe Only
Connections
Twin Pipe
A
Flow
BSP 1¼”
B
Return
BSP 1¼”
C
Condensate
Flexible hose Ø 25/21 mm
D
Gas
BSP 1”
Flue gas
150 mm
Air inlet
150 mm

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5 ACCESSORIES AND UNPACKING
5.1 Accessories
Depending on the selected controlling behaviour for the central heating system and/or the optional use of a
calorifier, the following items can be supplied with the boiler. Ask your supplier for the specifications.
Item
Part Nº.
Outdoor (air) Temperature Sensor: 12kOhm @ 25°C
E04.016.585
External flow temperature sensor for system side of the low loss header:
10kOhm@25°C
E04.016.304
Calorifier Temperature Sensor: 10kOhm@25°C
E400277
Boiler Circulating Pump for S-CBX 85 & 105
S022.500.011
Boiler Circulating Pump for S-CBX 125
S022.500.012
Boiler Circulating Pump for S-CBX 155
S022.500.013
WIFI module / IP module
S022.500.006
External ignition transformer
S022.500.016
Propane orifice S-CBX 85 & 105
S022.500.001
Propane orifice S-CBX 125
S022.500.004
Propane orifice S-CBX 155
S022.500.010
5.2 Unpacking
The S-CBX boiler will be supplied with the following documents and accessories:
• One “Installation, user and service instructions” manual for the installer.
• One suspension bracket with locking plate and bolts.
• Spare fuses for the boiler control (At the burner controller).
• Spare nuts for mounting the burner plate (in a bag attached to the front of the gas valve).
• Bottom part of the condensate trap.
After delivery, always check the boiler package to see if it is complete and without any defects. Report any
imperfections immediately to your supplier.

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6 INSTALLATION OF THE S-CBX
6.1 Installation Clearances
On all sides of the boiler at least 50 mm of clearance should be applied to walls or wall units, 300 mm above the
top side of the boiler and 250 mm from the bottom/pump of the boiler.
Clearances to wall, ceiling and floor in mm
A: Front
B: Top
C: Sides
D: Back
E: Bottom
Minimum Service Clearances
150
300
50
0
250
Recommended Service clearances
640
350
500
0
750
Clearances from combustible materials 1. Hot water pipes—at least 6 mm from combustible materials.
2. Vent pipe – at least 25 mm from combustible materials.
The installation area/room must have the following provisions:
• 230 V - 50 Hz power source socket with ground.
• Open connection to the sewer system for draining condensing water.
• A wall or stand to properly support the weight of the boiler.
Note: The wall used for mounting the boiler must be able to hold the weight of the boiler. If not, it is recommended
to mount the boiler by means of a (cascade) frame.
6.2 Boiler Installation Location Requirements
Other considerations related to the boiler location.
• The ventilation of the boiler room must meet local and national standards and regulations, regardless of
the selected supply of fresh air to the boiler.
• The flue gas pipes must be connected to the outside wall and/or the outside roof.
• The installation area must be dry and frost-free.
• The boiler has a built-in fan that will generate noise, depending on the total heat demand. The boiler location
should minimize any disturbance this might cause. Preferably mount the boiler on a brick wall.
• There must be sufficient lighting available in the boiler room to work safely on the boiler.
• When a boiler is positioned at the highest point of the installation, the supply and return pipes must first
protrude 0.5 m above the top of the boiler, before these pipes go to the installation side. In other words, the
water level must always be 0.5 meters above the top of the boiler and an automatic air vent must be installed
in the supply or return pipe.
• Remind the positioning of electrical components in relation to the temperature sensitivity.
• Make sure there is an open connection with the sewer to drain the condensate. This connection should be
lower than the condensate drains level of the boiler.
Ceiling
Wall
Pump

17
The boiler must be positioned and installed by a skilled installer in accordance with all applicable standards and
regulations. Commissioning of the boiler must be done by a skilled service/commissioning engineer, who is trained
for this type of boiler.
6.3 Mounting the boiler
Before mounting and installing the boiler the following connections should be considered:
• Flue gas system and the flue gas pipe
connections
• Air supply system and connections
• Flow and return pipe connection
• Condensate and pressure relief valve drainage
• Power supply (preferably the power connection
positioned above the boiler)
• Gas pipe.
All lines/piping must be mounted free of tension. The weight of the installation components should be
supported separately from the boiler so there will be no standing forces on the connections.
This might influence the mounting position of the boiler.
Determine the position of the boiler by using the included suspension bracket or a suspension frame (when
supplied). While marking the holes, ensure that the suspension bracket or frame is perpendicular, and the boiler
does not lean forward. If necessary, adjust the position with the adjusting bolts at the lower rear side of the back
panel (see drawing). When the adjusting bolts aren’t sufficient, fill the gap behind the bolts to get the boiler in
position. The boiler position lies between the boiler hanging level and hanging slightly backwards (min. 0.5° - max
1.5°).
The boiler should not lean forward in the mounted position.
Lock the suspension bracket with
the security cover before making
any other connections to the boiler.
This security cover will prevent the
boiler from falling off the bracket.
Don't use excessive force during
the mounting of the boiler
connections.
3. Lock boiler with locking plate
and two bolts
2. Suspend
boiler with
suspension
bracket on
mounting
bracket
1. Attach mounting bracket to wall
with inclined side facing upwards
4. Level boiler using
adjusting bolts
suspension
detail
Slightly backwards (min. 0.5° - max 1.5°)
for the condensate to properly drain

18
7 CONNECTIONS
7.1 Boiler connections
1 – Flow (Hot water out)
2 – Return (Cold water in)
3 – Gas
4 – Condensate trap cleaning point
5 – Condensate drain
6 – Automatic air vent.
Strain on the gas valve and fittings may result in vibration, premature component failure and leakage and
may result in a fire, explosion, property damage or serious injury. Do not use an open flame to test for gas
leaks. Failure to follow these instructions may result in fire.
7.2 Condensate drain connection
The condensate drain is placed at the centre and at the bottom of
the boiler and has a 19 mm hose discharge. Connect this flexible
hose to the sewer system.
Use only plastic parts with the condensate drain. Metal lines are
not allowed.
Blockage of this drain might damage the boiler. The drain
connection is correct when the condensate can be seen flowing
away, e.g. using a funnel. Any damage that might occur, when the
drain is not installed correctly, is not covered by the warranty of the
boiler.
There should be an open connection of the condensate hose into
the sewage system. A possible vacuum in the sewage system
must never give the opportunity to suck on the boiler’s condensate
drain hose.
When mounting the bottom part of the condensate trap, before commissioning the boiler and/or after
maintenance, the condensate trap must ALWAYS be completely filled with water.
This is a safety measure: the water in the condensate trap keeps the flue gases from leaking
out of the heat exchanger via the condensate drain.
1 2 3 4 5 6
Open connection
to the sewer.

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7.3 Flow and return connections
Use T-pieces for externally mounting the
pressure relief valve and the boiler bleed valve
for servicing the boiler. We advise to install two
service valves in the flow and return pipes
underneath the boiler, so the boiler can be
isolated from the heating system and eventually
disconnected, when needed.
When using a system pump, this pump should
always be mounted in the return pipe of the
heating system.
Do not use chloride-based fluxes for soldering
any pipes of the water system.
7.4 The expansion vessel
The capacity of the expansion vessel must be
selected and based on the capacity of the
central heating system and the static pressure.
Suggested is to fit the expansion vessel in the
return pipe of the central heating system. It can
be combined with the drain valve for service.
See the drawing.
7.5 Pressure relief valve
The boiler has no internal pressure relief valve. This should be installed close to the boiler in the flow pipe of the
heating system. When having cascaded boilers, each boiler should have its own pressure relief valve.
It is recommended to install service valves, so the boiler can be isolated from the heating system, when needed.
Make sure that the pressure relief valve is mounted between the boiler and the service valves.
The specifications and size of the relief valve should be determined by the installer and must comply with all
applicable regulations and boiler capacity.
The condensate trap must
always be filled to the edge
with water, before replacing
to the unit.
Pressure
relief valve
Boiler bleed
valve for service
Boiler
service valves
BOILER
EHS.T0501.100

20
7.6 NON-Return valve.
All S-CBX boilers have a non-return valve installed in the gas-air mixing pipe just before the burner. Flue gas
recirculation is prevented by the non-return valve. The prevention of recirculation also reduces standby losses
through the flue of the boiler. This creates a higher thermal efficiency.
7.7 Bypass
The boiler has no internal bypass. When many thermostatic valves are being used, the system should have a by-
pass to allow an adequate flow when all thermostatic valves are closed. Instead of a bypass also a low-loss header
can be used for this function.
The boiler flow will also be influenced when a pipe of the heating system is frozen / blocked. Make sure all heating
pipes are free from the risk of frost. If there is the risk of freezing of the heating system, all the pipe section must be
insulated and/or protected with the help of a tracing.
7.8 Pump functionality
Delta T monitoring:
A high temperature difference between supply and return of the boiler can indicate a clogged heat exchanger or
filter, or a defective pump. The burner load automatically decreases when the Return/Supply temperature
differential increases too much. See chapter 13 "Temperature protection".
7.9 Frost protection
The boiler has a built-in frost protection that is automatically activating the central heating pump when the boiler
return (water) temperature drops below 10 °C (programmable). When the boiler return temperature drops below 5
°C (programmable), the burner is also ignited. The pump and/or burner will shut down as soon as the return
temperature has reached 15 °C (programmable). The mentioned temperatures are related to the temperatures
measured by the RETURN sensor of the boiler. This frost protection function will not fire up the boiler in case of a
“general blocking” of the burner demand.
NOTICE: This “Frost Protection” function is only useable for the boiler and not for the whole central heating system.
Because it concerns a programmable setting, a boiler damaged by frost is not covered under warranty.