MHG Heating ProCon E 26 User manual

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Installation and Operating Manual for the
ProCon E 26
Wall Mounted Condensing Boiler Range

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Section
Page #
1.0
Appliance Type
3
1.1
ProCon H
3
1.2
ProCon S
3
1.3
ProCon HS
3
1.4
Supplied Components
3
2.0
Pressure Relief Valve
3
3.0
Installation Regulations and Requirements
4
3.1
Appliance Warranties. Supplied Components.
4
4.0
Dimensions
5
4.1
Installation Clearances
6
4.2
Mounting Information
7
5.0
Delivery and Mobility
7
5.1
Case Removal
7
6.0
Technical Data
8
7.0
Electrical Connections
9-10
7.1
Internal Wiring Diagram
11
8.0
Hydraulic and Wiring Guide Single Unit Option 1 (Heating Only)
12
8.1
Hydraulic and Wiring Guide Single Unit Option 2 (Heating Only)
13
8.2
Hydraulic and Wiring Guide Single Unit Option 3 (Heating & HWS)
14
8.3
Hydraulic and Wiring Guide Single Unit Option 4 (Heating Only) ) (External 3 Way Valve)
15
8.4
Hydraulic and Wiring Guide Single Unit Option 5 (Heating & HWS) (Combi)
16
8.5
Hydraulic and Wiring Guide Single Unit Option 6 (Heating & HWS) ) (Internal 3 Way Valve)
17
8.6
Hydraulic and Wiring Guide Single Unit Option 7(Heating & HWS) (Two Heating Circuits)(HC2
External 3 Way Valve)
18
8.7
Hydraulic and Wiring Guide two boiler Cascade Option 8 (Heating & HWS) (Two Heating
Circuits)(HC2 External 3 Way Valve)
19
9.0
Fluing Options
20
9.1
Single Unit Balanced Flue Wall Termination
21
9.2
Single Unit Balanced Flue Vertical Termination
21
9.3
Single Unit Balanced Flue with Concentric to Twin DN80 Products of Combustion and
Combustion Air Ducts.
21
9.4
Single Unit open Flue Wall Termination
22
9.5
Single Unit Open Flue Vertical Termination
22
9.6
Cascaded Open Flue Vertical Termination
22
9.7
Dimensions of Available Flue Components
23
9.8
Balanced Flue Terminal Positions For Boilers below and Above 70kW Net Input
24
10.0
Appliance Controls
25
10.1
Accessing Boiler Parameters (Control Parameter Default Settings)
26-60
10.2
Weather Compensation Slope Graph
61
10.3
Appliance Fault Codes Including Enhanced Fault Codes
61-63
11.0
Filling The System
64
11.1
Pressure Vessel
64
12.0
System Water Quality
65
12.1
Care With The Use Of Solder Flux
65
13.0
Commissioning
66
13.1
Pre-Commissioning Checks
66
13.2
Combustion System Commissioning
66
13.3
NG/LPG –LPG/NG Conversion Procedure
67
14.0
Routine Inspection and Servicing
67
14.1
Routine Service Inspection Routine Cleaning and Maintenance
67-68
15.0
Exploded Spares Diagrams
69-72
Notes
73

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1.0 Appliance TypeThere arethreebuild types and four outputs within the ProCon range.
Please ensure you have the correct unit for the application and where required located correctly within the
cascade prior to beginning the installation.
1.1 The ProCon HRange of appliances is designed to be applied to systems requiring direct on boiler
weather compensated heating and priority hot water production via a separate high recovery
calorifier/cylinder.
1.2 The ProCon SRange of appliances is designed to be applied to systems requiring direct on boiler
weather compensated heating and priority on demand hot water production via an internal plate heat
exchanger.
1.3 The ProCon HSRange of appliances are designed to be applied to systems requiring direct on boiler
weather compensated heating and priority hot water production via a separate high recovery
calorifier/cylinder, where the diverter valve controlling the production of hot water is within the boiler case.
1.4Supplied Components
All ProCon boilers are supplied with the following components.
QAC 34 Outside Air Sensor (To activate direct on boiler weather compensation)
Wall Mounting bracket and fixing kit.
2.0 Pressure (Safety) Relief Valve
In accordance with the prevailing British Standard 5440/6644, the installer shall install and additionally
required suitably sized Pressure (Safety) Relief Valve. In addition to the one fitted within the boiler.
The location of this valve is important with respect to the applied pressure of the circulation pumps, it is
therefore recommended to locate the Pressure (Safety) Relief Valve on the flow pipe immediately adjacent
to any heat source; furthermore, there must not be any means of isolation between the heat source and the
Pressure (Safety) Relief Valve.

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3.0Installation Regulations and Requirements
The installation of ProCon HT boilers must be in accordance with the relevant requirements of Gas Safety
(Installation & Use) Regulations 1994, Health & Safety at Work Act, Building Regulations, IEE Regulations,
Construction (Design & Management) Regulations 1994, Local Authority Bye-Laws, National, Fire
Regulations and Insurance Company requirements.
The following Codes of Practice are also applicable:-
BS 5440-1: 2000 Installation of flues and ventilation for gas appliances of rated input not exceeding 70 kW
net (1st, 2nd and 3rd family gases).
Part 1: Specification for the installation of flues.
BS 5440-2: 2000 Installation of flues and ventilation for gas appliances of rated input not exceeding 70 kW
net (1st, 2nd and 3rd family gases).
Part 2: Specification for installation and maintenance of ventilation for gas appliances.
BS 5449: 1990 Specification for forced circulation hot water central heating systems for domestic premises.
BS 6644: 2005 Specification for gas fired hot water boilers of rated inputs between 70kW (net) and
1.8MW(net) (2nd and 3rd family gases).
BS 6798: 1987 Specification for installation of gas fired hot water boilers of rated input not exceeding 60 kW.
BS 6880: 1988 Code of Practice for low temperature hot water heating systems of output greater than
45kW.Parts 1, 2 & 3.
BS 6891: 1988 Specification for installation of low pressure gas pipework of up to 28mm (R1) in domestic
premises (2nd family gases)
BS 7593: 1992 Code of Practice for treatment of water in domestic hot water central heating systems.
BS 7671: 1992 Requirements for electrical installations.IEE Wiring Regulations.Sixteenth edition.
CISBE Guide reference sections B7, B11 and B13.
CP342 Part 2: 1974 Code of Practice for centralized hot water supply.
GE/UP/2 Gas installation pipework, boosters and compressors on industrial and commercial premises.
IGE/UP/4 Commissioning of gas fired plant on industrial and commercial premises
IGE/UP/10 Installation of gas appliances in industrial and commercial premises. Part 1: Flued appliances.
And any addition prevailing regulation and or code of practice not detailed above.
3.1 Appliance Warranties
All MHG appliances enjoy a full 24 month warranty as detailed in our terms and conditions.
The guarantee period shall begin on the day of commissioning, or at latest 3 months after delivery has been
made.
The customer shall only be able to claim against MHG under guarantee if the commissioning of the object of
delivery has been carried out by MHG staff or the authorised supplier, if the customer has followed MHG's
instructions relating to the treatment and maintenance of the object of delivery, and if no replacement parts
of outside origin have been fitted.
Parts subject to wear such as ignition electrodes, seals etc. are strictly excluded from the guarantee.”
In addition to the above warranties, the Primary Heat Exchangers carry a 60 month guarantee against
manufacturing or material defect.

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4.0Dimensions
1
Cable Entry Grommets
6
*Heating Return ¾” (All Models)
2
Heating Flow ¾” (All Models)
7
Condensate Outlet ¾” BSP Plastic
3
*Hot Water Primary Flow ½” (HS Models)
*Hot Water Outlet ½” (S Models)
8
Condensate Cleanout Connection ¾” Cap
4
*Gas Inlet ¾
9
Pressure Relief Valve outlet
5
*Hot Water Primary Return ½”(HS Models)
*Cold Water Inlet ½”(S Models)
*External thread, flat sealing

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4.1Installation and Service Clearances
A clearance of 600mm is required in front of the appliance for servicing.

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4.2 Mounting Information
Attach the wall rail with the enclosed fastening set.
The mounting set consists of:
2 PCs. Hexagon Woodscrew 8 x 65 DIN 571, SW13
2 PCs. Wall plugs S10
2 PCs. washers 8.4 DIN 125, steel A3B
5.0Delivery and Mobility
All ProCons are supplied fully tested and therefore may contain residual test water.
The test water utilised contains additives that will help prevent the pump from sticking and other metals from
oxidising.
To maintain the structural integrity of the appliance the internal components should not be used during the
lifting and positioning of the unit onto the wall bracket.
All packaging materials should be disposed of in an environmentally way.
5.1Case Removal
To remove the case insert a flat blade screwdriver or similar into the black latch slots and turn through 900.
Pull the base of the cover forward and up to release the hooks at the top. Ensure that the earth cable is
removed prior to lifting the cover clear.
The lower case housing the display panel can be hinged down to allow greater access to all internal
components.
The lower case is secured on either side by screws located on the front edge of the case.

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6.0 Technical Data
Technical Data
Units
H
HS
S
Product Identification Number
CE-0085CO0278
Category
II2ELL3P(DE), II2H3P(AP,ES,IE,IT,PT)
Volume of Water in Boiler
L
2.8
Weight of Boiler (Including Packaging)
Kg
38.4 (45)
38.6 (45)
39 (46.2)
Dimensions (H x W x D)
mm
750X440X437
Heating Flow and Return Connections
¾” External Thread, Flat Sealing
Hot water flow and return (Mains Inlet)
½” External Thread, Flat Sealing
Gas Connection
¾” External Thread, Flat Sealing
Flue Size
DN 80/125
Condensate Drain
¾”
Nominal Heat Input
kW
2.9-24.9
Nominal Heat Output 80/60°C
kW
2.7-24.1
Nominal Heat Output 50/30°C
kW
3.3-26.0
Efficiency 40/30°C
%
108.2
Gas Types
Nat. Gas
LPG
Gas Air Mixing Valve Opening
Mm
30
26.1
CO2-Min Load
Vol.%
9.3
10.5
CO2-Max Load
Vol.%
8.7
10.3
Exhaust Temperature at 80/60°C min.Load
°C
68
Exhaust Temperature at 80/60°C max.Load
°C
78
Max. Poss. Delivery Pressure at Flue Outlet
Pa
200
Flue Types
B23, B23p, B33, C13x, C33x, C43x, C63x, C93x
Min. Gas Supply Pressure
Mbar
18.0
30.0
Max. Gas Supply Pressure
Mbar
25.0
50.0
Max. Gas Supply Pressure, Pimax
Mbar
60
Gas Power Consumption for Natural Gas
H (HU = 10.0 kWh / m3)
m3/h
2.5
Electrical Connection
230V 1/N/PE ~ 50Hz
Max. Electrical Power Consumption
W
98
Min Flow Rate
l/h
120
Delivery at ∆t = 20°C
l/h
1070
Max. Flow Temperature
°C
90
Max. Operating working Pressure
Bar
3
DHW
Max. Water Pressure
Bar
10
Max. Permissible Water Hardness
mol/m3
2.7*
DHW Continuous Output with ∆t = 30K
l/min
11.5
Max. DHW Nominal Power
kW
24.1
Min. Draw-off Rate
l/min
3
Drinking Water Connection
G
½
Water Content
L
0.5
*(Corresponds to 15° dH or 27° fH,19° E)

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7.0 Electrical Connections
Basic electrical connection for all types of ProCon E
30
H1 Programmable Input
Orange/White
31
H1 Sensor Ground
Black
32
H4 Programmable Input
Green
33
H4 & H5 Sensor Ground
Black
34
H5 Programmable Input
White
35
CL+ QAA75/78 Room Unit
Blue
36
CL- QAA75/78 Room Unit
Green
37
G+ QAA75/78 Room Unit
Red
20
B9 Outside Air Sensor (QAC34)
Yellow
21
B9 & B3 Sensor Ground
Black
22
B3 HWS Sensor / Volt Free Enable
Red
23
BX3 Programmable Sensor Input
Brown/White
24
BX2/BX3 Sensor Ground
Black
25
BX2 Programmable Senor Input
Grey
26
BX21 Sensor Ground
Black
27
BX21 Programmable Input (AGU Clip)
White
28
MB LPB Cascade Communication (OCI Clip)
Black/Green
29
DB LPB Cascade Communication (OCI Clip)
Brown

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10
*QX3 Live 3 Way Valve Close Programmable Output (Red)
Violet
11
*QX3 Live HWS Pump or 3 way Valve Open Programmable
Output (White)
Pink
12
QX3/QX1 Neutral (Black)
Blue
13
QX3/QX1Earth
Green/Yellow
14
*QX1 Live Heating Circuit 1 Pump Programmable Output
Grey
15
*QX23 Live Programmable Output (AGU Clip)
Orange
16
QX23 Neutral Programmable Output (AGU Clip)
Blue
17
QX23 Earth Programmable Output (AGU Clip)
Green/Yellow
18
*QX22 Live Programmable Output (AGU Clip)
Red
19
*QX21 Live Programmable Output (AGU Clip)
Black
*Max switching capability 0.5 Amps
N
Permanent Neutral
Blue
E
Permanent Earth
Green/Yellow
L
Permanent Live 5Amp
Brown
4
Internal Boiler Pump Neutral
Blue
5
Internal Boiler Pump Earth
Green/Yellow
6
Internal Boiler Pump Live
Brown
7
QX2 Neutral Programmable Output
Blue
8
QX2 Earth Programmable Output
Green/Yellow
9
*QX2 Live Programmable Output
Brown
*Max switching capability 0.5 Amps

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7.1 Internal wiring diagram
Key
Colour
bl
Blue
br
Brown
br/ws
Brown/White
gb
Yellow
gn
Green
gn/gb
Green/Yellow
gr
Grey
or
Orange
rs
Pink
rt
Red
sw
Black
vi
Violet
ws
White
ws/rt
White/Red

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8.0 Hydraulic Design Single Unit (Option 1) (New Installations only)
Electrical Connections Single Unit (Option 1)
Terminal
Description
N
Permanent Neutral
E
Permanent Earth
L
Permanent Live 5Amp
20
B9 Outside Air Sensor (QAC34)
21
B9 & B3 Sensor Ground
33
H5 Ground
34
H5 Room thermostat VF or 0-10V
35
CL+ QAA75/78 Room Unit (if used)
36
CL- QAA75/78 Room Unit (if used)
37
G+ QAA75/78 Room Unit (if used)

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8.1Hydraulic Design Single Unit (Option 2)
Electrical Connections Single Unit (Option 2)
Terminal
Description
Terminal
Description
N
Permanent Neutral
20
B9 Outside Air Sensor (QAC34)
E
Permanent Earth
21
B9 & B3 Sensor Ground
L
Permanent Live 5Amp
33
H5 Ground
12
QX3/QX1 Neutral
34
H5 Room thermostat VF or 0-10V
13
QX3/QX1Earth
35
CL+ QAA75/78 Room Unit (if used)
14
*QX1 Live Heating Circuit 1 Pump
36
CL- QAA75/78 Room Unit (if used)
37
G+ QAA75/78 Room Unit (if used)
*Max switching capability 0.5 Amps

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8.2Hydraulic Design Single Unit (Option 3)
Electrical Connections Single Unit (Option 3)
Terminal
Description
Terminal
Description
N
Permanent Neutral
20
B9 Outside Air Sensor (QAC34)
E
Permanent Earth
21
B9 & B3 Sensor Ground
L
Permanent Live 5Amp
22
B3 DHW sensor / Volt Free Enable
11
*QX3 Live DHW Pump
33
H5 Ground
12
QX3/QX1 Neutral
34
H5 Room thermostat VF or 0-10V
13
QX3/QX1Earth
35
CL+ QAA75/78 Room Unit (if used)
14
*QX1 Live Heating Circuit 1 Pump
36
CL- QAA75/78 Room Unit (if used)
37
G+ QAA75/78 Room Unit (if used)
*Max switching capability 0.5 Amps

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8.3Hydraulic Design Single Unit (Option 4)
Electrical Connections Single Unit (Option 4)
Terminal
Description
Terminal
Description
N
Permanent Neutral
20
B9 Outside Air Sensor (QAC34)
E
Permanent Earth
21
B9 & B3 Sensor Ground
L
Permanent Live 5Amp
26
BX21 Sensor Ground
15
*QX23 Live Circuit 1 Heating pump
27
BX21 Flow Sensor Heating Circuit 1
16
QX23 Neutral Circuit 1 Heating pump
33
H5 Ground
17
QX23 Earth Circuit 1 Heating pump
34
H5 Room thermostat VF or 0-10V
18
*QX22 Live 3 Way Valve Close
35
CL+ QAA75/78 Room Unit (if used)
19
*QX21 Live 3 Way Valve Open
36
CL- QAA75/78 Room Unit (if used)
37
G+ QAA75/78 Room Unit (if used)
*Max switching capability 0.5 Amps
Parameter #
Parameters Description
Default
Proposed
Change
6020
Function Extension module 1
Heating Circuit 2
Heating Circuit 1

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8.4Hydraulic Design Single Unit (Option 5)
Electrical Connections Single Unit (Option 5)
Terminal
Description
Terminal
Description
N
Permanent Neutral
20
B9 Outside Air Sensor (QAC34)
E
Permanent Earth
21
B9 & B3 Sensor Ground
L
Permanent Live 5Amp
33
H5 Ground
12
QX1 Neutral Circuit 1 Heating Pump
34
H5 Room thermostat VF or 0-10V
13
QX1 Earth Circuit 1 Heating Pump
35
CL+ QAA75/78 Room Unit (if used)
14
*QX1 Live Circuit 1 Heating Pump
36
CL- QAA75/78 Room Unit (if used)
37
G+ QAA75/78 Room Unit (if used)
*Max switching capability 0.5 Amps

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8.5Hydraulic Design Single Unit (Option 6)
Electrical Connections Single Unit (Option 6)
Terminal
Description
Terminal
Description
N
Permanent Neutral
20
B9 Outside Air Sensor (QAC34)
E
Permanent Earth
21
B9 & B3 Sensor Ground
L
Permanent Live 5Amp
22
B3 DHW sensor / Volt Free Enable
10
*QX3 Live 3 Way Valve Close
Programmable Output (Red)
33
H5 Ground
11
*QX3 Live HWS Pump or 3 way
Valve Open Programmable Output
(White)
34
H5 Room thermostat VF or 0-10V
12
QX3 (Black)/QX1 Neutral Heating
Circuit 1 Pump
35
CL+ QAA75/78 Room Unit (if used)
13
QX1Earth Heating Circuit 1 Pump
36
CL- QAA75/78 Room Unit (if used)
14
*QX1 Live Heating Circuit 1 Pump
37
G+ QAA75/78 Room Unit (if used)
*Max switching capability 0.5 Amps

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8.6Hydraulic Design Single Unit (Option 7)
Electrical Connections Single Unit (Option 7)
Max switching capability 0.5 Amps
Parameter #
Parameters Description
Default
Proposed
Change
6020
Function Extension module 1
Heating Circuit 2
Heating Circuit 1
Terminal
Description
Terminal
Description
N
Permanent Neutral
20
B9 Outside Air Sensor (QAC34)
E
Permanent Earth
21
B9 & B3 Sensor Ground
L
Permanent Live 5Amp
22
B3 DHW sensor / Volt Free Enable
12
QX1 Neutral Heating Circuit 1 Pump
26
BX21 Sensor Ground
13
QX1 Earth Heating Circuit 1 Pump
27
BX21 Flow Sensor Heating Circuit 2
14
*QX1 Live Heating Circuit 1 Pump
33
H5 Ground
15
*QX23 Live Circuit 2 Heating pump
34
H5 Room thermostat VF or 0-10V
16
QX23 Neutral Circuit 2 Heating pump
32
H4 HC2 Room Thermostat VF or 0-10V
17
QX23 Earth Circuit 2 Heating pump
33
H4 Ground
18
*QX22 Live HC2 3 Way Valve Close
35
CL+ QAA75/78 Room Unit (if used)
19
*QX21 Live HC2 3 Way Valve Open
36
CL- QAA75/78 Room Unit (if used)
37
G+ QAA75/78 Room Unit (if used)

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8.7Hydraulic Design Single Unit (Option 8)
Electrical Connections Single Unit (Option 8)
Master Boiler
Terminal
Description
Terminal
Description
N
Permanent Neutral
21
B9 & B3 Sensor Ground
E
Permanent Earth
22
B3 DHW sensor / Volt Free Enable
L
Permanent Live 5Amp
26
BX21 Sensor Ground
12
QX1 Neutral Heating Circuit 1 Pump
27
BX21 Flow Sensor Heating Circuit 2
13
QX1 Earth Heating Circuit 1 Pump
28
MB LPB Cascade Communication
14
*QX1 Live Heating Circuit 1 Pump
29
DB LPB Cascade Communication
15
*QX23 Live Circuit 2 Heating pump
33
H5 Ground
16
QX23 Neutral Circuit 2 Heating pump
34
H5 Room thermostat VF or 0-10V
17
QX23 Earth Circuit 2 Heating pump
32
H4 HC2 Room Thermostat VF or 0-10V
18
*QX22 Live HC2 3 Way Valve Close
33
H4 Ground
19
*QX21 Live HC2 3 Way Valve Open
35
CL+ QAA75/78 Room Unit (if used)
20
B9 Outside Air Sensor (QAC34)
36
CL- QAA75/78 Room Unit (if used)
37
G+ QAA75/78 Room Unit (if used)
Max switching capability 0.5 Amps
Slave Boiler/Boilers
Terminal
Description
Terminal
Description
N
Permanent Neutral
28
MB LPB Cascade Communication
E
Permanent Earth
29
DB LPB Cascade Communication
L
Permanent Live 5Amp

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20
MHG Heating Ltd Unit 4 Epsom Downs Metro Centre, Waterfield, Tadworth, Surrey KT20 5LR
Telephone [phone] Fax [phone] Email [e-mail] Web www.mhgheating.co.uk
140116
9.0 Fluing Options
Please note that excessive resistance within the flue and combustion air supply systems will lead to a
reduction in the output of the appliance and induce operational faults.
80/125mm Concentric Flue Components (Pa Resistances)
Wall Terminal
5.0
Vertical Terminal
5.0
955mm Flue Extension
4.0
500mm Flue Extension
2.0
255mm Flue Extension
1.5
87º Bend
4.0
45º Bend
2.0
30º Bend
1.5
80mmØ PPS Flue Components (Pa Resistances)
Exhaust Pipe Terminal
2.5
Air Pipe Terminal
4.0
955mm Flue Extension
3.0
500mm Flue Extension
1.5
255mm Flue Extension
1.0
87º Bend
3.0
45º Bend
1.5
30º Bend
1.0
When flues are installed with horizontal sections/portions a 30fall back to the boiler must be maintained. This
will not only ensure condensate removal preventing premature seal failure, but also prevent nuisances
dripping from the wall terminal.
Dimensions below are for concentric DN80/125 boiler connector fittings.