MHG Heating ProCon 16 User manual

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Installation and Operating Manual for the
ProCon 16, 27, 47, 75 & 77
Wall Mounted Condensing Boiler Range.
(RVS 43 Cascade Models)

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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 ProCon HS+ 3
1.5 ProCon HM 3
2.0 Installation Regulations and Requirements 4
2.1 Appliance Warranties. Supplied Components. 5
3.0 Dimensions 16, 27 & 47 6
3.1 Dimensions 75 7
3.2 Dimensions 77 8
3.3 Dimensions Kompact (For Information only) 9
3.4 Installation Clearances and Mounting Information 16, 27 & 47 10
3.5 Installation Clearances and Mounting Information 75 12
3.6 Installation Clearances and Mounting Information 77 14
4.0 Delivery and Mobility 16
4.1 Case Removal 16
5.0 Technical Data 17
6.0 Pressure Relief Valve 18
7.0 Electrical Connections 18
8.0 Hydraulic and Wiring Guide Single Unit Option 1 (Heating Only) (Low Resistance Circuit) 20
8.1 Hydraulic and Wiring Guide Single Unit Option 2 (Heating & HWS) (External 3 Way Valve) 21
8.2 Hydraulic and Wiring Guide Single Unit Option 3 (Heating & HWS) (HS) 22
8.3 Hydraulic and Wiring Guide Single Unit Option 4 (Heating Only) (High Resistance Circuit) 23
8.4 Hydraulic and Wiring Guide Single Unit Option 5 (Heating & HWS) (High Resistance Circuit) 24
8.5 Hydraulic and Wiring Guide Single Unit Option 6 (Heating & HWS) (Two Heating Circuits)(HS) 25
8.6 Hydraulic and Wiring Guide Single Unit Option 7(Heating & HWS) (Two Heating Circuits) 26
8.7 Hydraulic and Wiring Guide Single Unit Option 8 (Heating & HWS) (Two Heating Circuits)(Mixing)(HS) 27
8.8 Hydraulic and Wiring Guide Single Unit Option 9 (Heating & HWS) (Two Heating Circuits)(Mixing) 28
8.9 Hydraulic and Wiring Guide Single Unit Option 10 (Heating & HWS) (Two Heating Circuits)(RVA63) 29
8.10 RVA63 Zone Controller Wiring Information 30
8.11 Hydraulic and Wiring Guide Multiple Units Option 11 (Heating & HWS) (RVS43 Cascade Manager ) 31
8.12 RVS43 Cascade Manager Wiring Information (Controller Only) 32
8.13 RVS43 Cascade Manager Housing Wiring Information (Including Space For RVA46 Zone Controller) 33
8.14 Hydraulic and Wiring Guide Multiple Units Option 12 (Heating & HWS) (RVS43 Cascade Manager+RVA63) 34
9.0 BMS Interface Installation and Parameter Alteration 35
10.0 Fluing Options 36
10.01 MicroMat EC 60-75 Flue Adapter for use with ProCon 77 36
10.1 Single Unit Balanced Flue Wall Termination 37
10.2 Single Unit Balanced Flue Vertical Termination 37
10.3 Single Unit open Flue Wall Termination 37
10.4 Single Unit Open Flue Vertical Termination 38
10.5 Cascaded Open Flue Vertical Termination 38
10.6 Dimensions of Available Flue Components 39
10.7 Balanced Flue Terminal Positions For Boilers below and Above 70kW Net Input 40
11.0 Filling The System 41
11.1 Pressure Vessel 41
12.0 System Water Quality 42
12.1 Care With The Use Of Solder Flux 42
13.0 Appliance Controls 43
13.1 Module Operating Codes 45
14.0 Appliance Fault Codes 46
14.1 Enhanced Appliance Fault Codes 48
15.0 Accessing Boiler Parameters (Control Parameter Default Settings) 49
16.0 RVS43 Cascade Manager General Information 54
16.1 RVS43 Cascade Manager Parameter Setting 60
17.0 Commissioning 92
17.1 Pre-Commissioning Checks. 92
17.2 Combustion System Commissioning 92
17.3 NG/LPG – LPG/NG Conversion Procedure 94
18.0 Routine Inspection and Servicing 95
18.1 Routine Service Inspection 95
18.2 Routine Cleaning and Maintenance 95
19.0 Weather Compensation Slope Graph 96
20.0 Optional System Controls 97
21.0 Internal Wiring Diagrams 98
21.1 Internal Wiring Diagrams 16, 27 & 47 H , HS & S 98
21.2 Internal Wiring Diagrams 47 H & S 99
21.3 Internal Wiring Diagrams 75 & 77 H 100
21.4 Internal Wiring Diagrams 75 & 77 HM 101
22.0 HM and Cascade Slave Units Equipped with OCI420 Communication Clips (LED Indication) 102
23.0 Exploded Spares Diagrams 16, 27 & 47 103
24.0 Exploded Spares Diagrams 75 109
25.0 Exploded Spares Diagrams 77 111
26.0 Installer / End Users Note 114

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1.0 Appliance Type
There are four build 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.
ProCon 16H & 16HS, ProCon 27H, 27S & 27HS, ProCon 47H & 47S, ProCon 75&77H & 75&77HM
1.1 The ProCon H range 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 S range 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 late heat
exchanger.
1.3 The ProCon HS range 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.
1.4 The ProCon HS+ can be supplied complete with an integrated high recovery calorifier for simplified
and attractive installation housed within and extended case. The high recovery calorifer can be located
beneath of adjacent to the boilers. (Further information available via the website
www.mhgheating.co.uk)
1.5 The ProCon HM appliance is supplied complete with and integral RVS43 Cascade Manager capable
of controlling an additional 11 ProCon boilers. Each subsequent boiler must be fitted with an OCI420
Communication Clip.
The product codes for the entire range are:
Product Name Product Code
ProCon 16 H 96.30000-7192
ProCon 16 HS 96.30000-7193
ProCon 27 H 96.30000-7194
ProCon 27 S 96.30000-7195
ProCon 27 HS 96.30000-7196
ProCon 47 H 96.30000-7197
ProCon 47S 96.30000-7198
ProCon 75 H 96.30000-7188
ProCon 75 HM 96.30000-7189
ProCon 77 H 96.30000-7190
ProCon 77 HM 96.30000-7191

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2.0 Installation 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.

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2.1 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.
Supplied Components
All ProCons are supplied with the following components.
QAC 34 Outside Air Sensor. (To activate direct on boiler weather compensation.)
Wall Mounting bracket and fixing kit.
Condensate outlet adapter. (To convert ¾” BPS to 22mm plastic waste.)
Bleed key & heat exchanger venting hose.
Condensate syphon flushing hose. (To be attached to the heat exchanger and flue waste pipes and
flushed with clean water.)

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3.0 Dimensions. 16 – 47 Boilers
Legend
1 Cable Entry Grommets 5 Hot Water Primary Return 22mm (HS Models)
Cold Water Inlet 22mm (S Models)
2 Heating Flow 22mm (All Models)
6 Heating Return 22mm (All Models)
3 Hot Water Primary Flow 22mm (HS Models)
Hot Water Outlet 22mm (S Models) 7 Condensate Outlet ¾” BSP Plastic
4 Gas Inlet 22mm 7.1
Condensate Cleanout Connection ¾” Cap

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3.1 Dimensions.75 Boiler
Legend
A Condensate Cleanout Connection ¾” Cap D Heating Flow 1 ¼”
B Condensate Outlet ¾” BSP Plastic E Gas Supply inlet ¾”
C Heating Return 1 ¼” F Cable Entry Grommets

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3.2 Dimensions. 77 Boiler
Legend
1 Heating Return Connection 1 ¼” 4 Condensate Cleanout Connection ¾” Cap
2 Heating Flow Connection Option 1 ¼” 5 Gas Inlet ¾”
3 Condensate Outlet ¾” BSP Plastic 6 Cable Entry Grommets
**Please note that the flexible flow connection can be rerouted to the top of the boiler if required.**

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3.3 Dimensions HS + Calorifier Below (Additional information available from the website www.mhgheating.co.uk)
Legend
VL Hot water Primary Flow 1” RL
Hot Water Primary Return 1”
WW Hot Water Secondary Outlet ¾” A 120 Litre Calorifier
Z Hot Water Secondary Return ½” B Pipework Cover
KW Cold Water Secondary Inlet ¾” C Calorifier Cover
3.3 Dimensions HS + Calorifier Adjacent (Additional information available from the website www.mhgheating.co.uk)
Legend
RL Hot Water Primary Return ¾” VL
Hot water Primary Flow ¾”
WW Hot Water Secondary Outlet ¾” D 60 Litre Calorifier
KW Cold Water Secondary Inlet ¾” E Calorifier Cover
Z Hot Water Secondary Return ½” F Pipework Cover

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3.4 Installation and Service Clearances 16-47 Boilers

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3.4 Mounting Information 16 – 47 Boilers

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3.5 Installation and Service Clearances 75 Boiler

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3.5 Mounting Clearances 75 Boiler

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3.6 Installation and Service Clearances 77 Boiler

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3.6 Mounting Clearances 77 Boiler

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4.0 Delivery 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.
4.1 Case 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 all greater access to all internal
components.
The lower case is secured on either side by thumb nuts located on the return edge on the side case.

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5.0 Technical Data
Technical Data Units 16 H &
HS
27 H &
HS & (S)
47 H &
(S)
75 & 77
H & HM
Nominal Heat Input Net Min/Max kW 4.0/15.0 6.5/25.0 12.0/45.0 15.0/70.0
Nominal Heat Input Gross Min/Max kW 4.4/16.5 7.2/27.5 13.2/49.5 16.5/77.0
Carbon Emissions
100% Of max Output
G20
G31
kgC/kWhr
kgC/kWhr
0.061
0.078
0.061
0.078
0.061
0.078
0.060
0.077
Carbon Emissions
30% Of max Output
G20
G31
kgC/kWhr
kgC/kWhr
0.055
0.070
0.055
0.070
0.055
0.070
0.055
0.070
SEDBUK Rating B B B B
Operating Efficiency (40ºC/30ºC) % 108.8 108.7 108.5 108.5
Nominal Heat Output (50ºC/30ºC)
Min/Max kW 4.3/15.8 7.0/26.2 12.9/47.0 16.0/74.6
Design Flow Rate (50ºC/30ºC) Ltr/sec 0.188 0.312 0.560 0.880
Nominal Heat Output (80ºC/60ºC)
Min/Max kW 3.7/14.5 6.3/24.2 11.7/43.5 14.5/67.8
Design Flow Rate (80ºC/60ºC) Ltr/sec 0.172 0.288 0.519 0.807
Hot Water Generation Output kW (31.3) (45)
Hot water flow rate @ DT 30)C Ltr/min (15) (20)
Min Flow Rate For H/W Activation Ltr/min (3) (3)
Maximum Secondary Water
Pressure bar (10) (10)
Minimum Flow Rate Ltr/sec 0.125 0.246 0.373 0.592
Residual Head from In-built Pump m/W.C 3.7 1.3 0.5 0.75
Maximum Input Gas Rate G20
G31
m³/hr
m³/hr
1.55
0.57
2.55
1.00
4.65
1.72
6.91
2.60
Gas Inlet Pressure Min/Max Mbar 18.0/50.0 18.0/50.0 18.0/50.0 18.0/50.0
Maximum Flue Gas Volume (Hot) m³/hr 21.36 40.81 64.08 96.84
Available Fan Pressure Pa 400 400 400 400
Maximum Water Pressure (Hot) bar 3.0 3.0 3.0 3.0
Minimum Water Pressure (Cold) bar 0.8 0.8 0.8 0.8
Maximum Flow Temperature ºC 90 90 90 90
Power Supply (230 V / 50 Hz) Amps 5 5 5 5
Max Power Consumption Watts 122 129 145 250
Water Content Ltrs 4 5.2 5.2 8.2
Lift Weight (Dry) kg 43.0 43.0 43.0 70.0
Flue Connection
Flue Gas Outlet Female 80mm 80mm 80mm 80mm
Combustion Air Inlet Male 125mm 125mm 125mm 125mm
Concentrically Configured
(Straight or Elbow Adapter Required.) Yes Yes Yes Yes

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6.0 Pressure (Safety) Relief Valve
In accordance with the prevailing British Standard 5440/6644, the installer shall install as suitably sized
Pressure (Safety) Relief Valve.
The location of this valve is important with respect to the applied pressure of the boiler circulation
pump, it is therefore recommended to locate the Pressure (Safety) Relief Valve on the flow pipe
immediately adjacent to the boiler; furthermore, there must not be any means of isolation between
the boiler and the Pressure (Safety) Relief Valve.
7.0 Electrical Connections
Basic electrical connection for all types of ProCon
Legend
Low Voltage Control terminals < 25 Volts
RU 1 QAA73 Room Unit Not Polarity Sensitive < 24Volts
(Link terminals to activate second heating zone control.)
2
RT 3 Heating Circuit 1 Volt Free Enable Not Polarity Sensitive (Room stat/BMS) < 24 Volts
4
AT 5 Outside Air Sensor (QAC34) Not Polarity Sensitive < 24Volts
(Required to Activate Direct on Boiler Weather Compensation)
6
BW 7 Hot Water Sensor (QAZ36) or Hot Water Volt Free Enable (Thermostat/BMS).
Not Polarity Sensitive < 24Volts
8
High Voltage Output and Input Terminals 230 Volts
E 9 Common Earth Terminal
BW/K3
10 Permanent 230 Volt Output for Motor Open Motor Close Hot Water Diverter Valve
11 Neutral Terminal for Hot Water Diverter Valve or Charging Pump
12 230 Volt Output For Hot Water Diverter Valve or Charging Pump (Max 1Amp)
K2 13 230 Volt Output For Heating Circuit Pump (ProCon 16-27)/Boiler Pump ProCon 47, 75&77) (Max 1Amp)
14 Neutral Terminal for heating/Boiler Pump
E 15 Common Earth Terminal
K1 16 Neutral Terminal for heating/Boiler Pump
17 230 Volt Output For Boiler Pump (ProCon 16-27)/Heating Circuit Pump ProCon 47,75&77) (Max 1Amp)
E 18 Permanent Earth Terminal
N 19 Switched Fused Permanent Neutral
L 20 Switched Fused Permanent 230 Volt Live (Max 5Amp)

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Enhanced electrical connection for ProCon HM (Units supplied with an integral Cascade manager)
Legend
High Voltage Output Terminals 230 Volts
BW
N Neutral Terminal for Hot Water Charging Pump
E Earth Terminal for Hot Water Charging Pump
L 230 Volt Output For Hot Water Charging Pump (Max 1Amp)
HK/ZB
N Neutral Terminal for Heating Circuit Pump
E Earth Terminal for heating Circuit Pump
L 230 Volt Output For Heating Circuit Pump (Max 1Amp)
Low Voltage Control terminals < 25 Volts
H1 M H1 Ground Terminal
H1 Controller Operating Input (Volt free Enable/0-10 Volt Control/Mode Alteration)
RL M System Return Sensor (QAD 36) Terminal Not Polarity Sensitive < 25 Volts
B70/B4
VL M System Flow Sensor (QAD 36) Terminal Not Polarity Sensitive < 25 Volts
B10
BW M Hot Water Sensor (QAZ36) or Hot Water Volt Free Enable (Thermostat/BMS).
Not Polarity Sensitive < 24Volts
B3
AF M Outside Air Sensor (QAC34) or (3000ΩSubstitute Resistor = -10C) Not Polarity Sensitive < 24Volts
(Required to Activate Direct On Boiler Weather Compensation)
B9
RU
MD Cascade Controller Output to Slave Boilers. Polarity Sensitive (Screened Cable Required)
(X41 Terminal 2 (Right) OCI420 Communication Clip)
A6 Cascade Controller Output to Slave Boilers. Polarity Sensitive (Screened Cable Required)
(X41 Terminal 1 (Left) OCI420 Communication Clip)
Please note that two outside air sensors are available. Please ensure that the units are wired as follows.
QAC34
Wired to the either AT terminals.
In either case the outside air temperature will be communicated to all controllers.

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8.0 Hydraulic Design Single Unit (Option 1)
Electrical Connections Single Unit (Option 1)
Parameter # Parameters Description Default Proposed Change
H554 b3 Weather Compensation (1) / Constant Flow Temperature Operation
(0)
(E10 Error signal when outside air sensor is not installed.)
1 0