andrews HIflo EVO HF 30/300 Manual

Please read and understand these instructions before commencing installation and leave this manual with the customer for future reference.
Andrews. Built to perform.
HIflo EVO range - Gas fired storage water heaters for natural gas LPG
HF 30/300, HF 48/300, HF 65/300, HF 48/380, HF 65/380
Issue 4 21042918

Andrews Water Heaters
Reproduction of any information in this publication by any
method is not permitted unless prior written approval has been
obtained from Andrews Water Heaters.
Andrews Storage Water Heaters have been designed and
manufactured to comply with current international standards of
safety. In the interests of the health and safety of personnel and
the continued safe, reliable operation of the equipment, safe
working practices must be employed at all times. The attention
of UK users is drawn to their responsibilities under the Health
and Safety Regulations 1993.
All installation and service on Andrews Water Heaters must be
carried out by properly qualified personnel and, therefore, no
liability can be accepted for any damage or malfunction caused
as a result of intervention by unauthorised personnel.
Andrews Water Heaters’ policy is one of continuous product
improvement and, therefore, the information in this manual,
whilst completely up to date at the time of publication, may be
subject to revision without prior notice.
Further information and assistance can be obtained from:
Customer support
Monday - Friday
8am - 5pm
Sales: 0345 070 1055
Technical: 0345 070 1057
Email: comm[email protected]
Website: www.andrewswaterheaters.co.uk
Twitter: @andrewsWH
Note
The Andrews Water Heaters covered in this manual
are for use with natural gas and LPG only
Copyright Andrews Water Heaters 2018
Issue 4 21042918

Contents
1.1 General Information ..........................................................................................................................4
1.2 British Standards and Codes of Practice...........................................................................................4
1.3 Health and Safety Regulations 1993 .................................................................................................5
1.4 Effectiveness in Combating Legionella..............................................................................................5
2 Technical Data..........................................................................................................................................6
2.3 ErP data............................................................................................................................................9
3.2 Location ..........................................................................................................................................10
3.3 Flue System....................................................................................................................................10
3.4 Air Supply .......................................................................................................................................13
3.5 Important.........................................................................................................................................14
3.6 Water Quality and Treatment...........................................................................................................15
3.7 Water Connections - General..........................................................................................................16
3.9 Gas Connections ............................................................................................................................19
3.10 Electrical Supply .............................................................................................................................19
3.11 Wiring Diagram ...............................................................................................................................20
4 Commissioning ......................................................................................................................................21
4.1 HIflo EVO........................................................................................................................................21
4.2 Users Safety Guide.........................................................................................................................22
5 Operation ...............................................................................................................................................23
5.1 Burner Assembly.............................................................................................................................23
5.2 Burner flame check .........................................................................................................................24
5.4 Temperature selection procedure....................................................................................................25
6.1 Servicing .........................................................................................................................................30
6.2 Burner Assembly.............................................................................................................................32
6.3 Gas Control Valve ...........................................................................................................................33
6.4 Descaling Information .....................................................................................................................34
6.5 Accessing service mode on the water heater display (Service personnel only) ...............................35
6.6 How to reset the control from Lockout conditions............................................................................44
6.7 Diagnostic error codes and troubleshooting procedures for Honeywell integrated...........................47
7 Fault Finding ..........................................................................................................................................49
7.1 Andrews HIflo EVO .........................................................................................................................49
8 Parts List................................................................................................................................................50
8.1 Water Heater Full Assembly............................................................................................................50
8.2 Combustion Assembly ....................................................................................................................51
8.3 Ignition Control Assembly and Harness ........................................................................................52
8.4 General Assembly Parts List ...........................................................................................................53
9 Appendix................................................................................................................................................55
9.1 Dismantling, Disposal and Recycling ..............................................................................................55
© Copyright...................................................................................................................................................55
Issue 4 21042918

1 General and Safety Information
General and Safety Information 1
1.1 General Information
The Andrews Water Heater has been designed for use with
NATURAL GAS & LPG only and is manufactured to give an
efficient, reliable and long service life.
To ensure the continued, trouble-free operation of your heater at
maximum efficiency, it is essential that correct installation,
commissioning, operation and service procedures are carried
out strictly in accordance with the instructions given in this
manual. By law, installation and commissioning of the heater
must be carried out by properly qualified personnel.
The heater(s) must be installed in accordance with the following
requirements;
The current GAS SAFETY (INSTALLATION AND USE)
REGULATIONS
The current BUILDING REGULATIONS
The Water Supply (WATER FITTINGS) REGULATIONS 1999
Additionally, installation should be performed in accordance with
all relevant requirements of the Gas Supplier, Local Authority
and recommendations of the British Standards and Codes of
Practice detailed below.
1.2 British Standards and Codes of Practice
1.2.1 HIflo EVO
BS 6700: Specification for design, installation, testing
and maintenance of services supplying water
for domestic use within buildings and their
curtilages. This standard supersedes the
following British Standards and Codes of
Practice: CP99, CP310, CP324, 202, CP342
Part 2, Centralised Hot Water Supply.
BS 5440: Installation of flues and ventilation for gas
appliances of rated output not exceeding
60kW.
Part 1: Specification for installation of flues.
Part 2: Specification for installation of ventilation for
gas appliances.
BS 5546: Installation of gas hot water supplies for
domestic purposes.
BS 6891: Installation of low pressure gas pipework of up
to 28mm in domestic premises.
BS 7206: Specification for unvented hot water storage
units and packages.
BS EN 806 (Parts 1 - 5) Specifications for installations
inside buildings conveying water for human
consumption.
BS 6644 Installation of gas fired water boilers of rated
inputs between 70kW and 1.8MW.
BS EN 12897 Water supply. Specification for indirectly
heated unvented (closed) storage water
heaters.
IGE/UP/1A,1B Strength/tightness testing and direct purging.
IGE/UP/2 Installation pipework.
IGE/UP/10 - 1 (Edition 4): Installation of gas appliances in
industrial and commercial premises.
Note
Consideration should be given to amendments or
updates to the above standards.
4
Issue 4 21042918

1 General and Safety Information
1.3 Health and Safety Regulations 1993
It is the duty of manufacturers and suppliers of products for use
at work to ensure, so far as is practicable, that such products
are safe and without risk to health when properly used and to
make available to users, adequate information about their safe
and proper operation.
Andrews Water Heaters should only be used in the manner and
purpose for which they were intended and in accordance with
the instructions in this manual. Although the heaters have been
manufactured with paramount consideration to safety, certain
basic precautions specified in this manual must be taken by the
user.
It is imperative that all users of the heater must be provided with
all the information and instruction necessary to ensure correct
and safe operation.
1.4 Effectiveness in Combating Legionella
Water systems in buildings have been associated with outbreaks
of Legionnaires' Disease, particularly in health care facilities
where occupants are significantly more susceptible to infection.
In recognition of the risks in hospitals, a Code of Practice for the
Control of Legionella in Health Care premises has been issued
by the Department of Health (1991). Codes of Practice
applicable to other premises have been published by other
organisations, principally the Health and Safety Executive
(HS)(G70) and the Chartered Institute of Building Services
Engineers (CIBSE, TM13).
All Codes of Practice draw attention to the design and operation
of water systems with reference to avoidance of factors that
favour colonisation by legionella bacteria. These factors include
stagnation, lukewarm conditions (20°C to 45°C) and the
accumulation of debris, scale and corrosion in the base of tanks
and calorifiers.
Andrews Water Heaters has commissioned an independent
evaluation of their products to investigate their resistance to
build-up of legionella bacteria.
Experiments were conducted to determine whether, following a
substantial challenge by legionella pneumophilia, after overnight
and stagnation conditions, the system was rendered free from
viable recoverable legionella. It was found that at 61°C, following
a challenge of approximately 107 organisms per litre, within one
hour, more than 99.999% of organisms had been killed. After a
subsequent stagnation period, sampling did not reveal any
residual contamination. The design of the base of the water
heater precludes legionella colonisation, even after build-up of
debris. The burner positioning ensures that the water at the
bottom of the heater reaches the same, or higher temperature
as in the rest of the heater.
Based on data obtained through experiment, the Andrews Water
Heater can be described as legionella resistant as it is
considered unlikely that, at the temperature tested, the organism
would colonise the water heater and present a possible health
risk.
5
Issue 4 21042918

2 Technical Data
2.1 Appliance Dimensions
Model HF 30/300 HF 48/300 HF 65/300 HF 48/380 HF 65/380
Amm 1600 1645 1645 1861 1861
Bmm 127 152 152 152 152
Cmm 254 254 254 254 254
Dmm 1118 1118 1118 1334 1334
Emm 1194 1194 1194 1410 1410
Fmm 1556 1556 1556 1772 1772
Gmm 1416 1416 1416 1607 1607
Hmm 762 762 762 762 762
Jmm 718 718
718 718 718
Kmm 1391 1319 1319 1607 1607
Table 1
Figure 1
6
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Technical Data 2
2 Technical Data
2.2 HIflo EVO connections & technical data
Natural Gas
Andrews Models
Unit
HF30/300 HF48/300 HF65/300 HF48/380 HF65/380
Input (gross) kW 37 59 79 59 79
Input (net) kW 33.3 53.1 71.1 53.1 71.1
Output (gross) kW 30.34 48.38 64.78 48.38 64.78
Efficiency (net CV) %91 91 91 91 91
Efficiency (gross thermal) %82 82 82 82 82
Gas Flow Rate (NG) m3/hr 3.41 5.44 7.38 5.44 7.38
NOx ppm 10 20 10 20 20
NOx mg/kWh 17.6 35.2 17.6 35.2 35.2
CO2 Flue Gas %8.00 - 8.50
8.50 - 9.00 8.00 - 8.50 8.50 - 9.00 8.50 - 9.00
Noise Level dBA 51 51 51 51 51
Recovery Rate (through 50°C rise) l/h 520 829 1111 829 1111
Recovery Rate (through 56°C rise) l/h 464 741 992 741 992
Minimum Flow Rate l/s N/A N/A N/A N/A N/A
Water Content Litres 303 303 303 380 380
Weight Empty Kg 210 210 214 250 250
Weight Full Kg 510 510 515 628 628
Shipping Weight Kg 243 243 247 287 287
Storage Losses kWh/l/day N/A N/A N/A N/A N/A
Inlet/Outlet Connections Inch BSP 1 1/2”1 1/2”1 1/2”1 1/2”1 1/2”
Return Connection Inch BSP 3/4” 3/4” 3/4” 3/4” 3/4”
Gas Connection Inch BSP 3/4” 3/4” 3/4” 3/4” 3/4”
Flue Diameter (secondary) mm 127 150 150 150 150
Flue Diameter (concentric) mm N/A N/A N/A N/A N/A
Ionisation Current (min) µA1.0 1.0 1.0 1.0 1.0
Ionisation Current (max) µA30 30 30 30 30
HSI Resistance KΩN/A N/A N/A N/A N/A
Electrical Requirements V230 230 230 230 230
Power Consumption W120 210 210 210 210
Fuse Rating A55555
Maximum Flue Gas Temperature °C 230 230 230 230 230
Maximum Flue Static Pressure mbar -0.02 -0.02 -0.02 -0.02 -0.02
Waterside Pressure Loss kPa N/A N/A N/A N/A N/A
Maximum Outlet Temperature °C 80 80 80 80 80
Maximum Working Pressure Bar 10.3 10.3 10.3 10.3 10.3
Minimum Working Pressure Bar 3.0 3.0 3.0 3.0 3.0
Diameter mm 718 718 718 718 718
Height
mm
1600 1645 1645 1860 1860
7
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Technical Data 2
2.3 ErP data
HIflo EVO HF 30/300 HF 48/300 HF 65/300 HF 48/380 HF 65/380
Declared load profile XL XL XL
XL XL
Water heating energy efficiency class
Water heating energy efficiency %74.5 72 69.5 67 67.3
Annual energy consumption kWh (1) 68 71 50.5 69
Annual energy consumption GJ
(2) 20 20 21 22 22
Other load profiles for which the water heater is suitable to use and
the corresponding water heating energy efficiency and annual
electricity consumption(3) - - - - -
Thermostat temperature setting °C 60 60
60 60 60
Sound power level L
WA
indoors
dB
51 51 51 51 51
Ability to off
-
peak hours functioning
(3) No No No No No
Enables
smart control settings
(4) - - - - -
(1) Electricity
(2) Fuel
(3) If applicable
(4)
If smart control setting value is "1", the water heating energy efficiency, annual electricity and fuel consumption only rela
te to enabled
smart control settings
HIflo EVO Natural Gas HF 30/300 HF 48/300 HF 65/300 HF 48/380
HF 65/380
Daily electricity consumption Qelec kWh 0.001
0.001 0.001 0.001 0.001
Declared load profile X
L
XL XL XL XL
Sound power level, indoors LWA dB 51 51 51 51 51
Daily fuel consumption Qfuel kWh 25.50 27.00 28.50 29.75 30.10
Emissions of nitrogen oxides NOxmg/kWh 17.6 35.2 17.6 35.2 35.2
Weekly fuel consumption with smart controls Qfuel, week, smart kWh - - - - -
Weekly electricity consumption with smart controls Qelec, week, smart kWh - - - - -
Weekly fuel consumption without smart controls Qfuel, week kWh 178.50 189.00 199.50 208.25
210.70
Weekly electricity consumption without smart controls Qelec, week kWh 0.335 0.355 0.330 0.325 0.320
Storage volume VI303 303 303 380 380
Mixed water at 40 °C V40 I
∞
∞
∞
∞
∞
Harmonised standards applied EN: 13203-2
Specific precautions that shall be taken when the
water heater is assembled, installed or maintained:
Before any assembly, installation or maintenance the installation and
operation manual has to be read attentively and be followed
8
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3 Installation
3 Installation
3.1 Introduction
The law requires that installation is carried out by a
properly qualified person.
Install in accordance with current British Standard Code of
Practice 342 part 2 and British Standards 5440, 5546, 6644,
6700, 6798 and 6891.
3.2 Location
The location chosen for the heater must permit the provision of a
satisfactory flue and an adequate air supply.
The heater must not be installed in a room which contains a
bath or a shower and must not be installed in a bedroom or
bedsitting room.
A clearance of 300mm should be left around the heater for fitting
and servicing purposes and 762mm above the heater for
removal of the flue baffle. The above clearances are
recommended for ease of servicing. They can be reduced if
necessary but a clearance of 300mm must be left in front of
heater for access to the burner and controls. The flue baffle
clearance should also be maintained if possible to avoid
servicing problems.
The floor on which the heater is installed must be flat, level and
of sufficient strength to withstand the weight of the heater when
filled with water, and should satisfy the requirements of the Local
Authority & Building Regulations.
Any combustible material adjacent to the heater must be so
placed or shielded as to ensure that its temperature does not
exceed 65°C.
3.3 Flue System
See
Detailed recommendations for flueing are given in British
Gas booklet IM/11, BS 5440 part 1, BS6644 and
IGE/UP/10. The following notes are intended to give
general guidance:
Note
• Route. The route of the flue is not critical but, when
planning, horizontal runs must be kept to a minimum.
9
Issue 4 21042918

Recommendations for flue installation are given in BS 6644,
BS5440 Pt 1 and British Gas publication IM/11 - Flues for
Commercial and Industrial Gas Fired Boilers and Air Heaters.
The flue connection is designed for BS 835 type heavy duty flue,
but light quality flue pipe, mild steel or stainless steel sheet may
be used using the appropriate adapter. Flue pipes etc. shall be
fitted socket-up to keep any condensate within flue and
appliance. Flues up to 200mm diameter should be fitted with a
suitable British Gas Certified terminal.
Figure 2
The terminal position is most important and must be at least
1000mm above roof surfaces or at least 600mm above any
parapet and clear of any adjacent obstruction as well as being
clear of any openable windows, ventilators or features which
could allow re-entry of flue products into the building. Pressure
areas should also be avoided to prevent blowdown.
See recommendations in BS 6644. BS 5440 Part
1 also provides useful additional advice.
Flue materials, including jointing materials and fittings shall be
asbestos-free, robust, durable, corrosion resistant and non-
combustible and shall comply with BS 5854 and BS 715 or BS
4076 as appropriate, as well as being of a type accepted by the
Local Gas Authority.
When passing up through or adjacent to combustible
materials, measures shall be taken to prevent the temperature
of the combustible material from exceeding 60°C. The flue
shall not be closer than 50mm to any combustible material
except when passing through, when it must be enclosed by a
non- combustible sleeve and separated from the sleeve by not
less than 25mm air space.
Flues shall be of a size not less than specified in Section 2,
Technical Data (i.e. nominal flue size) and fitted so that there is
no risk to persons in the building or from accidental damage
If using an existing brick chimney, it should be swept and lined
and checked for soundness before connecting the flue and
should take the shortest possible route and rise continuously to
the terminal avoiding the use of 90° bends where a change of
direction is required. Horizontal and very shallow runs of flue
should be avoided since they impede the flow of gases and
increase local cooling.
*A minimum of 600mm of vertical flue directly above the draught
diverter should be provided where possible on all natural draught
flue installations. If this dimension cannot be achieved please
contact Andrews Water Heaters.
Note
Please note this is not required where a common
flue header is used on multiple installations.
Terminal
1000mm
Minimum
Roof
1 2 3
Split flue clip
600mm*
1. This flue run
must not be used
2 & 3 are recommended flue runs
Figure 2
Figure 3
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Minimum Heights from Roof to Base of Flue Terminal
Type of Roof
Not within 1.5m of a
vertical surface of a
structure = on the roof
Within 1.5m of a
vertical surface of a
structure = on the roof
Internal Route External
Route
Internal
Route
External
Route
On Ridge Not on Ridge
Pitched
Pitch
exceeding
45°
At or
above
ridge
level
1m
above roof
intersection
1m
above roof
intersection
The base of the
terminal should
be 600mm
above the level of
the adjacent roof
edge
Pitch not
exceeding
45°
600mm
above roof
intersection
The base of
the terminal
should be
600mm
above the
level of the
adjacent
roof edge
Flat
With
parapet Not
applicable
600mm
above roof
intersection
Without
parapet
250mm
above roof
intersection
Figure 4
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 flue is to be used more regularly or for
longer periods than the others in the group, it should
be connected at the point nearest to the main flue
See BS 6644 Clause 20 for further
information and recommendations on this
as well as general flue requirements.
Fit a flue clip or flange joint close to the diverter
so that it is secure but can be disconnected for
servicing. The weight of the flue must be borne
by securing clips, etc. and not by the heater
Each unit has an
atmospheric burner
system & uses natural
gas.
Heater with
highest usage
fitted nearest to
main flue
(if applicable)
Figure 4
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3.4 Air Supply
See
Detailed recommendations for air supply are given in BS
5440 part 2 and BS6644 for installations exceeding
70kW.
The following notes are intended to give general guidance:
Where the heater is to be installed in a room or internal space
the heater requires the room or internal space containing it to
have a permanent air vent. The vent must be direct to outside
air
Where the heater is to be installed in a compartment, permanent
air vents are required in the compartment at high and low level.
These air vents must either communicate with a room or internal
space or be direct to outside air.
The minimum effective areas of the permanent air vents
required are as follows:-
Air Vent Areas
Position of Air Vents Air from room or internal space Air direct from outside
High Level 10cm2 per kW* 5cm2 per kW
Low Level 20cm2 per kW* 10cm2 per kW
•Not permitted for installations exceeding 70kW
Note
Both air vents must communicate with the same room or
internal space or must both be on the same wall to
outside air.
Where compartment air vents are open to a room or internal
space, the room or internal space must itself have a permanent
air vent(s) as previously specified.
For multiple installations where the total heat input exceeds 70
kW reference must be made to BS 6644. The table on p7 should
be used to calculate requirements. Detailed recommendations
are given in BS 6644 Clause 19.
The following notes are intended to give general guidance.
Ventilation shall prevent the heater environment from exceeding
32°C.
The purpose provided space housing the heater(s) must have
permanent air vents communicating directly with the outside air,
at high and low level. Where communication with the outside air
is possible only by means of high level air vents, ducting down
to floor level for the lower vents should be used.
For an exposed building, air vents should be fitted preferable on
all four sides, but on at least two sides.
Air vents should have negligible resistance and must not be
sited in any position where they are likely to be easily blocked or
flooded or in any position adjacent to an extraction system which
is carrying flammable vapour or other contaminated air.
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3.5 Important
The supply of air to a space housing the heater(s) by
mechanical means should be:-
a) Mechanical inlet with natural extraction.
b) Mechanical inlet with mechanical extraction.
NB - Natural inlet with mechanical extraction must not
be used.
Where a mechanical inlet and mechanical extraction system
is used, the design extraction rate must not exceed one third
of the design inlet rate.
All mechanical ventilation systems must be fitted with
automatic gas shut off safety systems which cut off the
supply of gas to the heater(s) in the event of failure of either
the inlet or extract fans.
NB - The vapours given off by halogen based
compounds can, if drawn into the combustion air, cause
corrosion of the Storage Vessel and premature failure of
the thermocouple.
If water heaters are to be installed in locations where
halogens are likely to be present they should be isolated
from such compounds and ventilated from and to outside,
uncontaminated, atmosphere.
Some of the vulnerable areas are listed below:-
i) Hairdressing salons and adjoining rooms and basements.
ii) Establishments where dry cleaning solutions are used or
stored.
iii) De-greasing plants using hydrocarbon solvents.
iv) Premises where refrigerant gases are used or stored.
v) Environments with dust laden atmosphere
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3.6 Water Quality and Treatment
Where extreme conditions of water hardness exist, scale can
form in any water heating equipment, especially when the heater
is working under conditions of constant heavy demand and at
high temperatures.
Each water heater is fitted with a CorrexTM UP powered anode
as an alternative to the standard magnesium anodes. These
anodes do not need maintenance or replacement. The
potentiostat which regulates the current to the CorrexTM anode,
features an indicator light which shows green to indicate correct
function and red to indicate malfunction. These anodes are
available as an optional extra on all Andrews heaters.
In hard water areas, scale formation can occur in hot water
systems and hot water heaters. The higher the temperature and
volume of water used, the more problematic the scale build- up
can be. Water treatment is normally recommended when the
hardness reaches 100 - 150ppm (7 - 10 degrees Clark) and
above. This problem can be minimised by reducing the water
temperature in the heater and by fitting suitable water pre-
treatment equipment.
Note
When installing Andrews Water Heaters in hard water
areas we would recommend that a water treatment
specialist is consulted.
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3.7 Water Connections - General
3.8.1 Hydrojet System
The heater is fitted with the Hydrojet Total Performance System
incorporated in the cold inlet dip tube. The tube is designed to
increase turbulence and reduce sediment build up, reduce
thermal stacking and increase delivery.
The upper “jet ports”
direct the flow outward
to begin the dynamic
mixing action.
The lower “jet ports”
direct the flow inward
to increase the
turbulence. 3.8.2 Water Connections - Vented Systems
The water heater must be supplied from a cold water feed
cistern and the hot water supply pipe must be fitted with an open
vent pipe in accordance with BS 5546. Local regulations and by-
laws must be observed when installing the system but typical
water service layouts are shown in Figure 6 and Figure 8.
The cold water feed cistern must have an actual capacity
greater than the hourly recovery rate of the heater or heaters to
which it is fitted, the minimum actual capacity allowed for a feed
cistern is 227 litres.
The actual cistern capacity is the capacity to the normal water
line of the cistern. All cisterns used should be to the relevant
British Standard and the distance from the normal water line to
the top of the cistern should be as laid down by the water
authorities.
The cold water inlet and hot water outlet are identified on top of
the heater. Connect the cold water feed and hot water outlet to
these nipples with union adaptors for ease of servicing.
See
See Servicing Section 6.
Caution
Do not apply heat to these nipples if making capillary
soldered joints as they are fitted with plastic inserts. Make
the capillary joints to the pipes before connecting to the
heater. A drain cock is supplied with the heater and this
should be fitted to the appropriate boss as shown on the
drawing.
After installation of the water system open the main water supply
valve, flush the system and fill the heater. Open the hot taps to
allow air to escape from the system. When the system is free of
air, close the taps and check for leaks at the gas control
thermostat, drain cock and pipe connections at the top of the
heater.
Figure 5
Figure 6
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Figure 8; Open Vent
3.8.3 Water Connections - Unvented Systems
Unvented Systems should be fitted by an Approved Installer.
When used in an unvented system, the Andrews Water Heater
will supply hot water at a pressure of 3.5bar (50.8lbf/in2)
provided that this pressure is available at the mains feed. During
conditions of no-flow, system pressure may rise to a maximum
of 6bar (87lbf/in2) whilst the burner is operating. When testing
the system, it is recommended that a maximum test pressure of
8.62bar (125lbf/in2) is employed.
The heater can be used on unvented hot water storage systems,
with the addition of an Unvented Systems Kit, part number B171
available from Andrews Water Heaters.
All fittings and materials must be suitable for use with drinking
water and listed in the current Water Research Centre "Materials
and Fittings Directory".
Installation of unvented hot storage water systems must comply
with part G of Schedule 1 of the Current Building Regulations.
See
Figure 9 lists and illustrates the component parts of
the Unvented Systems Kit.
Figure 7 illustrates the general arrangement of
the components.
The Wall Mounting Kit is available as an optional extra.
Items D4/D6 must be fitted into the Temperature Relief
port (see Figure 8).
When assembling items D1 and D2 care must be taken to
ensure that the flow arrows marked on the components are
pointing in the direction of flow i.e. towards the water heater.
The cold water for services may be drawn from the 22mm
compression port on item D1(a). The water pressure at this point
will be similar to that available at the hot water outlet of the
water heater. If port (a) is not used it should be sealed with the
blanking plug supplied.
If higher flow rates are required for the cold water services a
suitable “tee” fitting should be included in the pipework upstream
of item D1.
The pipework fitted to both tundish outlets should be at least
28mm diameter and should be terminated at a suitable drain
(see Current Building Regulations Approved Document G3).
Figure 7
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3.8.4 Unvented Systems Kit
3.8.5 Unvented Systems Kit - Parts List
Ref. Part No. Description Qty
7703930 Unvented Systems Kit Complete 1
E1, E2 & E3 7705044
Combined Pressure Reducing Valve/Strainer & Check / Expansion Valve 1”
1
E4
7705037 Expansion Vessel (25 Litre)
1
E5 7705045
Temperature/Pressure Relief Valve
1
E6
7705047 Tundish from Expansion Valve and T/P Valve
1
E7 7705041 Hose Assembly 1
Figure 9
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3.9 Gas Connections
THE APPLIANCE MUST ONLY BE USED WITH NATURAL
GAS OR LPG.
The installation of the gas supply should conform to the
requirements of IM/16 published by British Gas p.l.c. or BS
6891. Jointing compound used must conform to BS 5292 pt 5.
Caution
Do not apply heat in close proximity to the gas control as
this will result in damage occurring to the control.
Fit the 1⁄2” m/f elbow into the gas control valve. Fit the 1⁄2” gas
supply cock immediately upstream of the gas control and elbow
and connect to the gas supply. Pressure test the gas installation
for soundness. If any doubt exists as to the size of gas supply
pipe, consult your local Gas Region.
It is recommended that a pressure test point is fitted on the input
next to the gas supply valve.
3.10 Electrical Supply
The method of connection to the mains electricity supply should
facilitate complete electrical isolation of the appliance,
preferably by use of an unswitched fused spur.
Alternatively, a fused double pole switch or fused spur box,
serving only the heater, may be used. A 3mm separation is
required between each pole.
The point of connection to the mains should be readily
accessible and adjacent to the appliance.
Wiring external to the water heater must be installed in
accordance with the I.E.E. Regulations for the wiring of buildings
and to any local regulations that may apply.
The Heater is designed to run off a permanent 220/240V 1 Ph
50 Hz supply and the fuse rating is 3 Amp.
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3.11 Wiring Diagram
Fig. 9
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4 Commissioning
Commissioning 4
4.1 HIflo EVO
4.1.1 To Light the Burner
Caution
Do not operate the water heater until the storage vessel is
completely filled with water, with water running from all
hot taps.
Open the main gas supply valve after all connections to the gas
control valve are complete, and test all connections with leak
spray.
1. Ensure electrical supply is on.
2. Ensure gas supply is on.
3. Change temperature format from °F to °C by following the
steps in Fig. 20 on page 28.
4. Set the desired temperature by following Fig. 12 to 18 on
pages 26 & 27.
5. Ensure time switch, if fitted, is in the on position.
6. If the burner does not light, an error code will be displayed
on the control display.
4.1.2 To Shut off the Burner
To shut off the burner isolate the electrical supply, then shut off
the gas service cock.
The water heater should only be turned OFF for long periods, eg
holidays or in an emergency. Otherwise the heater should be left
to operate under normal thermostat control.
Note
When using a time control ensure the heater is not turned
OFF before the final water draw off occurs. This will
ensure the water in the tank is left in a hot condition.
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