Lochinvar Mini Copper-Fin MCW91CE Guide

The Mini Copper-Fin® range
High Efficiency Gas Fired Water Heaters and
Boilers
Installation, Commissioning and
Maintenance Instructions
Models:
MCW91CE
MCW136CE
MCW181CE
MCW226CE
MCW271CE
MCW316CE
MCW361CE
MCW401CE
MCW501CE
MCB91CE
MCB136CE
MCB181CE
MCB226CE
MCB271CE
MCB316CE
MCB361CE
MCB401CE
MCB501CE
INS0023 Issue No 6 | August 2011

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Table of Contents
1.0 INTRODUCTION......................................................................................................................................................................................................................................4
2.0 PRINCIPAL PARTS.................................................................................................................................................................................................................................5
3.0 TECHNICAL DATA..................................................................................................................................................................................................................................7
4.0 GENERAL REQUIREMENTS..................................................................................................................................................................................................................9
4.1 RELATED DOCUMENTS.................................................................................................................................................................................................................9
5.0 WATER QUALITY..................................................................................................................................................................................................................................10
6.0 LOCATION.............................................................................................................................................................................................................................................10
6.1 PLANT ROOM VENTILATION .......................................................................................................................................................................................................10
6.2 GENERAL REQUIREMENTS.........................................................................................................................................................................................................10
6.3 CLEARANCES................................................................................................................................................................................................................................10
7.0 GAS SUPPLY.........................................................................................................................................................................................................................................11
7.1 SERVICE PIPES.............................................................................................................................................................................................................................11
7.2 METERS..........................................................................................................................................................................................................................................11
7.3 GAS SUPPLY PIPES......................................................................................................................................................................................................................11
7.4 BOOSTED SUPPLIES....................................................................................................................................................................................................................11
7.5 PLANT-ROOM CONTROL VALVE ................................................................................................................................................................................................11
7.6 EQUIPMENT GAS SYSTEM LEAK CHECK..................................................................................................................................................................................11
8.0 FLUE SYSTEM.......................................................................................................................................................................................................................................12
8.1 FLUE SYSTEM GENERAL REQUIREMENTS..............................................................................................................................................................................12
8.2 FLUE SYSTEMS.............................................................................................................................................................................................................................12
8.3 FLUE MATERIALS – CONVENTIONAL FLUE INSTALLATIONS ................................................................................................................................................12
8.4 MULTIPLE FLUE INSTALLATION.................................................................................................................................................................................................13
8.5 FAN DILUTION SYSTEMS.............................................................................................................................................................................................................13
8.6 BALANCED COMPARTMENTS.....................................................................................................................................................................................................13
9.0 AIR SUPPLY ..........................................................................................................................................................................................................................................13
9.1 NATURAL VENTILATION...............................................................................................................................................................................................................13
9.2 MECHANICAL VENTILATION........................................................................................................................................................................................................14
10.0 WATER CONNECTIONS.......................................................................................................................................................................................................................16
10.1 WATER HEATERS.........................................................................................................................................................................................................................16
10.1.1 GENERAL........................................................................................................................................................................................................................16
10.1.2 OPEN VENTED SYSTEM ARRANGEMENT.................................................................................................................................................................16
10.1.3 UNVENTED SYSTEM ARRANGEMENT .......................................................................................................................................................................16
10.1.4 WATER PRESSURE GAUGE.........................................................................................................................................................................................16
10.1.5 DRAIN VALVES...............................................................................................................................................................................................................16
10.1.6 EXPANSION VESSEL SIZING .......................................................................................................................................................................................17
10.1.7 DE-STRATIFICATION.....................................................................................................................................................................................................17
10.1.8 CIRCULATING PUMPS ..................................................................................................................................................................................................17
10.1.9 PIPEWORK SIZE............................................................................................................................................................................................................18
10.2 HEATING BOILERS........................................................................................................................................................................................................................19
10.2.1 GENERAL........................................................................................................................................................................................................................19
10.2.2 OPEN VENTED SYSTEM ARRANGEMENT.................................................................................................................................................................19
10.2.3 SEALED SYSTEM ARRANGEMENT.............................................................................................................................................................................19
10.2.4 DRAIN VALVES...............................................................................................................................................................................................................19
10.2.5 EXPANSION VESSEL SIZING .......................................................................................................................................................................................20
10.2.6 PRIMARY CIRCULATING PUMPS.................................................................................................................................................................................20
10.3 POOL HEATING.............................................................................................................................................................................................................................21
10.4 FLOW SWITCH...............................................................................................................................................................................................................................21
11.0 ELECTRICAL SUPPLY .........................................................................................................................................................................................................................21
11.1 ELECTRICAL CONNECTIONS......................................................................................................................................................................................................22
11.2 EXTERNAL CONTROLS................................................................................................................................................................................................................22
11.3 ARC WELDING PRECAUTIONS ...................................................................................................................................................................................................22
11.4 WIRING DIAGRAM.........................................................................................................................................................................................................................23
12.0 COMMISSIONING AND TESTING........................................................................................................................................................................................................25
12.1 ELECTRICAL INSTALLATION.......................................................................................................................................................................................................25
12.2 GAS INSTALLATION......................................................................................................................................................................................................................25
12.3 WATER CONNECTIONS ...............................................................................................................................................................................................................25
12.4 COMMISSIONING THE EQUIPMENT...........................................................................................................................................................................................25
12.4.1 GENERAL CHECKS PRIOR TO LIGHTING ..................................................................................................................................................................25
12.4.2 EQUIPMENT CHECKS PRIOR TO LIGHTING..............................................................................................................................................................25
12.4.3 PROCEDURE FOR INITIAL LIGHTING .........................................................................................................................................................................26
12.4.4 GAS PRESSURE ADJUSTMENT AND COMBUSTION CHECKS................................................................................................................................26
12.5 WATER HEATER TEMPERATURE ADJUSTMENT PROCEDURE ............................................................................................................................................27
12.6 BOILER TEMPERATURE ADJUSTMENT PROCEDURE ............................................................................................................................................................27
12.7 INSTALLATION NOISE..................................................................................................................................................................................................................27
13.0 LPG FUEL ..............................................................................................................................................................................................................................................27
13.1 RELATED DOCUMENTS ...............................................................................................................................................................................................................27
13.2 PROPANE INJECTORS.................................................................................................................................................................................................................28
13.3 CONVERSION TO LPG..................................................................................................................................................................................................................28
13.4 LPG COMMISSIONING AND TESTING........................................................................................................................................................................................28

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14.0 MAINTENANCE .....................................................................................................................................................................................................................................28
14.1 GENERAL.......................................................................................................................................................................................................................................28
14.2 MAINTENANCE SCHEDULE.........................................................................................................................................................................................................29
14.2.1 ADDITIONAL REQUIREMENTS FOR WATER HEATERS ...........................................................................................................................................29
14.3 DRAINING THE WATER SYSTEM................................................................................................................................................................................................29
14.4 WATER HEATER SERVICING ......................................................................................................................................................................................................29
14.4.1 REMOVING SCALE AND SEDIMENT FROM THE STORAGE VESSEL.....................................................................................................................29
14.4.2 SACRIFICIALMAGNESIUM ANODES ..........................................................................................................................................................................29
14.5 CLEANING THE HEAT EXCHANGER ..........................................................................................................................................................................................30
14.6 REFILLING THE SYSTEM.............................................................................................................................................................................................................31
14.7 OTHER CHECKS............................................................................................................................................................................................................................32
14.7.1 RELIEF VALVES.............................................................................................................................................................................................................32
14.7.2 FLUE SYSTEM................................................................................................................................................................................................................32
14.8 TTB DEVICE...................................................................................................................................................................................................................................32
14.9 FAULT FINDING.............................................................................................................................................................................................................................32
15.0 USER INSTRUCTIONS..........................................................................................................................................................................................................................33

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1.0 INTRODUCTION
•The Lochinvar Mini Copper-Fin range is a floor standing direct gas fired water heater or boiler. The
equipment comprises a copper finned tube heat exchanger surrounded with a high density, light weight
refractory insulation. A durable outer steel jacket assembly provides structural integrity and easy
disassembly. The gas train includes black iron inlet manifold(s) and stainless steel atmospheric burner
assemblies.
•The burners are initiated by a full ignition sequence control that incorporates an intermittent pilot
assembly and rectification supervision of the flame.
•For the correct operation of the appliance when used as a water heater, it is essential that a suitably
sized, glanded-construction bronze pump is utilised to maintain a constant water flow rate through the
heat exchanger. When used as a water heater, the Mini Copper-Fin should also be used in conjunction
with an appropriately sized storage vessel (available from Lochinvar Limited as an ancillary option).
•This equipment is intended for use on Group H Natural Gas (2nd Family) and LPG propane (3rd Family).
The information relating to propane firing is to be found in Section 13: LPG FUEL. This equipment
MUST NOT use gas other than that for which it has been designed and adjusted.
•This equipment must be installed by a competent person, registered with a H.S.E. approved body. All
installations must conform to the relevant Gas Safety and Building Regulations. Health & Safety
requirements must also be taken into account when installing any equipment. Failure to comply with the
above may lead to prosecution.
•If the equipment is to be connected to an unvented (pressurised) system, care must be taken to ensure
all extra safety requirements are satisfied should a high or low-pressure condition occur in the system.
•The equipment is designed for direct connection to a flue system via the draught diverter built in to the
equipment casing. The flue outlets from more than one unit may be connected to a single chimney.
•Ancillary Options:
•Primary Circulating Pump (MCW91-361CE) Omega 4-60-2ZS
•Primary Circulating Pump (MCW401-501CE) Omega 4-90-2ZS
•Direct Storage Cylinder (297 litre) LST66
•Direct Storage Cylinder (450 litre) LST100
•Direct Storage Cylinder (747 litre) LST166
•Direct Storage Cylinder (1155 litre) LST250
•Unvented/Boosted Water System Kits Contact Lochinvar Limited
•De-stratification Pump Kit WH9
•Pre-Fabricated Interconnecting Pipework Contact Lochinvar Limited
•Stacking Frame (MCW/MCB91-181CE) MSF3050
•Stacking Frame (MCW/MCB226-361CE) MSF3051
•Stacking Frame (MCW/MCB401-501CE) MSF3052
•Stacking Frame (MCW + Storage) Contact Lochinvar Limited

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2.0 PRINCIPAL PARTS
FIGURE 2.1 EXPLODED DIAGRAM
FIGURE 2.2 EXPLODED DIAGRAM – CONTROL PANEL ASSEMBLY

6
FIGURE 2.3 EXPLODED DIAGRAM – HEAT EXCHANGER
FIGURE 2.4 EXPLODED DIAGRAM - GAS MANIFOLD ASSEMBLY
ITEM
DESCRIPTION
ITEM
DESCRIPTION
1
Main burnerbar
14
Control thermostat
2
Pilot burner assembly
15
Terminal strip
3
Burner manifold
16
On/off switch
4
Main burner injector
17
Heat exchanger
5
Gas inlet flange
18
‘V’ baffle
6
Manifold flange
19
Temperature gauge
7
Gas valve
20
Pressure/temperature relief valve
8
Gas valve
21
Bulbwell pocket
9
Sequence control
22
Right side fibre board
10
Relay
23
Left side fibre board
11
Time delay relay
24
Front fibre board
12
High limit thermostat
25
Rear fibre board
13
Overheat thermostat
TABLE 2.1 REMOVABLE COMPONENTS

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3.0 TECHNICAL DATA
Model Number
MC91CE
MC136CE
MC181CE
MC226CE
MC271CE
MC316CE
MC361CE
MC401CE
MC501CE
GENERAL DATA
Input (gross) - kW
26.4
39.6
52.8
65.9
79.1
92.3
105.5
117.2
146.5
Input(net) - kW
23.8
35.6
47.0
59.4
71.3
83.1
95.1
105.6
132.0
Output- kW (80°/60°)
20.8
31.0
41.4
52.3
62.7
73.2
83.6
93.0
118.8
Recovery Rate (44
°
∆T) - l/hr
432
648
864
1044
1260
1476
1692
1872
2340
Recovery Rate (50° ∆T) - l/hr
380
570
760
919
1109
1299
1489
1647
2059
Shipping Weight - kg
57
64
71
84
89
99
104
127
132
WATER DATA
Water content - litres
3
3.2
3.4
3.5
3.6
3.7
3.8
4.2
4.5
Water connections (F&R)–
“BSP
2 2 2 2 2 2 2 2 2
Max. Water Pressure - bar
11
11
11
11
11
11
11
11
11
Min. Water Pressure - bar
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
Maximum water temperature
(water heaters) - °C 90 90 90 90 90 90 90 90 90
Maximum water temperature
(boilers) - °C
105 105 105 105 105 105 105 105 105
GAS DATA (G20)
Gas inlet connection – “BSP
¾”
¾”
¾”
¾”
¾”
¾”
¾”
¾”
1”
Gas Flow Rate - m
3
/hr
2.51
3.77
5.03
6.27
7.53
8.79
10.05
11.16
13.91
Burner Pressure - mbar
8.7
8.7
8.7
8.7
8.7
8.7
8.7
8.7
8.7
Minimum Gas InletPressure -
mbar
17.5 17.5 17.5 17.5 17.5 17.5 17.5 17.5 17.5
Maximum Gas Inlet Pressure -
mbar 25 25 25 25 25 25 25 25 25
GAS DATA (G31)
Gas inlet connection – “BSP
¾”
¾”
¾”
¾”
¾”
¾”
¾”
¾”
1”
Gas Flow Rate - m
3
/hr
0.99
1.49
1.98
2.48
2.97
3.47
3.97
4.41
5.51
Burner Pressure - mbar
26.0
26.0
26.0
26.0
26.0
26.0
26.0
26.0
26.0
Minimum Gas InletPressure -
mbar
27 27 27 27 27 27 27 27 27
Maximum Gas Inlet Pressure -
mbar
45 45 45 45 45 45 45 45 45
FLUE DATA
Flue spigot diameter - mm
126
152
178
178
200
200
228
250
250
Flue gas volume - m
3
/min
0.79
1.25
1.64
2.07
2.52
2.92
3.39
3.79
4.73
Maximum flue gas temp. -
⁰
C
140
140
130
130
160
160
160
160
160
TABLE 3.1: TECHNICAL DATA

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FIGURE 3.1: DIMENSIONS
Dimension
Description
MC91CE
MC136CE
MC181CE
MC226CE
MC271CE
MC316CE
MC361CE
MC401CE
MC501CE
A
Overall height of heater
750
750
750
750
750
750
750
750
876
B
Overall width of heater
394
495
597
673
749
825
902
1130
1334
C
Overall depth of heater
546
546
546
546
546
546
546
559
559
D
Centreline of flue
197
248
298
337
375
413
451
565
667
E
Flue diameter
126
152
178
178
203
203
228
254
254
F
Height of gas inlet
171
171
171
171
171
171
171
171
321
G
Centreline of gas inlet
475
475
475
475
475
475
475
475
493
H
Service clearance above
355
355
355
737
737
737
737
737
737
TABLE 3.1: DIMENSIONS
GAS CONNECTION
(TO CENTRE OF GAS INLET)
INLET
OUTLET
RECOMMENDED CLEARANCES
RECOMMENDED CLEARANCES
152
H
260
A
432
610
C
178 159
G
F
E DIA
D
263
610 B152

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4.0 GENERAL REQUIREMENTS
The Lochinvar Mini Copper-Fin has been designed to operate trouble free for many years. These instructions
should be followed closely to obtain the maximum usage and efficiency of the equipment. PLEASE read the
instructions fully before installing or using the appliance.
4.1 RELATED DOCUMENTS
It is law that all gas appliances are installed by competent persons, in accordance with The Gas Safety
(Installation and Use) Regulations 1998. Failure to install appliances correctly could lead to prosecution. It is in
your own interest, and that of safety, to ensure that this law is complied with.
The installation of the equipment MUST be in accordance with the relevant requirements of the Gas Safety
Regulations, Building Regulations, I.E.E. Regulations and the bylaws of the local water undertaking. The
installation should also be in accordance with any relevant requirements of the local gas distributor and local
authority.
In addition the installation should follow the relevant guidance offered in the following documents. It is not
practical to list all relevant information but emphasis is placed on the following documents, as failure to comply
with the guidance given will almost certainly result in an unsatisfactory installation:
BS EN 1858: 2003 Chimneys. Components. Concrete flue blocks
BS 5440-1: 2008 Installation and maintenance of flues and ventilation for gas appliances of rated input
not exceeding 70kW net (1st, 2nd and 3rd family gases)
Part 1: Specification for installation and maintenance of flues
BS 5440-2: 2009 Installation and maintenance of flues and ventilation for gas appliances of rated input
not exceeding 70kW net (1st, 2nd and 3rd family gases)
Part 2: Specification for installation and maintenance of ventilation for gas
appliances
BS 6644: 2005 Specification for Installation of gas fired hot water boilers of rated inputs between
70kW
+ A1: 2008 (net) and 1.8MW (net) (2nd and 3rd family gasses)
BS 6700: 1997 Design, installation, testing and maintenance of services supplying water for
domestic use within buildings and their curtilages
BS 6880: 1988 Code of practice for low temperature hot water systems of output greater than 45kW
Parts 1, 2 and 3
BS 7074: 1989 Application, selection and installation of expansion vesselsand ancillary equipment
Parts 1and 2 for sealed systems
BS 7671: 2008 Requirements for electrical installations, I.E.E. wiring regulations seventeenth edition
CP 342: Code of practice for centralised hot water supply-buildings other than dwellings
Part 2 1974
IGE/UP/1: Installation pipework on industrial and commercial premises
Edition 2
IGE/UP/2: Gas installation pipework, boosters and compressors on industrial and commercial
Edition 2 premises

10
IGE/UP/4: Commissioning of gas fired plant on industrial and commercial premises
Edition 2
IGE/UP/10: Installation of flued gas appliances in industrial and commercial premises
Edition 3
Gas Safety (Installation and Use) Regulations 1998 (England, Scotland & Wales)
CIBSE: Guide parts A, B and C
H.S.E. guidance Automatically controlled steam and hot water boilers
note PM5:
Third edition of the 1956 Clean Air Act Memorandum on Chimney Heights
Manufacturer's notes must not be taken in any way as overriding statutory obligations.
5.0 WATER QUALITY
Water supply quality may adversely affect the efficiency and performance of water heaters and hot water systems.
The situation can intensify where higher temperatures or demands exist.
Water hardness should not exceed 205ppm CaCO3and TDS (Total Dissolved Solids) of untreated water should
not exceed 350ppm. If these values are exceeded, contact Lochinvar Limited for further guidance.
6.0 LOCATION
6.1 PLANT ROOM VENTILATION
The Lochinvar Mini Copper-Fin may only be installed in a room that complies with the appropriate ventilation
requirements. For further details, please refer to Section 9: AIR SUPPLY or to BS5440-2 or BS6644 as
appropriate.
6.2 GENERAL REQUIREMENTS
Corrosion of the heat exchanger and flue system may occur if air for combustion contains certain chemical
vapours. Such corrosion may result in poor combustion and create a risk of asphyxiation. Aerosol propellants,
cleaning solvents, refrigerator and air conditioning refrigerants, swimming pool chemicals, calcium and sodium
chloride, waxes and process chemicals are corrosive. Products of this sort should not be stored near the water
heater or outside by the air intake (if applicable). The fitting of this equipment in a situation where aerosols or
other chemicals may be entrained into the combustion air will invalidate the warranty.
The equipment must be installed on a level, non-combustible surface that is capable of adequately supporting its
weight (when filled with water) and any ancillary equipment. The operation of the equipment must not cause the
temperature of any combustible material in the vicinity of the equipment and its flue to exceed 65°C. If such a
situation is unavoidable, appropriate insulation should be provided.
Locate the equipment so that if the appliance or any connecting pipework should leak, water damage will not
occur. When such locations cannot be avoided it is recommended that a suitable drain pan be installed under the
equipment. The pan should be adequately drained but must not restrict the combustion or ventilation airflow.
6.3 CLEARANCES
The location chosen for the equipment must permit the provision for a satisfactory flue system and an adequate air
supply. The location must also provide adequate space for servicing and air circulation around each unit. This
includes any electrical trunking laid across the floor and to the appliance.
See Figure 3.1 and Table 3.1 for dimensions and clearances. Further details regarding locations are given in
BS5440 or BS6644 as appropriate.

11
7.0 GAS SUPPLY
The Lochinvar Mini Copper-Fin range is suitable for use on second and third family gasses 2H - G20 - 20mbar and
3P - G31 - 37mbar. Details relating to Natural Gas (2H) appear below; for details relating to Propane (3P)
please refer to Section 13: LPG FUEL.
7.1 SERVICE PIPES
The local gas distributor must be consulted at the installation planning stage in order to establish the availability of
an adequate supply of gas. An existing service pipe must not be used without prior consultation with the local gas
distributor.
7.2 METERS
A new gas meter will be connected to the service pipe by the local gas distributor contractor. An existing gas
meter should be checked, preferably by the gas distributor, to ensure that it is adequate to deal with the rate of gas
supply required.
7.3 GAS SUPPLY PIPES
Supply pipes must be fitted in accordance with IGE/UP/2. Pipework from the meter to the equipment must be of
adequate size. The complete installation must be purged and tested as described in IGE/UP/1. Refer to Section
13: LPG FUEL for information on LPG pipework installation guidance.
7.4 BOOSTED SUPPLIES
Where it is necessary to employ a gas pressure booster, the controls must include a low-pressure cut-off switch at
the booster inlet. The local gas distributor must be consulted before a gas pressure booster is fitted. For details of
how to connect a low-pressure cut-off switch, please refer to Section 11: ELECTRICAL SUPPLY.
7.5 PLANT-ROOM CONTROL VALVE
A manual valve for plant-room isolation must be fitted in the gas supply line. It must be clearly identified and
readily accessible for operation, preferably by an exit.
7.6 EQUIPMENT GAS SYSTEM LEAK CHECK
An approved isolating valve and union should be installed for each unit in a convenient and safe position
and be clearly marked. Ensure that the manual gas service valve is in the OFF position. Although the
equipment receives a gas leak check and gas train component integrity check prior to leaving the factory, transit
and installation may cause disturbance to unions, fittings and components. During commissioning a further test
for tightness should be carried out on the equipment gas pipework and components.
Care must be taken not to allow leak detection fluid on or near any electrical parts or connections.

12
8.0 FLUE SYSTEM
8.1 FLUE SYSTEM GENERAL REQUIREMENTS
Detailed recommendations for the flue system are given in BS5440-1 for equipment of rated input not exceeding
70kW net, BS6644 for equipment above 70kW net and IGE/UP/10 for equipment of rated input above 54kW net.
The following notes are intended to give general guidance only.
8.2 FLUE SYSTEMS
Any flue termination must be in such a position as will not cause a hazard to the health of persons who may be
nearby or a nuisance to other persons beyond the curtilage. The flue terminal must be positioned externally such
as to allow the dispersal of products of combustion and air intake. The terminal should be installed in a location
where it will not easily flood or be blocked by snow.
The flue terminal position is very important and must be 1000mm above the roof surfaces or at least 600mm
above any parapet and clear of all adjacent obstructions. It must also be clear of any openable windows,
ventilators or entries that would let flue products from re-entering the building. Recommendations can be found in
BS6644 or BS5440 Part 1 as appropriate.
A minimum of 600mm of vertical flue directly above the draught diverter should be provided where possible on all
draught flue installations. If this dimension cannot be achieved please contact Lochinvar Limited for further
guidance. The weight of the flue must be adequately supported by securing clips and not by the appliance.
The flue system should be designed to maintain atmospheric pressure or a slight suction at the equipment flue
connection at all times within the range of 0.08 to 0.10 mbar (8 to 10 Pascals).
Due to the high thermal efficiency of the equipment, the flue gas temperature is approximately 130°C - 160°C.
Condensation in the flue is thus more likely to occur than with lower efficiency equipment. It is strongly
recommended that twin-wall or insulated flue pipe is used on all installations. Care should be taken to ensure that
the flue is installed such that any condensation is continuously drained. All flues should have a minimum slope of
2° upwards in the direction of the exhaust gas flow. All joints should be such that any condensation is directed
back down the slope to an open drain connection in the flue. The drain pipe must be manufactured from a
corrosion resistant material and be at least 15mm diameter. It must also have a fall of at least 2 to 3° (approx. 3-5
cm per metre) and connect to a drain via a waste trap.
8.3 FLUE MATERIALS – CONVENTIONAL FLUE INSTALLATIONS
•Flue materials, including all jointing materials and fittings should be free from asbestos, durable,
resistant to corrosion and non-combustible.
•When passing up through or adjacent to combustible materials measures need to be taken to prevent
the temperature of the combustible material from exceeding 60°C. The flue must be at least 50mm from
any combustible material unless shielded by a non-combustible sleeve with an air gap of at least 25mm
•Flues shall be of a size not less than specified in Table 3.1. They should be fitted so there is no risk to
anybody in the building and no risk of accidental damage.
•If using an existing brick chimney, a suitable liner should be installed before connecting to the appliance.
The flue should take the shortest possible route and rise continuously to the terminal avoiding the use of
90o bends when there is a change in direction. Horizontal and very shallow runs of flue should be
avoided since they impede the flow of gases and increase local cooling.

13
8.4 MULTIPLE FLUE INSTALLATION
•Common flues may be used on multiple installations only if all the heaters are of the same burner
system and fuel type and should be sized to ensure complete evacuation of the flue products from the
installation.
•Where one appliance is to be used more regularly or for longer periods than the others in the group, it
should be connected at the point nearest the main flue. Please refer to BS6644 for further information
and recommendations.
•A split collar should be fitted above the draught diverter so that the flue is secure but can be
disconnected for servicing. The weight of the flue must be adequately supported by securing clips and
not by the heater.
•If a 600mm vertical rise before connection to the common header is not possible, the common header
should be sized to ensure adequate evacuation of all products of combustion.
8.5 FAN DILUTION SYSTEMS
An alternative to a natural draught flue system is a Flue dilution system, which is suitable for connection to the Mini
Copper-Fin’s but must be properly designed by a specialist flue company.
8.6 BALANCED COMPARTMENTS
The equipment is suitable for siting within a balanced compartment. This compartment must be designed by a
specialist company.
9.0 AIR SUPPLY
The following information is based on single appliance installations only. If more than one appliance is being
used, BS5440-2 or BS6644 (as appropriate) should be consulted to calculate the necessary requirements.
This is a Type B11 appliance and must be installed outside or in a room separated from inhabited rooms
with suitable ventilation directly to the outside.
9.1 NATURAL VENTILATION
The combustion air requirements are as follows:
Model
Gross
Input
(kW)
Net
Input
(kW)
Ventilation
(Room)
(cm2)
Compartment Compartment
(Direct to Outside) (To Internal Space)
High
(cm
2
)
Low
(cm
2
)
High
(cm
2
)
Low
(cm
2
)
MC91CE
23.8
26.4
106
132
264
264
528
MC136CE 35.6 39.6 160 199 396 396 792
MC181CE
47.0 52.8 212 264 528 528 1056
MC226CE 59.4 65.9 264 330 659 659 1318
TABLE 9.1 COMBUSTION VENTILATION REQUIREMENTS MC91CE – MC226CE

14
Model Gross Input
(kW)
Net
Input
(kW)
Plant Room Enclosure
Low
Summer Use
Medium
Summer Use
High
Summer Use
Low
Summer Use
Medium
Summer Use
High
Summer Use
High
(cm
2
)
Low
(cm
2
)
High
(cm
2
)
Low
(cm
2
)
High
(cm
2
)
Low
(cm
2
)
High
(cm
2
)
Low
(cm
2
)
High
(cm
2
)
Low
(cm
2
)
High
(cm
2
)
Low
(cm
2
)
MC271CE
79.1
71.3
143
286
214
357
286
428
357
713
428
785
500
856
MC316CE 92.3 83.1 167 333 250 416 333 500 416 831 500 916 583 999
MC361CE
105.5
95.1
190
380
285
475
380
570
475
951
570
1045
665
1140
MC401CE 117.2 105.6 212 423 317 528 423 634 528 1056 634 1162 740 1268
MC501CE
146.5 132.0 264 528 396 660 528 792 660 1320 792 1452 924 1584
TABLE 9.2 COMBUSTION VENTILATION REQUIREMENTS MC271CE – MC501CE
9.2 MECHANICAL VENTILATION
To comply with the relevant installation standards, (BS5440-2:2009 for appliances with net heat inputs below
70kW and BS6644:2005 for appliances with net heat inputs between 70kW and 1.8MW) combustion ventilation
must be provided for all open flued appliances. In situations where this cannot be provided by the means of
ventilation grilles, combustion air can be supplied by a fan. The minimum flow rate for the fan should be in
accordance with Table 9.3.
If required, extract air can also be through the use of a fan. When sizing the extract fan, the extract flow rate
should be calculated by subtracting the difference volume (from Table 9.3) from the actual supplied volume of inlet
air. If therefore, a larger than required inlet volume is provided, the extract flow rate will need to be increased
accordingly.
If the ventilation discharge from the plant room is through the means of simple openings relying on thermal effects,
the minimum free areas of the openings and any associated grilles should be as specified for natural ventilation
(see separate “Free Area Requirements – Combustion” specification sheet). The ventilation openings shall be at
high level and the air supply shall be at low level.
Ventilation must not be provided through natural inlet and mechanical extract as this will cause a negative
pressure within the plant room and may lead to the products of combustion being drawn into the plant room.
When using mechanical ventilation systems, an automatic control should be used to cause a safety shut-down of
the burner in the event of failure of air-flow either inlet or extract ducts.
NOTE: VENTILATION MUST NOT BE PROVIDED THROUGH NATURAL INLET AND
MECHANICAL EXTRACT AS THIS WILL CAUSE A NEGATIVE PRESSURE WITHIN THE PLANT ROOM AND
MAY LEAD TO THE PRODUCTS OF COMBUSTION BEING DRAWN INTO THE PLANT ROOM.
Appliance Type
Flow rate per kW total rated net input (m3/h)
Minimum Inlet Air
(Combustion, Ventilation)
Difference between Inlet and Extract Air
(Inlet minus Extract Ventilation)
With draught diverters
2.80
2.07 ± 0.18
Without draught diverters.
(with or without draught stabilisers) 2.60 1.35 ± 0.18
TABLE 9.3 MECHANICAL VENTILATION FLOW RATES
Worked Example – Mechanical inlet/natural discharge:
Lochinvar MC361CE
Heat input (net):
=
95.1 kW
Minimum combustion air flow rate:
=
95.1 x 2.8 m
3
/h
=
266.28 m
3
/h
Ventilation grille size (high level):
=
192 cm
2

15
Worked Example – Mechanical inlet/mechanical discharge (minimum combustion air flow rate):
Lochinvar MC361CE
Heat input (net):
=
95.1 kW
Minimum combustion air flow rate:
=
95.1 x 2.8 m
3
/h
=
266.28 m
3
/h
Difference between inlet and extract air
(maximum value):
=
95.1 x (2.07 + 0.18) m3/h
=
213.98 m3/h
Difference between inlet and extract air
(minimum value):
=
95.1 x (2.07 - 0.18) m
3
/h
=
179.74 m
3
/h
Extract air (maximum value):
=
266.28 m
3
/h – 179.74 m
3
/h
=
86.54 m
3
/h
Extract air (minimum value):
=
266.28 m
3
/h – 213.98 m
3
/h
=
52.30 m
3
/h
Worked Example – Mechanical inlet/mechanical discharge (alternate combustion air flow rate):
Lochinvar MC361CE
Heat input (net):
=
95.1 kW
Minimum combustion air flow rate:
=
95.1 x 2.8 m
3
/h
=
266.28 m
3
/h
Actual combustion air flow rate:
=
95.1 x 3.15 m3/h
=
299.57 m3/h
Difference between inlet and extract air:
(maximum value)
=
95.1 x (2.07 + 0.18) m
3
/h
=
213.98 m
3
/h
Difference between inlet and extract air:
(minimum value)
=
95.1 x (2.07 - 0.18) m3/h
=
179.74 m3/h
Extract air (maximum value):
=
299.57 m3/h – 179.74 m3/h
=
119.83 m3/h
Extract air (minimum value):
=
299.57 m3/h – 213.98 m3/h
=
85.59 m3/h

16
10.0 WATER CONNECTIONS
10.1 WATER HEATERS
10.1.1 GENERAL
Mini Copper-Fin water heaters require a minimum flow rate and should also be supplied with separate storage
vessels. Suitably sized pumps and separate storage vessels are available from Lochinvar Limited as ancillary
options.
Note: Lochinvar Limited recommends the use of glanded bronze pumps.
Recommended pipework layouts are available for different water heater and storage vessel combinations. Please
contact Lochinvar Limited for details. When multiple units are connected using common pipework, it is
recommended that a reverse-return arrangement is used to ensure equal flowthrough each unit.
The requirements of minimum water flow are given in Table 10.2. Recommendations for the water circulation
system are given in BS6644 and CP 342. The following notes are of particular importance.
1. When the unit is being utilised as a direct-fired water heater it is designed for use with a direct type
storage vessel. Contact Lochinvar Limited for help in sizing the storage vessel
2. Circulating pipework not forming part of the useful heating surface should be insulated. Cisterns,
expansion vessels and pipework situated in areas exposed to freezing conditions should also be
insulated.
3. Drain valves must be located in accessible positions that will permit draining of the entire system
including the unit and the storage vessel.
4. Tapping sizes for connection to the water system are detailed in Table 3.1.
5. Ideally, individual valves should be fitted to each unit to enable isolation from the system. The
arrangement must comply with the requirements of BS6644.
6. Every system should be provided with a water gauge complete with isolating valve so that the pressure
of the system may be displayed for commissioning and maintenance purposes.
10.1.2 OPEN VENTED SYSTEM ARRANGEMENT
The Lochinvar Mini Copper-Fin can be used in an open vented arrangement provided that a vent pipe in
accordance with CP342, BS6644 or BS6700 as appropriate is fitted. The minimum static head requirement for an
open vented system is 0.5 bar.
10.1.3 UNVENTED SYSTEM ARRANGEMENT
NOTE: IT IS STRONGLY RECOMMENDED THAT UNVENTED HOT WATER SYSTEMS BE
INSTALLED BY AN APPROVED INSTALLER.
If the Lochinvar Mini Copper-Fin is to be used in an unvented arrangement, the system should follow the guidance
given in BS6700 and must comply with The Building Regulations: Part G3. A kit of components that have been
suitably sized for the unvented operation of the appliance is available from Lochinvar Limited. For further
information, contact Lochinvar Limited.
10.1.4 WATER PRESSURE GAUGE
Every system should be provided with a gauge complete with isolating valve so that the pressure of the system
may be displayed for commissioning and maintenance purposes.
10.1.5 DRAIN VALVES
Each unit should be provided with a 15mm drain valve fitted into the return to enable the heat exchanger to be
drained without draining the entire system.

17
10.1.6 EXPANSION VESSEL SIZING
The following information is based on an inlet pressure of 3.5 bar. If a different inlet pressure is to be used, please
consult BS6700.
V V =
0.45
S V * e
Where:
V V = Vessel Volume
S V = System Volume
e = Coefficient of Expansion (See Table 10.1)
Stored
Temp.
°
C
30 35 40 45 50 55 60
e 0.005 0.006 0.008 0.010 0.012 0.015 0.017
Stored
Temp.
°
C
65 70 75 80 82 85 90
e 0.020 0.023 0.026 0.030 0.031 0.033 0.037
TABLE 10.1 COEFFICIENT OF EXPANSION OF WATER AT 3.5 BAR INLET PRESSURE
10.1.7 DE-STRATIFICATION
If the hot water system does not include a constantly circulated building return, it is recommended that a de-
stratification pump be fitted, between the flow connection and the circulation connection on the right hand side of
the storage vessel, to ensure an even temperature distribution throughout the stored water. De-stratification pump
kits are available as ancillary items; please contact Lochinvar Limited for details.
10.1.8 CIRCULATING PUMPS
In order to ensure the correct flow rates through the water heater, the unit requires a bronze glanded pump sized
to overcome the resistance of the heat exchanger and a primary pipework loop. The primary loop should be no
longer than 14 metres plus the following fittings:
6 x 90°Elbows
2 x Unions
2 x Full bore lever ball valves
2 x Tee fittings (cold feed & HWS return)
For longer distances or a greater number of fittings, the pump may have to be resized.
The specification of this type of pump ensures that the bronze body and associated parts in contact with water are
suitable for potable use. A "glanded" construction is required to ensure that any scale in the system does not build
up within the pump and cause a resistance that can lead to a loss of water flow. Glandless (canned rotor) pumps
are not recommended by Lochinvar Limited due to the fact that in hard water areas, scale can build up within the
rotor and failure can occur, not only of the pump but also the heater itself. The warranty will be void if a failure of
the heat exchanger occurs due to a "glandless" pump.

18
Model Differential - K Flow – l/s
Total System Pressure
Loss - Metre H20
MCW91CE 3 1.9 2.44
MCW136CE 4 1.9
2.44
MCW181CE 5 1.9
2.44
MCW226CE 6 1.9
2.44
MCW271CE 8 1.9
2.44
MCW316CE 9 1.9
2.44
MCW361CE 11 1.9
2.44
MCW401CE 12 1.9
2.44
MCW501CE 15 1.9
2.44
TABLE 10.2 WATER HEATER FLOW RATES
To ensure proper velocity through the heat exchanger, it is necessary to balance the temperature rise across the
heat exchanger from inlet to outlet. Excessive scale build up in the tubes is a result of too little velocity; excessive
pitting or erosion on the inside of the tubes is caused by too much velocity. Care should be taken to measure the
temperature rise and maintain a constant velocity as follows:
1. Thermometers are installed on the inlet and outlet of the equipment to measure water temperature
entering and leaving.
2. The pump should run continuously.
3. With the pump in operation and the burner “off”, both thermometers should read the same temperature.
4. Switch the burner on and allow the temperature to stabilise. Record the difference between the inlet and
outlet temperature. The difference will be the “temperature rise”.
5. Compare the temperature rise with the required figure shown in Table 10.2.
A. If the temperature rise is too high, water velocity is too low. Check the following:
1. No restrictions in the outlet of the heater.
2. All valves are open between the heater and the storage vessel.
3. Pump is running in the proper direction.
4. Pump size is correct.
5. Pipework size is correct.
B. If the temperature rise is too low, water velocity is too high. Adjust accordingly.
1. Throttle the valve on the outlet side of the heater, until temperature rise is steady and at correct
value shown in Table 10.2.
2. Periodically check the temperature rise to ensure proper operation.
10.1.9 PIPEWORK SIZE
The pipework for the primary circulating loop should be in accordance with the following table. If more than one
water heater is to be connected to common circulating pipework, the common sections need to be sized in
accordance with the following table:
1 x MCW 2 x MCW 3 x MCW
Pipe Size 54mm 67mm 76mm
TABLE 10.3 PIPE SIZES

19
10.2 HEATING BOILERS
10.2.1 GENERAL
The Mini Copper-Fin boiler requires a minimum water flow rate through the heat exchanger. A suitably sized
primary circulating pump is available from Lochinvar Limited as an ancillary option.
Recommended pipework layouts are available; please contact Lochinvar Limited for details. When multiple units
are connected using common pipework, it is recommended that a reverse-return arrangement is used to ensure
equal flow through each unit.
The requirements of minimum water flow are given in Table 10.4. Recommendations for the water circulation
system are given in BS6644 and CP 342. The following notes are of particular importance.
1. Circulating pipework not forming part of the useful heating surface should be insulated. Cisterns,
expansion vessels and pipework situated in areas exposed to freezing conditions should also be
insulated.
2. When the unit is being utilised as a combined central heating and domestic hot water boiler the hot water
vessel must be of the indirect type.
3. Drain valves must be located in accessible positions that will permit draining of the entire system
including the unit.
4. Tapping sizes for connection to the heating system are detailed in Table 3.1.
5. Ideally, individual valves should be fitted to each unit to enable isolation from the system. The
arrangement must comply with the requirements of BS6644.
6. Every system should be provided with a water gauge complete with isolating valve so that the pressure
of the system may be displayed for commissioning and maintenance purposes.
10.2.2 OPEN VENTED SYSTEM ARRANGEMENT
The Lochinvar Mini Copper-Fin can be used in an open vented arrangement provided that a vent pipe in
accordance with CP342 or BS6644 as appropriate is fitted. The minimum static head requirement for an open
vented system is 0.5 bar.
10.2.3 SEALED SYSTEM ARRANGEMENT
If a sealed system arrangement is required, a suitable pressurisation unit is available from Lochinvar Limited on
request. Sealed systems should incorporate a safety valve with a lift pressure no greater than the maximum
pressure rating of any component in the heating system. The maximum working pressure of the boiler is 11.0 bar.
A suitably sized expansion vessel should also be fitted to the system.
10.2.4 DRAIN VALVES
Each unit should be provided with a 15mm drain valve fitted into the return to enable the heat exchanger to be
drained without draining the entire system.

20
10.2.5 EXPANSION VESSEL SIZING
The following information is based on a static head of 35 metres and a cold fill pressure of 3.8 bar:
V V =
0.45
S V * e
Where:
V V = Vessel Volume
S V = System Volume
e = Coefficient of Expansion (See Table 10.1)
10.2.6 PRIMARY CIRCULATING PUMPS
The Lochinvar Mini Copper-Fin boiler may need a primary pump to ensure correct flow through the boiler and a
secondary pump to circulate water around the heating system. Pump selection must ensure that the flow rate
through the unit is in accordance with that stated in Table 10.4. The pump should be sited to facilitate servicing. It
is important that the existing pump size is checked when the boiler is being used for a refurbishment project, to
ensure that the minimum flow rate can be achieved.
Model Differential - K Flow – l/s
Total System Pressure
Loss - Metre H20
MCB91CE
20
0.12
0.06
MCB136CE
20
0.20
0.06
MCB181CE
20
0.24
0.06
MCB226CE
20
0.36
0.09
MCB271CE
20
0.48
0.12
MCB316CE
20
0.58
0.12
MCB361CE
20
0.70
0.15
MCB401CE
20
0.85
0.40
MCB501CE
20
0.97
0.46
TABLE 10.4 SYSTEM HEAD LOSS
Primary circulating pumps are available as ancillary items; please contact Lochinvar Limited for details
FIGURE 10.1 BOILER PRIMARY/SECONDARY ARRANGEMENT